A rabies exposure incident in New Jersey provides another example of some common good and bad points that come up in these situations.
Fifteen people from four families, along with a veterinarian, are receiving post-exposure treatment after contact with a rabid kitten. In the all-too-familiar scenario, a kitten was found in a cat colony outside a workplace and taken home by a well-intentioned individual. A couple of weeks later, the kitten became sick, ultimately showing signs of neurological disease. It was euthanized at a local veterinary clinic, and subsequently identified as rabid.
A sibling of the rabid kitten that was adopted by a different family is under a strict six month quarantine. As opposed to most rabies exposure quarantines, the odds of this kitten being infected are reasonable high, so the little critter is certainly a concern.
The good points:
The kitten was taken to a vet.
- This may sound simplistic but it’s critical. If the kitten had died before being taken to the clinic, would testing have been performed? It’s hard to say but it’s much less likely. While people don’t tend to think about diagnostic testing after their pet has died, it’s important to consider what might have killed the animal and whether there are any risks to people that need to be evaluated.
Rabies testing was performed.
- Again, maybe this seems straightforward but this is a critical step. The veterinarian has to identify the potential for rabies (pretty easy here) and explain the need for testing to the owner (or alternatively, get public health personnel involved to seize the carcass and mandate testing… a much messier approach).
The bad points:
Lots of people were exposed to the rabid kitten - a total of 15 people from four families.
- That’s hard to prevent, in reality. Kittens attract attention. Whether all 15 individuals actually had contact worthy of calling them exposed to the virus itself isn’t clear. There’s no mention of anyone being bitten. However, given the sharp teeth and playful behaviour that can easily result in little bites (or saliva-contaminated scratches), it is much better to err on the side of calling someone exposed.
All 15 people went to an emergency room for treatment on a weekend.
- That’s a waste of resources and ER time. Rabies exposure is a medical urgency, but not an emergency. Rarely do you need to get treatment started immediately, especially if it wasn’t a large bite to the head or neck. They could have waited until regular hours and gone to their physician or public health. Often, there’s poor communication and lack of understanding regarding the time frame for post-exposure treatment, which can lead to this.
The veterinarian was exposed.
- That may have been unavoidable. However, a young, unvaccinated kitten adopted from a feral colony that has neurological disease is rabid until proven otherwise. Basic infection control practices can reduce the risk of rabies exposure. Maybe those were used and exposure still occurred; that’s possible, but it’s a reminder that prompt identification of rabies suspects and using good infection control practices is important.
It's that time of year again… time for the US annual rabies surveillance report in the Journal of the American Veterinary Medical Association (Dyer et al 2013).
- There were 6162 cases of rabies diagnosed in animals in 2012. (This is a 2.1% increase from 2011, but I don't put much stock into changes like that when the tested cases only represent a minority of the animals with rabies.)
- The vast majority (92%) of rabid animals were wildlife, with raccoons "winning" at 32% of all animals diagnosed. They were followed by bats (27%), skunks (25%), foxes (5.5%), cats (4.2%), cattle (1.9%) and dogs (1.4%)
- A variety of other animal species were also diagnosed as rabid, including bison, llamas, bobcats, deer, a cougar, a mink, groundhogs, opossums and beavers. That just shows how any mammal is at risk. I was surprised at the number of rabid groundhogs (42 in 10 states).
- While dogs accounted for only 1.4% of cases (84 animals), a disproportionate number were found in Puerto Rico (18), with relatively large numbers also in Texas (16), North Carolina (9), Georgia (7) and Oklahoma (7). Presumably this relates to a combination of lower vaccination rates and a higher level of endemic rabies in the wildlife population in these areas. It appears that none of the rabid dogs were properly vaccinated against rabies, although vaccination history was not known for many.
- Rabid cats were mainly found in areas where raccoon rabies was common. Pennsylvania had the most rabid cats (15.6%). Other commonly affected areas were Virginia, North Carolina, New Jersey and Georgia.
- The distribution of rabies virus types was pretty much as expected. Raccoon rabies virus predominated on the east coast. Skunk rabies covered the central US, overlapping with fox rabies in the southern regions. Fox rabies was also dominant in the Nevada and Arizona area, while skunk rabies predominated in central to northern California. Fox rabies dominated in Alaska and the mongoose rabies virus strain was found in (not surprisingly) Puerto Rico.
Some Canadian data were also reported:
- There were 142 confirmed rabies cases in animals, 84% of which were wildlife.
- There were 18 rabid cats and dogs, 4 livestock and one person. The person was infected with rabies while abroad, in Haiti.
- No rabid raccoons were found - something that has been the case since 2008.
And in Mexico…
- There were 12 cases of rabies in dogs, and those involved the canine rabies virus variant which is not present in Canada or the US.
Take home messages:
- Rabies... still here (and not going away any time soon).
- Vaccinate your animals.
- Stay away from wildlife.
Image: Distribution of major rabies virus variants among mesocarnivore reservoirs in the United States and Puerto Rico, 2008 to 2012. (click for source: Dyer et al. J Am Vet Med Assoc 2013)
I've had the occasional debate with people about the public health risks of rabies in horses.
On one hand...
- Rabies is rare in horses.
- I've never seen a report of rabies transmission from a horse to a person.
On the other hand...
- Rabid horses have attacked (and killed people).
- It doesn't matter whether the horse gave you rabies or stomped on you. Dead is dead.
A Carroll County, Georgia horse owner learned the risk of rabid horses the hard way, but fortunately doesn't appear to have been seriously injured. .
One day, the owner was bitten while getting the horse out of the pasture.
The next day, the horse attacked him....and according to the owner, tried to kill him. That night, the horse was in the pasture chewing on its leg and periodically nosing the electric fence.
While rabies is rare, these are some of the hallmarks...aggression and strange behavior. The horse was euthanized and tested positive for rabies. Presumably, the owner is undergoing rabies post-exposure prophylaxis.
Rabies is nothing to play around with. It's very rare in horses but endemic in wildlife so there's always a chance for exposure in most regions. Rabies vaccination is a cheap and highly effective way to reduce the risk.
Alberta Health Services Medical Officer Dr. David Strong has urged the public to take precautions after a Calgary-area puppy was diagnosed with rabies. The five-month-old puppy came from Nunavut and had not been vaccinated against rabies. All those with whom the puppy had contact have been assessed and it doesn't sound like anyone required post-exposure treatment.
Since rabies is endemic in wildlife in the region, finding rabies in a puppy (especially when the puppy was presumably exposed elsewhere) doesn't mean that there's any greater risk to the public than there was before the case was identified. The imminent concern is the presumably limited number of people and animals with which the puppy had contact while it may have been infectious, but it's always useful to remind people about rabies and precautions they should take to prevent rabies exposure. In the infectious disease world, we often have to take advantage of high profile incidents to drive home some basic principles that we'd like people to pay attention to all the time.
Key rabies prevention points include:
- Avoid contact with wildlife.
- Keep your pets away from wildlife.
- Ensure your pets are up-to-date with their rabies vaccination.
- Make sure any bites from wild or domestic mammals are reported to public health so that it can be determined whether rabies post-exposure treatment is required.
Pretty basic. Common sense goes a long way with infectious disease prevention.
The word "ironic” gets used a lot, often incorrectly.
Alanis Morrissette’s hit song “Ironic” is a great example of this since she (ironically?) describes situations that aren’t really ironic, they just suck (i.e. winning the lottery and dying the next day isn’t ironic, it’s just bad luck).
Anyway, irony doesn’t have much to do with the topic at hand, apart from picking on the title of a news report “In ironic twist, dogs of local rabies survivor Jeanna Giese are exposed to bat that tested positive for the disease.” It’s not really ironic, but it’s an interesting story.
If anyone knows about the implications of rabies, it’s Jeanna Giese. She will forever be remembered in the medical world as the first person to be successfully treated after developing rabies. When she was 15, she picked up a (rabid) bat and was bitten. Not knowing any better, the family cleaned the bite wound but did not take her to a doctor. A little over a month later, she developed neurological disease. At that point in time, rabies was still called "invariably fatal," but she was treated with an experimental protocol that involved, among other things, putting her in a coma and treating her with antiviral drugs. Remarkably, she survived. More remarkably, she didn’t just survive, she was able to go back to school, learn to drive and function normally. (As a result of her miraculous recovery, rabies is now termed "almost invariably fatal.")
Jeanna has become an advocate for both animals and rabies awareness, using her personal experience to get her message across. Well, now she has one more personal experience to add to her repertoire.
Recently, she found a bat in the enclosure that houses two of her dogs. The bat was dead and covered in dog bite marks. Presumably in no small part because of her heightened awareness of rabies, she submitted the bat for rabies testing - and it was positive. So, her dogs were considered exposed. “How many people in the entire world can honestly say that a rabid bat has affected their lives twice in nine years?” she asks. Fortunately, her dogs were vaccinated against rabies and therefore they only have a relatively short observation period at home to go through, as opposed to a strict six month quarantine or euthanasia.
Awareness of rabies is the key, whether you’re trying prevent exposure of yourself, your family or pets. It’s also an area that needs improvement. As Ms. Giese said, "It's not surprising people know little about rabies... I didn't. You can't walk into a counselor's office and just pick up a pamphlet about rabies. I'm teaching kids that it's out there and what to do. Had I known what I know now, I would have made a different decision (about picking up the bat in 2004)."
Ironic? No, but a good story nonetheless.
ProMed-mail usually posts a monthly recap of rabies cases in the US. The most recent one (like most of them) doesn't have anything too astounding, but it provides some good reminders.
Skunk attacks baby
A five-month-old baby that was outside in a car seat was bitten in the face several times by a skunk. The skunk was killed and tested positive for rabies. This is a high risk situation because it involves a young child and bites to the face. Because of that, the incubation period would potentially be very short so prompt treatment of the baby would be needed (and presumably post-exposure treatment was started right away).
Rabid family dog attacks
Five people were bitten by their pet dog, which was subsequently identified as being rabid. This should be a reminder that rabies exposure is still a concern with pets, that pets should be vaccinated, and that rabies exposure must be considered after any bite.
Fox + bite + electric hedge clippers = ...
A Virginia man was bitten by a fox, and he then killed the fox with hedge clippers (probably not a pretty sight). The bite did not break the skin (although the man did pass out afterward... not sure whether that was from fear of the bite or the aftermath). Anyway, the fox is only being reported as "presumed" rabid. Given the time frame of the encounter and the press release, I would have thought they'd know the rabies status of the animal, if it was tested. In the absence of knowing that the fox was not rabid, they'd have to assume that it was and take appropriate measures. Since the bite didn't break the skin, the bite shouldn't be considered rabies exposure; however, depending on how gory the subsequent fox-clipping was, there might have been exposure to infectious tissues by other means, and post-exposure treatment might have been indicated anyway.
Calf bites, animal health personnel screw up
Rhode Island health officials are trying to track down anyone that might have been exposed to a calf that lived next door to a popular ice cream shop. The calf bit someone and was quarantined. However, it died the next day and in a pretty major screw-up, local animal health officials didn't notify the state until 3 days later. By that time, the calf's body was too decomposed to be tested for rabies. So, it must be assumed that the calf was rabid.
A few take home messages:
- Rabies is still around... think about it.
- Vaccinate your pets.
- Avoid contact with wildlife, and if wildlife is behaving abnormally (e.g. attacking), rabies must considered.
- Make sure all bites from mammals are reported so that the need (if any) for rabies post-exposure treatment can be determined.
- Hedge clippers are not the best euthanasia tools.
As if horse owners and veterinarians in Queensland need another infectious disease challenge.....
Recently, a horse in southwest Queensland was diagnosed with Australian bat lyssavirus infection. This virus, which is similar to rabies, is present in some bats in Australia. It can be transmitted to people from bats, causing fatal disease, but human infections are very rare. Even though it's rare, it warrants attention because the disease is so severe.
Finding an infected horse is surprising in some ways, because the virus has never been detected in this species before. However, a virus that's present in bats can certainly find its way into a horse, and we already knew that a closely related virus (rabies) can infect horses. So, maybe it's not that surprising afterall.
In this case, the horse was suspected of being infected with Hendra virus initially. While Australian bat lyssavirus can kill people, this diagnosis was actually much better than Hendra virus infection, because horse-human transmission of Hendra is a major concern. Hendra virus infections have high fatality rates and, perhaps most importantly, there are no effective preventative measures that can be taken after Hendra virus exposure. Since Australian bat lyssavirus is so closely related to rabies virus, rabies post-exposure treatment can be used in this case (and is probably effective).
It's unclear whether an infected horse poses much risk to people. The very small number of human Australian bat lyssavirus cases have occured in people who were bitten or scratched by bats. Since this is the first equine case, it's not known if affected horses shed large amounts of (or any) virus. People who had contact with the horse were identified and offered post-exposure treatment. It's reasonable to consider this situation like rabies exposure in the absence of more evidence, and treat people who were bitten or otherwise may have gotten virus-contaminated saliva into their tissues via broken skin or mucous membranes.
Is this the start of yet another new problem?
Most likely, this is just an example of the rare scenario of a virus infecting an atypical host, not the start of a new, common problem. However, it's worthy of attention in case the virus has changed or there is now a specific virus type that can more easily infect horses (both very unlikely). This case also shows the importance of thorough diagnostic testing, particularly when an animal has severe disease.
If you don't look, you don't find.
If you don't find, you can't act.
Business Mirror, a Philippine news website, had a recent article entitled "Rabies: deadlier than ever". That's a bit like saying Decapitation: now an even worse idea. Rabies isn't 'deadlier than ever,' since it's hard to get deadlier when the disease is already almost invariably fatal.
Anyway, beyond quibbling about the title, there are some interesting parts to the tragic story.
The article describes the death of a young boy. He was attacked by a dog while playing in his front yard in the Philippines. After the attack, he was taken to the hospital where, while he treated for some large scratches, he was not treated for rabies exposure because there were no bites.
This isn't too surprising, since it's an area in which there are some education gaps and misconceptions. The main risk for rabies transmission from dogs is from bites, since the virus is present in high levels in saliva, and bites directly inoculate saliva into the body. Rabies contaminated saliva deposited on intact skin isn't a risk. Rabies virus shouldn't be hanging out on a dogs paws, so it's easy to see how the transmission risk from scratches might be overlooked. However, during an attack, saliva contamination of the skin and a scratch that breaks the skin can both occur, thereby inoculating rabies virus into the body just like a bite.
Presumably that's what happened here, because 2 months after the attack, the boy developed rabies. It started with severe itchiness over the site of the scratch, and he was dead two days later.
We can't play around with rabies. If there's potential that an animal interaction led to rabies exposure:
- The animal must be identified and either euthanized so its brain can be tested, or (if a dog or cat) quarantined for 10 days to ensure that it does not exhibit any signs of rabies.
- If the animal can't be identified and quarantined or tested (or if it's positive for rabies), proper post-exposure treatment is required.
More information about rabies can be found on the Worms & Germs Resources - Pets page.
ProMed Mail's monthly US rabies update often contains some interesting cases, and the last one is no exception.
A llama in Georgia became aggressive, started biting itself and was spitting at one of its caretakers. A spitting llama certainly doesn't mean rabies (I have dodged enough llama spitballs to know that) but any sudden change in behaviour, especially with aggression, should raise some major red flags. Here, the llama was diagnosed as rabid and the person that was spat on is receiving post-exposure treatment.
A bobcat attacked a man and boy in Massachusetts, and not surprisingly, was diagnosed with rabies. In this case, the bobcat pounced on the man, bit his face, clawed his back and held him in something akin to a bear hug, before moving on to the man's nephew. Wild animals don't typically attack except under extenuating circumstances (e.g. being cornered, protecting offspring), so this type of event should be considered a rabies exposure until proven otherwise. The man shot the bobcat and it was confirmed as rabid.
In an all-too-common scenario, a family that took in a stray kitten ended up needing post-exposure treatment because the kitten was rabid. They found the sick kitten and tried to nurse it back to health, but it died the next day. Fortunately, animal control arranged for rabies testing, something that could have easily been overlooked if no one thought about rabies and just assumed the kitten was sick for some other reason. Two dogs in the household were also considered exposed, but fortunately had been properly vaccinated, so typical recommendations would be for a 45-day observation period versus 6 months strict quarantine or immediate euthanasia had they not been vaccinated.
In a similar scenario, two women are undergoing post-exposure treatment after being bitten by a stray kitten they were trying to catch. After they caught the kitten, they took it to a local Humane Society, where it was euthanized because of the bite. This ended up being an efficient approach, but more often there would be a 10 day observation period of an animal that had bitten someone, to see if it developed signs of rabies. If signs occurred the animal would be euthanized and tested for rabies, but if not then (theoretically) the animal would not have been shedding rabies virus at the time the bite occurred. Immediate euthanasia after a bite is not the typical recommendation, so I wonder whether the kitten was already showing some signs of disease. Otherwise, it wasn't a textbook approach to bite management but it ultimately resulted in the right outcome.
These cases have a few recurring themes:
- Changes in animal behaviour should lead to consideration of rabies.
- Be wary of stray animals. It's best to stay away from them. If you end up taking in a stray, if it gets sick and dies, ensure that it is tested for rabies.
- Vaccinate your pets because you never know when you'll encounter rabies.
Public health personnel in Chapin, Connecticut (USA) are trying to find a woman bitten by a rabid cat. The woman was driving down South Brear Hill Road when she came across a cat. She picked the cat up from the road and told someone else who was there that the cat bit her. She then drove away, and the cat was subsequently identified as being rabid. Now a search is underway to find the woman so she can be given post-exposure treatment.
This is clearly a high risk situation. As opposed to other public health alerts that try to find people who were in contact with a rabid animal on the off chance that they were bitten or otherwise exposed to the virus, this person was bitten and that creates a very high risk of rabies transmission.
The outcome is simple.
- If she gets rabies, she will almost certainly die.
- If she was exposed but gets post-exposure treatment soon (and completes the recommended course), she will almost certainly live.
It's easy to see how this could happen. The woman probably found the cat looking injured or lost on the road, and wanted to help. However, that action, and failure to recognize the risk associated with the bite, have put her life at risk.
A few general rabies reminders:
- Avoid contact with wildlife or any animals you don't know, especially if they seem sick or otherwise abnormal.
- If you are bitten, make sure the potential for rabies exposure is considered. The animal needs to be observed to see if it is rabid, or it needs to be tested. If the animal can't be monitored or tested, you can't rule out rabies and getting post-exposure treatment is the safest course of action.
More information about rabies can be found on the Worms & Germs Resources - Pets page.
a) there are more rabid beavers these days,
b) rabid beavers have always been around in these numbers but they have recently acquired a taste for human flesh, or
c) it's just a fluke,
The latest incident involved a beaver in West Springfield, Virginia that chased after some kids at a nature centre. The kids had been swimming and saw a beaver swimming towards the dock. It's not that unusual to see beaver's swimming around in some areas, but like most wildlife, they typically stay away from people. Not this one though. It "leaped out of the water onto the dock, acting aggressively and chasing the children." Police shot the animal and testing confirmed it was rabid. Presumably, no one required post-exposure treatment since there were no bites.
While rabid beavers are rare, this and earlier incidents involving attacks by rabid beavers, otters and other critters highlight some basic principles regarding rabies safety:
- Stay away from wildlife.
- Mammalian wildlife that are acting abnormally, including displaying no fear of humans, should be considered rabid until proven otherwise.
- Any bite by a wild mammal should be considered a potential rabies exposure. The animal should be tested whenever possible and if it can't be shown that the animal wasn't rabid, it must be assumed that there was rabies exposure.
Common sense goes a long way toward avoiding rabies exposure, but sometimes it's not avoidable. Knowing what to do in the event of a bite from a wild and potentially rabid animal is important. The key is involving physicians and public health personnel who understand rabies exposure risks, so that a proper risk assessment can be done and treatment can be started promptly if it's indicated.
Image: A North American Beaver (Castor canadensis), by Laszlo Ilyes (click image for source)
The annual US rabies surveillance report has been published in the latest edition of the Journal of the American Veterinary Medical Association (Blanton et al 2012). There's not really anything earth-shattering in it, but it's a good overview of the rabies diagnoses in the US from 2011. As always, it only provides a peek into rabies in wildlife (since only a small percentage of wildlife with rabies get diagnosed and reported) but numbers and trends in domestic animals, along with general wildlife data, provide useful information about the state of this virus in the US. Among the highlights:
- Rabies was diagnosed is 6031 animals and 6 people, from 49 states and Puerto Rico (Hawaii remains rabies-free). This is a 2% drop in animal cases from 2010, but I don't put much stock in that because the numbers are weighted towards wlidlife cases, and it's hard to have confidence in year-to-year numbers of rabid wild animals (because it's so dependent on what actually gets tested).
- The main wildlife species that are involved in maintaining the rabies virus in the US (reservoir species) continue to be raccoons, bats, skunks and foxes on the mainland, and mongooses in Puerto Rico. The relative importance of these species varies between regions.
- Raccoons were the most commonly affected species, accounting for 33% of all rabid animals reported. Other leading species were skunks (27%), bats (23%) and foxes (7%). Less common species included coyotes, bobcats, javelinas, deer, otters, mongooses, wolf hybrids, groundhogs and beavers.
- Cats were the leading domestic animal, with 303 diagnosed cases. Dogs came in next with 70, followed by cattle (65), horses (44), and goats and sheep (12). There were also single cases in a domestic bison and an alpaca.
- The six human cases represent the highest annual number of cases since 1994, if you exclude 2004 where four cases were associated with transplantation of organs from a single infected person. In a review of the 24 domestically-acquired human cases from 2002-2011, 88% were linked to bats.
- Three of the six 2011 human cases were acquired outside of the US; one each from Haiti, Afghanistan and Brazil - and all from dogs.
- Two of the three domestically-acquired cases were associated with bat contact. The source of the remaining case, an eight-year-old girl, is unknown, but contact with cats from a feral colony near the girl's school is a possibility.
- 5/6 people with rabies died. That's actually an impressive survival rate, since any survival is still a very noteworthy event when it comes to rabies. The survivor was the eight-year-old girl, and she apparently has suffered no longterm cognitive impairment.
Interestingly, we get a good synopsis of Canadian rabies data in this report too:
- 115 rabid animals were identified, with 92% being wild animals.
- There were three rabid livestock (two of which were horses) and six dogs and cats.
- No rabid raccoons were identified, continuing a trend started in 2009.
And regarding rabies in Mexico:
- 148 rabid animals were identified, mainly cattle (82%).
- Rabies was diagnosed in 20 dogs, with evidence that the canine rabies virus variant (which has been eliminated from Canada and the US) is circulating in some regions.
- There were three humans cases: two acquired from vampire bats and one from a skunk.
Rabies is most commonly reported in dogs, skunks, raccoons, bats and a few other species. However, any mammal is susceptible, and sometimes unusual cases are identified.
1. In a serious take on Monty Python's "killer rabbit," a rabid bunny has caused a lot of problems in Chom Thong, Thailand.
The pet rabbit, Poko, had been purchased last year and starting biting the feet of people in the family on June 10. The rabbit was eventually put in a kennel and died July 28. The other rabbit in the house died the next day (no word on why). The time frame is a bit strange, since if the rabbit was biting because of rabies, it should have died a lot quicker. Once an animal is showing signs of rabies, death occurs quite quickly (usually within 10 days), not over a period of 7 or 8 weeks. So, most likely the rabbit wasn't biting because of rabies, at least at the start.
In response to the diagnosis, authorities have launched an investigation and 120 health officials are fanning out in the area to look for other rabid animals, since where there is one, the are others. Dogs and cats within 5 km of the rabbit's home are being vaccinated against rabies. Family members are being given post-exposure prophylaxis. The father has expressed concern that the treatment was too late since they were bitten several days before, but it's not really much of a risk. Rabies typically has a long incubation period, especially with bites to lower extremities, and starting treatment a few days (or even weeks, in some situations) after exposure can still be effective (albeit the sooner the better). The key is for treatment to be started before any signs of rabies develop - after that happens there's very little that can be done.
The source of rabies isn't clear and I haven't seen any speculation. If the rabbit was caged, then there aren't too many possible sources, with bats probably being the most likely.
2. Swimmers beware... it's not just rabid otters you need to worry about.
A man swimming in eastern Pennsylvania was bitten by a beaver that was subsequently identified as rabid. The beaver apparently attacked a canoeist earlier that day, before encountering the swimmer, a Boy Scout leader. The man suffered 15 lacerations from the attack, and the beaver remained firmly attached to the man's arm as he was helped to shore. The stubborn critter wouldn't let go until the resourceful (and brave) Scouts got it off by hitting it with "anything they could find around them, sticks, rocks..." The beaver was killed and confirmed as rabid.
It's another reminder that any bite from a mammal should be considered a possible rabies exposure. It's also a reminder to avoid contact with wildlife, although that can be easier said than done when a rabid animal is involved.
The old saying is "when you hear hoof-steps, think horses, not zebras." In a medical context, it means common things occur commonly, so don't start off thinking about wild and bizarre conditions before you've ruled out the usual suspects. Along that line, when I hear "rabies," I think "bats, raccoons, dogs, cats, foxes..." I don't think about... zebras.
Considering there aren't that many zebras in Ontario, and even in places where there are zebras, most people don't have a lot of contact with them, it makes sense that zebras don't typically make the rabies suspect list. But that doesn't mean zebras can't get rabies.
A Letter in Emerging Infectious Diseases (Lankau et al, 2012) describes one such unusual scenario. In January of 2011, an orphaned zebra foal was taken in by a safari lodge (that's probably not too unusual of an occurrence), and not surprisingly, tourists were allowed to handle and feed the foal. Unfortunately, the foal was bitten by a dog at the end of July. The dog was suspected of being rabid but it doesn't seem like any changes were made to how the baby zebra was handed. Unfortunately, the foal died at the end of August and rabies was confirmed. Lodge staff tried to contact people who had visited during the July-August time period, mainly through emails to travel-booking agents who (it was hoped) forwarded the information to travelers.
Several US travelers contacted CDC after getting the email and their risk of rabies exposure was investigated.
- CDC obtained names of 243 travelers who were at the lodge, 136 of whom were from the US.
- They worked with the assumption that the outside window for rabies virus shedding by the zebra was a 14 day period leading up to its death. Seventy-seven (57%) of the US visitors had been there during that period.
- Twenty-eight of those visitors had already started post-exposure treatment for rabies. None of those individuals had high-risk exposures, 2 had moderate-risk exposure while the rest had low or no-risk exposures, so treatment would not have been recommended for most of them. That's probably because the information went from the lodge to travel agents to travelers, and then to the peoples' general physicians (who are generally less well versed in rabies exposure issues) rather than through public health.
- The cost of rabies post-exposure treatment is at least $4000/person in the US (although I know of cases where the cost was much higher), so at least $100 000 was wasted, in addition to stress and other factors.
Some take home messages
- People need to think about animal contacts when on vacation. Travelers that go to rabies-endemic areas need to pay particular attention to avoid high-risk contact with animals.
- Facilities that allow animal contact need to protect the public. Rabies vaccination of this foal might have prevented its infection and the subsequent human exposures.
- If an animal has been attacked by a rabid animal, don't let people come into contact with it!
- Rabies exposure is a medical urgency, not an emergency. There's time to make sure things get done right, and public health personnel should be involved in discussions of exposure and treatment.
I've had a run on questions about survival of rabies virus outside the body. The topic comes up periodically with respect to touching roadkill or veterinary clinic personnel working with animals that have been attacked by an unknown animal. The case of three people who developed rabies after taking care of a sheep that had been attacked by a rabid animal, probably through contact with saliva from the rabid animal on the sheep's coat coming into contact with broken skin on their hands, shows the potential risk. An important part of assessing the risk is understanding how long the virus lives outside the body.
Some viruses are very hardy and can live for weeks or even years outside the body. Parvovirus and norovirus are classic examples of this type. Some viruses, like HIV, die very quickly in the environment. Part of this relates to whether they are "enveloped" or "non-enveloped" viruses. Enveloped viruses have a coating that is susceptible to damage from environmental effects, disinfectants and other challenges. Damaging this coating kills the virus. Non-enveloped viruses don't have that susceptible coating and that is in part why they are so much hardier.
Fortunately, rabies is an enveloped virus, and it doesn't like being outside of a mammal's body. Data on rabies virus survival are pretty limited, since it's not an easy thing to assess. To look at rabies virus survival, you have to grow the virus, expose it to different environmental conditions, then see if it's still able to infect a mammal or a tissue culture. We can do this easily with bacteria, but growing viruses is more work, especially a dangerous virus such as rabies virus.
I can only find one study that has looked at rabies virus survival (and I can only read the abstract since the rest of the paper is in Czech). The study (Matouch et al, Vet Med (Praha) 1987) involved testing of rabies virus from the salivary gland of a naturally infected fox. They exposed the virus to different conditions and used two methods to look at the infectivity of the virus.
- When the virus was spread in a thin layer onto surfaces like glass, metal or leaves, the longest survival was 144 hours at 5 degrees C (that's ~ 41F).
- At 20C (68F), the virus was infective for 24h on glass and leaves and 48h on metal.
- At 30C (86F), the virus didn't last long, being inactivated within 1.5h with exposure to sunlight and 20h without sunlight.
So, rabies virus can survive for a while outside the body. Temperature, humidity, sunlight exposure and surface type all probably play important roles, but in any particular situation you can never make a very accurate prediction of the virus's survival beyond "it will survive for a while, but not very long."
From a practical standpoint, it just reinforces some common themes:
- People should avoid contact with dead or injured animals.
- Veterinary personnel or pet owners dealing with a pet that has been attacked by another animal should wear gloves, wash their hands and take particular care if they have damaged skin.
- People who are at higher than normal risk of being exposed to potentially rabies-contaminated surfaces should be vaccinated against rabies.
Image: Schematic diagram of a rabies virus showing the outer viral envelope (source: CDC Public Health Image Library)
Travel always carries a risk of infectious diseases. More people are paying attention to their health and going to travel clinics to find out about these risks and what preventive measures they can take. They still constitute only a minority of travelers, but it’s an improvement. There aren’t travel clinics for pets, so travelers thinking about pets and infectious diseases need to rely on sources like their regular veterinarians and government websites.
Unfortunately, that doesn’t always result in good information, as shown in a study recently published in Zoonoses and Public Health (Davidson et al 2012). For the study, the authors called veterinary clinics in eight European countries (Austria, Belgium, Finland, France, Germany, Sweden, Switzerland and the UK) and asked them about taking a dog to Norway. They also called clinics in Norway and asked about bringing a dog to the country from an unspecified location in Europe. Calling was done not as a research survey but by a person pretending to be a pet owner.
The study focused on two main pathogens, Echinococcus multilocularis (a tapeworm that is present in some parts of Europe but not others, and one that is both an animal and public health concern) and rabies. Only 9% of clinics provided accurate information about these two problems. Some clinics (58%) referred people to government sites that have good information, but unfortunately 13% of clinics referred people to websites or government agencies that provided incorrect or incomplete information. When information from websites is included, people received correct advice 62% of the time. Not bad but not great.
Among the bad advice that was given (or important information that was not given):
- Failure to tell people about the requirement for tapeworm treatment after arrival.
- Incorrect tapeworm treatment information.
- No mention of rabies titre testing.
- False information that pets traveling to Norway don’t require tapeworm treatment.
This shouldn’t be taken as indicating that veterinary clinics aren’t competent. Travel medicine certainly isn’t something I was taught in vet school. Most veterinarians (understandably) don’t spend much time reading about problems that only occur in other geographic regions, since there’s enough other new information on which they must stay current. So, they may not have answers at the tip of their tongues when asked a question. Trying to get good information by random phone calls or as an aside during a veterinary appointment might not be the best approach. However, since we have a surprisingly mobile pet population, with pets traveling with owners to many different regions, it’s an important area for veterinarians to think about, from two standpoints:
1) Counseling people who are traveling: As was the focus here, it’s important for people to know about disease risks and regulatory requirements for places to which they travel. Specific preventive measures (e.g. vaccination, deworming) that are not needed at home may be indicated when traveling.
2) Diagnosing disease in returning animals: It’s easy to miss travel-associated diseases, and that can lead to bad outcomes. If veterinarians don’t ask whether a pet has traveled, they won’t realize that there might be some other diseases to consider. If they don’t know about disease concerns in other regions or (perhaps more importantly) don’t have ready access to good information about disease risks in other regions (e.g. accurate websites), they might not consider important diseases even if they ask about travel history.
This study highlights a few of the current gaps in the system, involving background knowledge, client communications and variable accuracy of electronic sources. People who are traveling with pets (or acquiring pets from abroad) should have a thorough discussion with their veterinarian (not just a casual call to the veterinary clinic, during which information may come from or through lay staff) about the situation, and they need to do their own homework. It's probably best to make sure the clinic knows that there will be travel questions in advance, so mentioning it at the time of booking the appointment might help.
As the authors of this research state “An accessible, centralized, easy to use website, that is updated by a central regulating agency and applies to all countries, would allow veterinarians to refer pet owners to one site for further information regardless of which country they are travelling from and going to.”
That's the ideal situation. Given the minimal attention that governments pay to pet animals, it's probably going to have to be an government-independent, collaborative venture. We've had some discussions about this in the past and it would be great to do, but the logistics are a bit daunting. Maybe it's time to resurrect those discussions.
This time of year, it's very common around here to see young raccoons wandering about. It's also still pretty common to hear about people keeping a litter of baby raccoons in their house. I can understand the appeal - they're cute and entertaining. However, in addition to being illegal in many regions, handling young raccoons also poses a risk of exposure to a variety of infectious diseases.
Chief among the infectious disease risks of handling young raccoons is rabies, as a Walker County, Alabama, family found out. Two baby racoons were found in someone's attic, and another two littermates were found a little while later. The person who found them gave two each to two separate people. As is often the case, they were handled by many different individuals before one of the raccoon kits was found to be rabid. Now more than 20 people are facing post-exposure treatment. It's one of the larger reported exposures from a single rabid raccoon, but it's far from unprecedented.
Beyond the obvious public health concern, this situation demonstrates another possible issue. Rabies is sporadically distributed in some regions, and moving wild animals around leads to the potential for dissemination of rabies, as well as other infectious diseases. Raccoon rabies is present in the area where the baby raccoons were found, but has not been found in Walker County, even though it's not far away. If the rabid raccoon had escaped (or was released), it could have potentially spread rabies into an area where it's currently not well established, thereby increasing the risk of exposure to everyone (animals and people) in the county.
As mentioned above, it's also illegal to harbour wildlife in many regions if you are not a licensed rehabilitation facility. While getting fined seems to be uncommon, four people in this incident have been charged with unlawful possession of a protected animal. Just one more reason not to do this.
While baby raccoons may have some appeal, as Alabama's state veterinarian Dee Jones says, "...people just need to stay away from them."
Case 1: A veterinary technician was infected through contact of broken skin with saliva. The man had scratched skin on his hand, which he put in the mouth of a rabid cow during a procedure. This situation brings to mind several important points:
- All veterinary personnel in rabies endemic areas should be vaccinated against rabies. I don't know about rabies vaccine supply issues in Iran, and that might be a limiting factor, but there are still too many unprotected veterinary personnel in most countries.
- This person seemed to have known that rabies was suspected in the cow, but apparently didn't consider this kind of contact to constitute exposure, so he didn't seek treatment. Once he started to get sick, he actually suspected rabies well before his physicians, so he obviously was well informed about the disease.
- There is a need to consider rabies when evaluating any animal, to use proper barriers (e.g. gloves) when handling rabies suspects, to test for rabies when there is any chance an animal has died of the disease, and to get post-exposure treatment if there has been a potential exposure to the virus. These steps aren't always straightforward, especially since signs of rabies in cattle can be quite variable.
Cases 2-4: There were three members of the same family tending a herd of sheep and one of the sheep was attacked by a rabid wolf. The three individuals were believed to have been exposed while tending to the sheep, since their hands were scratched in the process and it was thought that rabies virus-laden saliva still on the sheep's wounds got into those scratches.
- This one surprises me. It's not a route of rabies exposure we typically consider, since rabies virus is quite labile (i.e. rabies virus does not survive long once it's exposed to the environment, even on the outside surface of a wound). I guess it makes sense if the three individuals were scratched and exposed to saliva right after the attack. I don't think this indicates broad risk to people who take care of animals that have been attacked, but it's something to think about when dealing with an animal that has just been attacked. It's another reason that we should be wearing gloves when handing open wounds (typically, gloves are recommended to protect the individual with the wound, but it goes both ways) and take care to perform proper hand hygiene. However, both of these are hard to do while tending a flock of sheep in rural Iran.
Case 5-6: These individuals were infected through corneal transplants from the same donor. The donor was reported to have died from "food poisoning," although undiagnosed rabies must have been the true cause (unless you have the very unlikely situation that the person was infected but coincidentally died of food poisoning just before signs of rabies developed).
- Corneal transplants have been associated with transmission of various diseases, and transplant-associated infections of many kinds have caused many deaths. That's why there are strict protocols for screening donors, both in terms of what they died of and what testing is required. I'm surprised they'd use tissues from someone who died with an inexact diagnosis such as "food poisoning," especially since that can have an infectious cause.
Overall, these non-bite associated cases account for a small minority of human rabies cases that occur every year, but unusual routes of exposure need to be considered in any case.
Israel's Health Ministry is recommending rabies vaccination for people traveling to India.This seems to be mainly in response to the recent high-profile case of an English woman who died of rabies acquired from a dog in India. While it was high-profile, that certainly wasn't the only travel-associated rabies infection in the past year. Rabies exposure is a serious concern for people who might encounter dogs (intentionally or accidentally) while traveling in countries with endemic canine rabies. The news report states that rabies vaccine is available at clinics in Israel for would-be travelers, however it doesn't say whether the cost of vaccination is covered by the government. Human rabies vaccination is quite expensive, which may be a limiting factor when it comes to convincing travelers to get vaccinated, unless the government foots some or all of the cost.
Raising awareness of the problem with rabies in some developing countries is good. Most people don't really think about travel-associated disease (beyond the ubiquitous diarrhea that comes with travel to some areas), particularly something like rabies. In addition to focusing on vaccination, however, it would be even better to see a broader initiative to remind people to avoid contact with stray dogs (and other animals) and to make sure they get proper medical care after potential rabies exposure. Also, while India is certainly a hotbed of canine rabies, it's important to remember that there are many other countries where dog rabies is a major problem, and similar measures need to be taken for travel to these places too.
A surprisingly large number of people get sick and die every year from diseases acquired during travel. Travelers need to be aware of disease risks in areas they visit, know what preventive measures they should take and how to get proper medical care in any region they visit. While thinking about this might put a damper on vacation planning, it's worth the effort. When it comes to rabies, unless you know that a region is officially (and truly) rabies-free, assume that any encounter with a wild mammal, especially a stray dog, could be a source of rabies exposure. You don't want to travel in a bubble and stick to sterile locales, but you also don't want to come down with a fatal disease when some basic precautions could have prevented it.
While rabies is classically transmitted from animals to people by bites, any situation that allows saliva from an infected animal to get past the body's protective skin barrier can result in infection. Graeme Anderson, a 29-year-old South African canoeist, recently died after contracting rabies from a sick dog for which he was caring. There was no history of a bite, but the dog had licked damaged skin on the man's hands, allowing the virus to enter the body.
Any contact with animals showing signs consistent with rabies needs to be investigated. Licks over damaged skin (or mucous membranes like the mouth) are classified by the World Health Organization as having the same level ("severe") risk of rabies exposure as bites, and post-exposure prophylaxis is indicated. Bites are the main source of rabies transmission, but not the only source, the fact of which situations like this remind us.
A 50-year-old UK woman, the first of two recent travel-associated rabies cases in the UK, has unfortunately but not surprisingly succumbed to the infection.
The woman was bitten by a puppy while traveling in India. Given the widespread nature of rabies in dogs in India and the large number of human rabies deaths associated with canine rabies there, this was a high-risk exposure. I still haven't seen any information about whether she sought medical care in India or not. Too often, people don't bother to go to a doctor after being bitten, especially if the bite appears minor - but even a minor bite can transmit rabies. Furthermore, people don't always get the care they need, since rabies treatment is astoundingly not always offered after dog bites in India, and rabies vaccine and antibody may sometimes be in short supply.
Whatever happened in India, the woman was reportedly turned away twice by doctors back home at Darent Valley Hospital in Dartford, Kent. It's not clear why, and an investigation is underway, but it's not necessarily surprising since signs of rabies can be very vague at first. Initial signs could mimic a range of minor illnesses, and if the doctors didn't know that the woman was bitten by a dog in India, rabies presumably (and reasonably) wouldn't be considered, especially since it's not present in the UK.
In what is hopefully a case of misquoting or misinterpretation, Dr. Ron Behrens of the London School of Hygiene and Tropical Medicine is quoted as saying that there is a 24 hour window after a bite when antibody treatment can prevent the virus from entering the nervous system. In reality, it's not that quick and the incubation period can be very long in some cases. Post-exposure treatment can be highly effective even if it's given well after exposure, as long as it's before signs of rabies occur. Prompt treatment is always best.
Just as I was getting ready to write about a recent case of travel-associated rabies in the UK, a second suspected case has been identified in the UK. They're not linked and it's just a co-incidence that the two have been identified in a short period of time, but they highlight the potential risks of rabies during travel.
The first report is about a confirmed case of rabies in a woman in her 50s who was bitten by a dog in India. At last report, she was being treated in hospital, although the prognosis is presumably extremely poor if treatment was started after the onset of disease. Public health officials have investigated people who were in contact with the woman to determine who needs post-exposure treatment.
There's not much information in the most recent report, beyond the fact that a suspected rabies case was detected in a person in Leeds following a dog bite that occurred abroad. There's no information yet (at least that I've seen) about where the bite occurred, the condition of the patient or whether the person received medical care after the bite.
While travel-associated rabies is very rare, it's almost always fatal. It's almost 100% preventable too, and any cases that occur typically reflect a breakdown in knowledge, communication or medical care.
Knowledge/Communication: People need to know about rabies, and be aware that any bite from a mammal in a rabies-endemic area should be investigated as a potential rabies exposure. They need to know about the risk of rabies in areas they visit, and avoid situations that might lead to a bite. Travelers and non-travelers alike need to know to go to a physician after any bite and to ensure that rabies exposure is duly considered. Individuals traveling abroad need to know how to access the healthcare system where they are, communicate the problem and act as their own advocate to make sure things are taken care of properly.
Medical Care: With proper post-exposure treatment, rabies is almost 100% preventable. The problem is getting the treatment in a timely manner. Knowing to go to a doctor is one issue. Getting proper care once there is another, particularly in some countries where access to rabies vaccine may be limited or where the healthcare system is poor. Rabies exposure is a medical urgency, not an emergency (although the more severe the bite and the closer to the head, the more important it is for a prompt response). If someone has had a potential rabies exposure and they aren't getting proper care, they need to get home (or somewhere else) where they can obtain the appropriate treatment. That doesn't mean panicking and getting on the first flight out of the country, but it also doesn't mean waiting until your planned vacation is over. It means getting home in good time, while not freaking out if it takes a day or two.
Fox / dog / human, North Carolina
In this case, a rabid fox had a "direct encounter" with several people, then it was killed by a dog. Three people have started post-exposure treatment.
- The article states that the dog was vaccinated against rabies, which is good to hear. However, it goes on to say that exposed pets need to be euthanized or have a 6 month quarantine. In reality, standard guidelines are that unvaccinated pets are treated like this while vaccinated pets undergo a less rigourous 45 day observation at home. Hopefully the discrepancy is simply due to inaccurate reporting and not misinterpretation of guidelines by local officials.
Cat / human, Maryland
A rabid stray cat scratched five people, who have been urged to undergo post-exposure treatment. Officials are calling for anyone who potentially had contact with this cat go to an emergency room.
- However, odds are if someone goes to an emergency room and says they might have had contact with this cat, they're just going to sit around until someone tells them they don't know what needs to be done, or to go home and deal with someone else. Rabies exposure is a medical urgency, not an emergency. People should take a little extra time to work with their physician and/or public health rather than go to the emergency room.
- People who may have had contact with the cat need a proper assessment to determine if they were potentially exposed to rabies, since just being around the cat or having casual contact is not a risk. Scratches are a bit controversial since they are low risk for rabies transmission (unless the scratches become contaminated with saliva from the animal), and there are conflicting guidelines regarding what to do for a person who is scratched.
- This is also a good reminder to stay away from stray cats.
Fox / human, Pennsylvania
In this report, authorities are trying to find a person that cradled an injured fox in a blanket. The fox was subsequently identified as rabid and they need to determine whether the person was potentially exposed to the virus.
- Again, another reminder to stay away from wildlife, and if there is contact with wildlife, make sure rabies exposure is considered.
Bat / human, Indiana
A student was bitten by a rabid bat while he slept in an Indiana University dorm room. He woke up after being bitten (good thing, since he probably wouldn't have noticed otherwise due to the often tiny marks left by a bat bite). He is now receiving post-exposure treatment.
Rabies isn't going away, at least any time soon. People need to be aware of the risks in rabies-endemic areas, take care around wildlife and vaccinate their pets.
Photo credit: Rob Lee (click for source)
Identification of the strain of rabies in the first person in Toronto to be diagnosed with rabies in the past 81 years has essentially confirmed that the infection was acquired abroad. Toronto Public Health has indicated that the strain obtained from the infected man is one known to circulate in dogs in the Dominican Republic, where the man had been working over the past few months.
Little additional information is being released, including whether the patient is alive (and if so, what his condition is). As part of the typical rabies investigation, 15 healthcare workers and an unknown number of family members and friends have been deemed to have been potentially exposed to rabies from the man and have been offered post-exposure treatment. The risk of human-human transmission is exceedingly low, but given the severity of disease, the logical approach is to err well on the side of caution when considering post-exposure treatment.
While rabies strain typing supports a dog bite as the source, that can't be confirmed at this time since the man was too ill to provide any information by the time rabies was being investigated. Sometimes, exposure is determined indirectly based on information from friends and family (e.g. the person mentioning that he was bitten by a dog) and presumably there is an effort to question people who had contact with the man in the Dominican Republic to try to piece this story together.
Toronto Public Health has confirmed the diagnosis of rabies in a person in the city of Toronto, the first such diagnosis since 1931. Details are limited at this point, but there appears to be strong suspicion that this is a travel-associated infection.
The affected person is a 41-year-old man who was working in the Dominican Republic as a bartender. He reportedly started to develop signs of illness last month - it's unusual for someone to be clinical ill due to rabies for so long, as typically once signs occur they progress very rapidly (and almost always end in death). Regardless, after he became sick in the Dominican, he returned home to Toronto, presumably for more medical care. He was taken to hospital by police after arrival since he was behaving erratically at customs. It's reported that he had fairly serious signs before leaving the Dominican Republic, including trouble swallowing and fear of food, water and air. Given that, I'm amazed that he was allowed onto a plane, even with the pretty lax approach that airlines typically take towards sick people boarding planes. While I know circumstances can be difficult and options may have been limited, this isn't really a good way to bring someone home from a foreign country with an unknown disease. Fortunately, rabies isn't spread by casual contact, but you have to consider the potential for more easily transmitted diseases when you go ahead and put someone on a plane with lots of other people. Thankfully his erratic behaviour started on the ground, not in the air, and he didn't have a more transmissible disease.
The man's current condition isn't clear. It appears that the diagnosis was made a few days ago and he's being treated in hospital. However, rabies is almost invariably fatal, especially when disease is advanced by the time it's diagnosed.
People who have had contact with the affected man are being evaluated to determine who requires post-exposure treatment. Further testing will be done on the virus to see what strain it is, to provide more information about the possible origin. Most likely, it was from a dog bite, but that's just a guess on my part.
While little information is available regarding this case, it's a chance to remind people again of a few key rabies prevention points:
- Pets should be vaccinated against rabies.
- People (especially kids) should be taught basic bite-prevention practices and to avoid strange animals.
- Any bite from an animal needs to be investigated to determine whether there might have been rabies exposure.
- Rabies is very common in many countries (especially less developed countries), particularly dog rabies. People need to pay extra attention to bite avoidance when traveling.
- Rabies is basically 100% preventable if proper post-exposure treatment is provided. The weak link is often people failing to seek medical care after a bite. That's particularly true for many travelers. If you are bitten while traveling, you need to make sure you get adequate care, or get home to get treated properly, and promptly.
Don't tell Samuel L. Jackson (Snakes on a Plane was bad enough), but on August 2011, a bat was found flying through the cabin of a plane shortly after take-off from Wisconsin. Failing to heed the seat belt sign, it flew around the cabin a few times before it was eventually trapped in a bathroom. The aircraft then returned to the Wisconsin airport...vnot sure whether that was because they were worried about the bat or because they didn't have an available bathroom any more.
Unfortunately, when they got back to the airport, no one thought to close the plane door before opening the bathroom door, so the bat flew out of the bathroom, out of the plane, down the jetway, through the airport and was last seen exiting the airport via automatic doors (smart bat). The problem with the bat's escape is there was then no way to determine whether it was rabid, since even bats with a good sense of direction can be shedding the virus. Because of that, it had to be assumed that the bat was rabid and an investigation ensued.
The Wisconsin Department of Health called the CDC for assistance and a standard investigation was undertaken. A key component was to determine who, if anyone, was potentially exposed to rabies, assuming the bat was carrying the virus. Rabies is spread through direct contact of saliva from an infected animal with broken skin or mucous membranes (e.g. mouth, nose). Most often, this occurs via a bite. Being in the same area as a bat doesn't constitute a risk.
A rabies investigation typically involves interviewing people who were in the same area as the bat to see if they had any contact with it. That was done, but it was complicated by "difficulties obtaining an accurate passenger manifest...". (Considering it seems like I have to do everything short of depositing a DNA sample to fly to the US these days, I can't fathom how they couldn't have a list of who was on the plane.)
Anyway, the airline gave the CDC a list of 15 people that they knew were on the plane and 33 who had reservations (but apparently they didn't know for sure whether they were on the plane). Considering 50 passengers were on the plane (not counting the bat), that left a few unknowns, which was compounded by their finding that some people who had reservations confirmed they were not on the plane. They tried various ways to contact people, but ultimately ended up with 5 mystery passengers.
Fortunately, the risk of rabies exposure in this case is low. All 45 of the contacted passengers reported having no direct contact with the bat, and it's very unlikely anyone else did given the description of what happened. Similarly, none of the pilots (hopefully it was easy to figure out who they were) and other flight or ground crew reported any contact.
An environmental assessment was performed to see if there was a bat problem at the facility, and nothing out of the ordinary was found. They made a few recommendations to reduce the chance of this happening again:
- Use of netting to cover crevices in the airport where bats might roost.
- Extending and retracting jetways before the first flight of the morning (I guess to scare the bat out before a plane is hooked up).
- Training employees on bat capture methods.
- Testing any bats for rabies.
So, it was more of an interesting story than a true disease concern, but with rabies, you have to be thorough to convince yourself that there's no risk.
It also seems like this bat was much more organized than the airline.
As we've discussed previously, rabies has been a big problem in Bali since 2008. Previously rabies-free, this densely populated island has been struggling with a large and persistent canine rabies outbreak that has resulted in numerous deaths and much debate about control measures.
- Dog bites are very common on the island, with a daily average of nearly 100 bites reported over the study period. Since many bites don't get reported, even this large number is an underestimate.
- The average age of affected people was 36 years, with a range of 3-84 years. All 104 died.
- Most of the cases (57%) were male. This is common, although whether it is because men are more likely to be bitten (because of greater exposure or greater provocation) or less likely to seek medical care after a bite is not known.
- There was a history of a dog bite in 96/104 infected people. It's likely a bite occurred for the others as well, but in those cases the patient was unconscious at the time rabies was suspected and family members did not know of any bites.
- The incubation period ranged from 12 day to 2 years. It was less than 1 year in 98% of cases. Very short incubation periods, like the 12 day one reported here, are almost always associated with bites to the head or neck, since it's a shorter distance for the virus to travel up nerves to the brain.
- Early signs of disease are often vague. Pain or numbness at the location of the bite (37%), nausea or vomiting (30%), fever (22%), aches (17%), headache (16%) and insomnia (7%) were most common.
- 81% of people that developed rabies did not undergo any type of treatment. 11% washed the wound themselves. Only 6% went to the hospital on the day of the bite. The people who went to the hospital received a course of rabies vaccines but did not receive rabies immunoglobulin (RIG, which is anti-rabies antibodies). So, while they were treated, they didn't get the full recommended treatment. This is incredibly frustrating since rabies is almost 100% preventable if people get proper medical care. Failure of most of these cases to even seek care is a huge issue, and inadequate treatment of people who sought medical care compounds the problem. Not all of the vaccinated people completed the full vaccine course before developing signs of rabies. These were individuals who had short incubation periods because of bites to the head and neck.
These results are not surprising but demonstrate a few important concepts, including:
- the need for education of the general public to seek medical care after a bite.
- the need for proper education of healthcare providers so that people who are bitten get proper medical care.
- the need for adequate supplies of rabies vaccine and immunoglobulin. It wasn't stated whether people didn't receive RIG because it wasn't offered or (as is common in some regions) it wasn't available.
- rabies may not be considered initially when signs first start appearing, as many of these people ended up being treated for various other potential problems before rabies was considered. While rabies is almost always fatal, there have been very few "successfully" treated individuals (meaning they didn't die, but they can still have long-term neurological impairment), but to have any chance at success, treatment needs to be administered as quickly as possible.
- control of canine rabies is a key part of controlling human rabies.
Max, a 12-year-old Chihuahua from Greenfield, New Jersey, was euthanized recently after he was exposed to rabies. While far from unusual, the case highlights the ongoing risk of rabies exposure as well as issues with understanding of rabies guidelines and communication.
Max was attacked by a rabid raccoon - an ever-present risk for animals that go outside (or get outside) in many regions. Animal control was called and the raccoon was caught. It was euthanized and rabies was confirmed, indicating that Max was very likely exposed to the virus.
Here's where things seem to get strange. The paper reports:
"Once exposed to a rabid animal, a six-month quarantine is required for the exposed animal, even those animals that have been inoculated with a rabies vaccine."
- Not really. In Canada, standard guidelines are for a 6 month strict quarantine for dogs (and cats) that are not properly vaccinated, but only a 45 day observation period is required for vaccinated animals. I don't know if in this jurisdiction they made up their own different rules, whether someone doesn't know what's supposed to be done or whether it's poor reporting, but it's a concern because it can be a difference between life and death... not necessarily from rabies, but from the quarantine requirements alone. People are often unwilling to undertake a strict 6 month quarantine and choose euthanasia (as was the case here), while the 45 day observation period is much more acceptable.
The attending veterinarian stated "Because of the way it was exposed and because of the positive, I think there was a really good chance this dog was going to get rabies".
- It's certainly possible, and nowhere does it say whether Max was properly vaccinated. However, there's a reason we vaccinate. It's a highly effective vaccine and we're trying to prevent disease. Nothing's 100%, but with proper vaccination, the risk of rabies is greatly reduced.
It's also stated that "due to the nature of rabies, until behavioral changes occur, the animal is not infectious".
- While this doesn't have anything to do with Max's situation, it's not true. Animals can shed the virus for a short period before they show signs of illness. That's the reason there is supposed to be a 10 day quarantine period after a dog bites someone - to see if the dog develops signs of rabies (which would have major implications for the person who was bitten).
Curiously, the article ends with a reminder to vaccinate pets, which seems kind of strange if their assumptions are that an exposed animal will get sick irrespective of vaccination status and that vaccination will have no impact on what happens to an animal after exposure.
However, despite the miscommunication, the take-home message emphasizing the need for vaccination should be heeded. As well, people making decisions about what to do after rabies exposure should make sure they do so based on the best evidence that's available, namely the Compendium of Animal Rabies Prevention and Control.
The Ontario Ministry of Natural Resources and Welland SPCA are warning people about an apparently large number of cases of distemper in raccoons in the area. Distemper is a pretty nasty disease which can be spread between dogs and wildlife. It’s caused by canine distemper virus, but the "canine" part of the name can be a little misleading, since this virus readily infects some other species such as raccoons.
In addition to the problems with sick and dying raccoons caused by the outbreak, there are two main concerns for pet dogs:
One concern is the potential for wildlife to transmit canine distemper virus back to dogs. It’s hard to say what the risk of that is, and the risk would be primarily to young dogs that are not adequately vaccinated. If a dog has an encounter with a raccoon that is sick with distemper, it’s possible the pet could be exposed to the virus. Dogs are also probably more likely to have close encounters with sick raccoons that are unable or unwilling to run away, as opposed to healthy raccoons. If an inadequately vaccinated dog gets exposed, it can get very sick, which is obviously bad for the dog, and also creates another potentially infectious animal to keep passing the virus along.
The other concern is differentiating distemper from rabies. Distemper can cause signs that are very similar to rabies. If a dog has an encounter with a raccoon that is behaving abnormally, rabies is a big concern. If a dog is exposed and the raccoon is not available for rabies testing, the dog would require a 6-month strict quarantine or euthanasia if it's not vaccinated (or not adequately vaccinated), or a 45 day "observation period" (on a proverbial tight leash) if vaccinated. These measures aren’t easy to implement, and unvaccinated dogs often end up being euthanized because owners don’t want to go through the hassle of a 6 month quarantine.
What does this mean to the average pet owner? Well, nothing that they shouldn’t be thinking about anyway. This just increases the relevance of some routine measures such as:
- Keeping dogs that are outside are under control so they don’t encounter wildlife.
- Ensuring dogs are properly vaccinated against distemper and rabies.
- Taking particular care to prevent exposure of young unvaccinated dogs to wildlife.
- Discouraging raccoons from taking up residence in yards.
Nothing earth-shattering, but these basic precautions can greatly reduce the risk of disease transmission from wildlife to dogs, be it rabies, distemper or other bad bugs.
While rare, Morocco continues to be a source of rabies in European animals. The latest case involved a puppy imported into the Netherlands. The (somewhat) brief version of what happened goes like this:
- On Jan 28, 2012, a Dutch couple bought an 8-week-old puppy in a parking lot in Morocco. The puppy was taken to a local veterinarian, microchipped and given a certificate of good health. It would have been too young to vaccinate against rabies.
- On Feb 4, the couple travelled from Morocco to Spain by car and ferry. They then obtained a European pet passport from a Spanish vet, despite the fact that the dog was not vaccinated against rabies (an EU requirement for a pet passport).
- On Feb 11, they returned to the Netherlands. Customs officials "cuddled" with the puppy but apparently didn't ask about rabies vaccination. When they got home, the couple exposed the puppy to many family and friends.
- On Feb 14, the puppy started to become aggressive. They contacted a veterinary practice, and it was assumed the problem was stress, so a sedative was given. (It's not clear whether the puppy was actually examined. If not, that's a pretty big mistake.)
- On Feb 15, the puppy was uncontrollable. The report states "When they realized that the puppy originated from Morocco, the veterinarians contacted the Netherlands Food and Consumer Product Safety Authority (NVWA)." The puppy's history should have been a basic question asked when the couple first contacted the veterinary practice about the animal. Regardless, the concern about rabies came to the forefront with that information, and the puppy was euthanized. Rabies was confirmed that evening (a pretty impressive turnaround time for rabies testing).
- As is typical, an investigation was launched, and a search for people who had contact with the puppy during the period when it was potentially infectious was started. That's not easy when it involves multiple countries, as was the case here, since the potentially infectious period is 10-14 days prior to the onset of clinical abnormalities. The potential contacts included the Moroccan veterinarian, some friends in Spain, the Spanish veterinarian, three customs officials, a couple of unknown people in a Spanish restaurant and at the Malaga airport, and 43 people after arrival in the Netherlands (plus an unknown number of people who petted the puppy on the street).
- Contact doesn't mean exposure, since rabies isn't transmitted by casual contact, so the type of contact was queried further. The risk is from bites or contact between the dog's saliva and broken skin or mucous membranes (e.g. mouth, eyes). Because of concerns that kids don't accurately recall the type of contact they have (meaning they might fail to mention a little nip or some other high risk contact), all nine children who had contact with the puppy were given post-exposure prophylaxis. The Dutch friends in Spain reported high risk exposure and were also treated, however they had to return to Amsterdam for full treatment since anti-rabies immunoglobulin (antibody) was not available in Spain. Information was provided to Moroccan officials but information about what happened there wasn't available.
- Overall, it is stated that 45 people needed post-exposure treatment (although who those 45 were isn't really clear). That's a pretty large exposure, resulting is much angst and expense.
- Two cats and a dog were also exposed to the puppy. The dog had been vaccinated, and received a booster. (It would also be standard protocol to quarantine them for 45 days as well, but that's not stated.) The cats were euthanized because a "suitable quarantine place was not available," a rather strange statement since quarantine isn't a very high tech procedure.
Obviously, this is of relevance to people that live in Morocco or are going to get a dog from Morocco. Those people need to be aware of rabies, be careful when getting a pet, ensure their pets are properly vaccinated against rabies and be careful around stray animals. This report also highlights a couple of other issues:
- A parking lot isn't a good place to buy a puppy, for many reasons. A reputable breeder isn't going to sell a puppy there, and there are lots of good, well-evaluated puppies available through good breeders and shelters.
- Pet importation requirements are pretty weak in a lot of ways, especially if no one actually pays attention to them. That seems to be a recurring theme as well with these imported rabies cases. Here, the puppy was given a European dog passport without the required rabies vaccination, and was not kept in quarantine after arrival. It also went through no less than three customs points in transit, where no one queried rabies vaccination status. The mandatory 3 month quarantine would have prevented exposure of most of the people that required post-exposure treatment.
- Visitors to areas where rabies is endemic in the dog population need to be aware of it. Encountering stray dogs isn't exactly rare in many countries, and while staying away from strays is a good general rule everywhere, people should be particularly careful in areas where the risk of rabies is high. Travelers also need to be aware of what to do if they are bitten by a stray animal.
The parents of a US soldier who died of rabies after being bitten by a dog while deployed in Afghanistan want their son's superiors to be held accountable. Specialist Kevin Shumaker died last August, eight months after being bitten by a dog. An Army investigation concluded that he died because members of his unit ignored rules prohibiting keeping pets (they were befriending feral dogs) and that he didn't seek treatment or notify the chain of command after being bitten. His parents feel that their son is being falsely blamed and that people who should have known better didn't do their jobs. It's a complex issue with some interesting questions.
What should the average soldier know about rabies?
It should be assumed they know absolutely nothing to start off, and a risk assessment should be performed for each deployment to determine what they need to know. When they are being deployed to a rabies-endemic area, they need to learn to stay away from dogs and report dog bites promptly, and why.
Whose job is it to report a bite?
At the end of the day, everyone has to be their own advocate and make sure they report any possible rabies exposure. People up the chain of command don't see everything and individuals need to protect themselves. However, once the bite is reported, others have to act. That might be the breakdown here.
Was anyone actually notified?
The Army's investigation actually documents the fact that Spc. Shumaker notified other personnel at least twice. One was a veterinary corps officer and the other was the person doing his post-deployment health screening. Here's where the ball was probably dropped. Every veterinarian knows about rabies. A veterinarian working in a rabies endemic region is certainly aware of the risks and has a responsibility to act on a reported bite. I find it astounding that a veterinarian in this situation wouldn't initiate a response, particularly given the fact that (at least in my limited experience) the US Army Veterinary Corps has some excellent veterinarians, so this seems rather strange. Further, what's the purpose of a post-deployment health screening if health issues that arise are ignored? If the person doing the health screening didn't understand the concerns about rabies, he or she was inadequately trained and shouldn't have been doing the job. If the screener was properly trained and didn't report it, he or she was incompetent, plain and simple.
Would anything have changed the outcome here?
Absolutely. Rabies is almost 100% fatal, but it's almost 100% preventable when post-exposure treatment is given before the onset of disease. There was lots of time in this case between the bite and when the soldier became ill, and if he had been treated following one of these reports, you can almost guarantee he would not have developed rabies.
Whose fault is this?
Well, everyone plays a role here. The soldier ignored the animal contact rules. Superior officers on base presumably ignored the fact that they were ignoring the rules, probably not thinking about the possibility of rabies, and seeing the positive effect on morale of interacting with the dogs. If the veterinary officer and post-deployment health screener were told about the bite and did nothing, they played a huge role since they, of all the people in this chain, should have known better.
What should happen here?
Rather than fighting over who's to blame (the usual response), an investigation should figure out why this happened and how to prevent it from happening again, largely via better training and clear expectations of personnel.
Hopefully that's happening, since Deputy Commanding General Maj. Gen. William Rapp recently approved a series of recommendations, including:
• Further investigation to see if any members of the unit should be disciplined for their actions or omissions during the unit’s deployment to Afghanistan
• Institute an animal-borne disease surveillance program, standardize rabies vaccine requirements and improve dog bite reporting requirements (I'm surprised that wasn't already the case)
• Reinforce animal bite and rabies training for veterinarians and post-deployment health screening staff
Rabies is pretty rare in horses in North America, with only 37 reported cases in the US in 2010 and 1 in Canada in 2011 (the latest years for which data are available). So, finding two apparently unrelated cases of rabies in horses in the same area in the same month is pretty unusual and concerning. Yet, that's what's happened in Tennessee, where rabid horses were identified in both Rutherford and Marshall counties in January.
Little information is available about the cases, but both were identified as having the skunk rabies virus variant. That doesn't necessarily mean they were infected by skunks (since other species can be infected by this virus variant) but it is suggestive, and indicates that rabies must be active in the skunk population in that region.
Regardless of the source, these cases are a reminder of why rabies vaccination of horses is important, and why rabies vaccination is considered a "core" equine vaccine by the American Association of Equine Practitioners. Rabies is invariably fatal in horses and it's also a major public health risk. While I've been unable to find confirmed cases of horse-to-human rabies transmission, it's a possibility, and additionally, rabid horses have killed people because of their unpredictable and aggressive behaviour.
Vaccination is cheap insurance against rabies - it's never a 100% guarantee, but it's a whole lot better than without vaccination.
The unfortunate victim was a 73-year-old Haitian women. She initially went to an emergency room with a complaint of right shoulder pain, chest pain, headaches and high blood pressure. Difficulty swallowing was also noted when she was given pain medications, but she declined further testing and was discharged. It's not surprising that rabies wasn't considered at this point, although I doubt she was asked about animal contact or animal bites as a routine history question.
The next day, the woman went to two different emergency rooms, complaining of shortness of breath, spasms, hallucinations and balance problems. A cause was still not readily apparent, and over the next couple of days, her condition deteriorated, with development of more neurological abnormalities including tremors and mild seizures. Encephalitis (inflammation of the brain) was diagnosed, and a range of potential causes were ruled out. A nuchal skin biospy was collected for rabies testing but she was declared brain dead by the time results were obtained.
The strain of rabies that was identified most closely matched a canine rabies virus variant from a person in Florida who acquired rabies in 2004 while in Haiti. Upon further investigation, a cousin recalled that the person had been bitten by a dog in Haiti a few months earlier. The bite wasn't considered severe and medical attention wasn't sought.
As an almost invariably fatal infection but an almost completely preventable disease with proper medical care, education is a key aspect of rabies control, and that's where most of the breakdowns occur. This person didn't seek medical attention after the bite, because the bite wasn't too severe. Unfortunately, mild bites can transfer rabies just like severe bites, and any bite needs to be investigated as a potential source of rabies, particularly in highly endemic areas.
Canine rabies is a major problem internationally, accounting for tens of thousands of human deaths each year. Canine rabies has been eradicated in the US, meaning the canine rabies virus strain is no longer circulating. That doesn't mean dogs in the US can't get rabies, since they can be infected with various wildlife strains, but there is not a circulating pool of canine rabies virus like in some other regions. Canine rabies is still endemic in Haiti, although there have been efforts to control it through education and vaccination of dogs and cats in the country (where less than 50% of dogs and cats are vaccinated).
People living and traveling to rabies-endemic regions like Haiti need to be aware of the potential risk of rabies and consider any dog bite a possible rabies exposure. Similarly, healthcare workers need to query animal exposure and animal bites as a routine practice, since as with this case, rabies can be hard to diagnose initially.
Following on the heels of a case of bat-associated rabies in a South Carolina woman, a Massachusetts man has contracted rabies. Little information is currently available, although authorities state that they believe he was exposed by a bat in his home. News reports state that he's in critical condition but it's unfortunately very unlikely that he'll survive. Family members are receiving post-exposure treatment, however it's unclear whether this is because of concern for exposure from the infected man, or from the bat.
While these two cases don't represent a rampant rabies epidemic, it shows that there is still a long way to go with education of the public about bats and rabies. Rabies is a disease of extremes. It is essentially 100% preventable in people if exposure is identified and managed properly. It's also almost invariable fatal once disease sets in.
It seems like pet bite articles come in waves, with a recent cluster showing the variable quality in advice that's available.
Often, they are holiday "filler" articles that provide some basic useful information but overall are of limited use or even harmful based on their very superficial approach. They often mention rabies, get a quick quote from a veterinarian or someone in public health, but don't emphasize the potential problems that can occur with even apparently minor bites. The thing that often raises my ire is the common statement about watching the bite and going to a doctor if your limb swells up or has pus oozing out, without talking about the need for proper post-bite care to actually prevent that from happening.
Anyway, I came across a couple of better articles recently, that get some good information across in a nice, readable manner. One, an article in "The Herald News" entitled "Cat bites always require check by doctor", gets a very important point across quickly.
The news story details the saga of the PJ, a 13-year-old cat, and his owner. PJ bit the woman on the arm causing a seemingly minor wound, but by the next day, her arm was red and swollen, necessitating a round of intravenous antibiotics and four days in hospital. In the article, Gail Steele, an infection prevention nurse, states "Cat bites.. must always be considered medical emergencies. This is especially true when they occur in the hand because that area has a richer blood supply...Their sharp little teeth are like little needles, and they inject bacteria right into soft tissue..."
This is a pretty extreme example of what can happen after a cat bite, but it's far from rare. It's not really clear whether this person's infection would have been prevented with normal practices. Bites over certain sites, like the hand, foot, joints, tendon sheaths and prosthetic devices, and bites to young kids, elderly individuals and people with compromised immune systems typically require prophylactic antibiotics.
If this was actually a bite over the arm, as reported, antibiotics might not have been given, even though cat bites are much higher risk for infection than dog bites. However, the key is that bites should be assessed so proper determination can be made about the need for antibiotics. All infections won't be prevented but appropriate medical care should reduce the risk and also allow for adequate consideration of whether rabies exposure might be a concern.
There's a sad end to this article, as PJ bit his owner again a few months later. The bite was over the shin and, given her previous problems, antibiotics were provided. However, the owner still ended up with an abscess that required surgical intervention and took months to heal. (Whether this person has really bad luck, whether PJ has a particularly bad mix of bugs in his mouth or whether the owner has an unidentified problem with her immune system is unclear, but back-to-back severe infections is a major issue, especially with a cat that is prone to biting.) The woman's daughter ended up taking PJ home with her, but after another unprovoked bite, he was euthanized.
Cat bites aren't always this bad, and in fact, most don't result in complications. However, that's not to downplay the potential problems. When you consider how often cats bite, how often cat bites are not properly cared for because they appear to be minor, and the ability of a cat bite to inoculate bacteria deep into the tissues, it's easy to see how bad things can happen. Reducing the risk of cat bite infections involves a few basic steps:
- Reducing bites. Good handling and training (of both cats and people) can reduce the likelihood of bites. This is particularly important with kids, who may be bitten through rough or excessive handling of a cat.
- Bite first aid. Prompt cleaning of the wound can reduce bacterial contamination. Thorough cleaning with soap and water can have a big impact on the likelihood of infection.
- Medical care. Bites over certain sites or to certain individuals (see above) almost always require antibiotics. There's less consensus over other types of bites, but getting medical care is a good idea in any case to determine if there are any factors that indicate a need for antibiotics.
- Rabies avoidance. Every bite should be reported to public health so the rabies aspect can be covered. The biting animal needs to be identified and observed for 10 days. If it's healthy after 10 days, it couldn't have been shedding rabies virus. If the biting animal cannot be identified, it's likely that post-exposure treatment for rabies will be required.
Marion County (Florida) public health personnel recently issued a rabies alert after a horse in the area tested positive for the virus. It’s a standard alert, emphasizing avoiding contact with wildlife, reducing things that attract wildlife to houses (e.g. accessible pet food or garbage) and recommending vaccination. Interestingly, while this alert was prompted by a case of rabies in a horse, it only mentions vaccination of dogs, cats and ferrets. That may have been because it was an off-the-shelf alert, not really tailored to this situation, but it shows how horses can be overlooked when it comes to rabies.
Fortunately, rabies is a rare disease in horses. In 2010, there were 37 reported cases of equine rabies in the US and only one in Canada (two Canadian cases have been identified so far this year). That’s a very low rate, especially considering the number of horses out there, but it’s still more cases than there should be for a very serious yet highly preventable disease.
Unfortunately, rarity sometimes breeds complacency, so despite the fact that rabies is invariably fatal in horses and rabid horses pose a risk to people, vaccination of horses is often overlooked. While rabies is rare in horses, rabies vaccination shouldn’t be rare. Every horse in a rabies endemic region (or that might be traveling to such a region) should be vaccinated against rabies. It’s cheap insurance against a very dangerous and deadly disease.
A South Carolina woman has been identified as the first case of human rabies in the state in the past 50 years. Very little information has been released, including whether or not she is still alive. Unfortunately, the odds are quite low that she survived. Successful treatment of a Wisconsin girl in 2004 using a radical new protocol was accompanied by much optimism for treatment of this disease, which at the time was described as invariably fatal. While a few other survivors have been reported, rabies is now often referred to as almost invariably fatal, since the protocol has not been the panacea that it was hoped to be, and death is still the typical outcome.
In the latest case, exposure to a bat in the home a few months earlier was the suspected source of infection. This is a common source of exposure and a typical time frame. Few details are presented, so it's not clear whether the woman was known to have been bitten by the bat or whether that's suspected for some other reason (such as lack of other possible sources).
This is another indication of the care that needs to be taken around bats. While human rabies is fortunately very rare in Canada and the US (it causes tens of thousands of deaths each year worldwide, mainly from dogs in a few developing countries), bats are an important source of exposure. Any encounter with a bat needs to be accompanied by a determination of whether there is a risk of rabies exposure. Anyone bitten by a bat should try to make sure the bat is caught and tested for rabies, because otherwise there's no way to prove it wasn't rabid, and post-exposure treatment would be indicated.
Image: Bat bites can be very dangerous, because they carry the risk of rabies transmission, but they can be so small that they may not even be detected. (Image source: http://agrilife.org/batsinschools/responding-to-a-bat-bite/)
The Toronto Star has an article describing the efforts of Naz Sayani to bring home a group of street dogs from India. As an animal lover, she was touched by the number of stray dogs roaming around New Delhi while accompanying her daughter to India for medical treatment. She borrowed a car and started driving around the city dropping off food for strays.
- This is a high-risk activity for rabies exposure. Rabies is very common in India and contact with strays is a prime source of human infection. Ideally, anyone working with strays should be vaccinated against rabies. At a minimum, they should be aware of the risk and be ready to get post-exposure treatment if exposed (possibly through a quick trip out of the country, since knowledge about rabies prevention and access to rabies post-exposure treatment is variable in India).
A pregnant stray dog caught Naz's eye, and after hearing about people threatening or abusing the dog (and later her and her pups), she tried unsuccessfully to find them homes. Eventually, she made the decision to bring them to Canada, in order to try to find homes for them here.
I can certainly see how this would happen, as it's easy for people to get attached to a friendly, needy animal. It's also hard to balance a case-based scenario like this, when someone has an attachment to a specific animal, with the bigger picture of animal rescues, and all the associated pros and cons.
I get a surprising number of advice calls and emails from people "rescuing" dogs from various places.
- The typical questions goes something like "I am organizing a rescue of a group of dogs from [insert one of many central or southern US states here] and want to know if there are any infectious disease issues I have to worry about".
- Worse are the calls that go "I just got some rescue dogs from [wherever] and now my other dogs are sick. What might be going on?"
People that are rescuing dogs usually do it because they have big hearts. Some people like the "status" that they see attached to certain rescue dogs ("You have a new Mercedes? Well I have a new Hurricane Katrina rescue dog"). My problem with international rescue efforts is the question of a) whether it's a good use of resources and b) whether it poses unnecessary infectious disease risks to people and other animals.
- Organizing rescues, fulfilling regulatory rules, shipping dogs and finding them homes takes a lot of money. It would make more sense if there was a shortage of adoptable strays in Ontario. However, I haven't heard any shelter personnel lament their lack of dogs, undercrowded facilities or excessive financial resources.
- Moving animals between different regions carries an inherent risk of transmission of infectious diseases. The more movement, the more mixing and the greater the difference in infectious diseases in the areas, the greater the risk of making more animals sick, and potentially doing more harm than good.
- Rabies is one concern, and rabid dogs have been imported into North America in the past. Since rabies has a long incubation period, it's hard to be certain that a dog's not incubating a rabies infection.
- More likely to be imported would be a wide range of other bacteria, viruses, parasites and fungi. These are a concern from several standpoints. Some might cause disease in the imported animal, and diagnosis may be delayed or missed because of it being a disease with which local veterinarians have no experience. Some might bring an unusual pathogen into the area that could be spread to a few other in-contact dogs. Worse, some might bring in a new pathogen that could then establish itself in the local (or national) dog population. We don't know how often any of these scenarios occur, but they are always a risk, and need to be part of the cost-benefit analysis of animal rescue operations and associated animal importation.
At the end of the day, it's hard for me to support rescuing dogs from other regions when we already have a large population of dogs in our own shelters and animal being euthanized here because there are no homes for them. I can't justify the expense and risk of importing dogs if, for every new dog imported, one other dog in a local shelter gets euthanized because it doesn't have a home. Does importation really mean fewer adoptions here? We don't know, but it stands to reason.
A situation like this is a little different, as a chance and presumably (hopefully) one-time event prompted by a specific human-animal bond. Overall though, we could do better for the dog populations both here and in regions where there are massive stray problems by focusing attention on better care and adoption here, and international programs aimed at helping stray populations abroad through vaccination, education and sterilization efforts.
A recent article in the Toronto Sun described one physician's approach to dealing with dig bites in kids. It contains some useful information, but also a couple of areas that probably require some clarification.
In the article, the physician lays out a few points regarding management of dog bites in kids:
The first thing a parent should do after such a bite is to stop the bleeding by applying pressure. Then, clean the area with warm water and soap. Dogs, like humans, have dirty mouths, so you want to wash and rinse well and even flush out the wound if it's deep.
- "The solution to pollution is dilution" is a old adage. Thorough cleaning is a critical step.
If the bite wound is small, it's usually not sutured, as this might increase the risk of infection. On the other hand, facial wounds and larger bites have to be well cleansed and irrigated, and may require stitches. The sooner this can be done the better.
For a child with a dog bite that has broken the skin, most pediatricians would recommend a seven-day course of an antibiotic, typically Augmentin (unless the child is allergic to penicillin).
- I'm not sure "most" doctors would start a child on antibiotics after any bite that has broken the skin - at least I hope not. Typical recommendations for bites include that antibiotics should be considered with moderate to severe injuries, puncture wounds, people with compromised immune systems and bites over specific areas like joints or the face. Antibiotics for minor soft tissue injuries in otherwise healthy individuals are not typically recommended, although there is some controversy.
Rabies is usually not a risk in dogs that are family pets and live in homes. If the dog is not known or their rabies status is unclear and you can't locate the pet, check with your pediatrician about rabies prophylaxis.
- True. Rabies from pet dogs is very rare in North America. However, if you get it, you almost certainly die, so we take precautions even in low risk situations. So, a little more discussion of this point is important.
- Every dog bite must be approached as a potential rabies exposure. Key points for this are identifying the dog and ensuring it's quarantined for 10 days. After 10 days, if it's healthy, it couldn't have transmitted rabies with the bite. Related to this, any dog bite should be reported to local Public Health personnel. They will ensure that quarantine is imposed if the dog is known, and facilitate rabies post-exposure prophylaxis in the rare situations that it is needed. In Ontario, physicians are bound by law to report bites to Public Health.
Dog bites are unfortunately very common. Usually they are minor and heal without much trouble, but serious or fatal injuries can occur and infections are a potential problem. Knowing what to do in response to a dog bite is important to reduce the risk of a range of complications.
The CDC's annual animal rabies surveillance report has been published in a recent edition of the Journal of the American Veterinary Medical Association (Blanton et al 2011). It's the regular synopsis of the state of rabies in domestic animals and wildlife in the country. It contains some interesting information but few surprises. Among the highlights:
- Rabies was identified in 6154 animals in 48 US states, plus Puerto Rico. The true number of animals that died of rabies in the year would have been much higher, since not all animals (particularly wildlife) that die of rabies get tested.
- 92% of positive animals were wildlife, including raccoons (37% of cases), skunks (24%), bats (23%) and foxes (7%).
- Cats were the most commonly affected domestic animal, accounting for 4.9% of cases (303 cats), followed by cattle (1.1%), dogs (1.1%) and horses (0.6%).
- Different rabies virus variants predominated in different regions. For example, raccoon rabies virus was most common on the east coast. Different skunk rabies variants predominated in the south-central and north-central regions, along with California and Nevada. A couple of pockets of fox rabies were present in the southwest, along with one in Alaska. Mongoose variant was present in Puerto Rico. Bat variants were spread out across the country.
- Most rabid cats were from states where raccoon rabies is endemic. About 1/3 of infected cats were from Pennsylvania and New York. Texas was the leader in dog rabies, followed by Puerto Rico and Virginia.
- Two cases of rabies in humans were identified, compared to 4 in 2009. One was a migrant worker infected by a vampire bite while in Mexico. The other was a man from Wisconsin who was infected with a bat rabies strain. Both died.
Canadian and Mexican data are also reported:
- 123 cases of rabies were identified in Canada, 93% of which were wildlife. 7 (5.7%) were dogs or cats. No rabid raccoons were identified, continuing a trend that has been observed since 2009. Bats and skunks were the wildlife leaders. No people were infected.
- 357 cases were reported in Mexico. 83% were cattle, 20 were dogs. Four human cases were identified.
While rabies does not exert anywhere near the impact on people in North America compared to many other regions (where tens of thousands of people die from the disease every year), it continues to take its toll on wildlife and, to a lesser degree, domestic animals. It's also a preventable disease that can be controlled with vaccination, and human cases can effectively be eliminate by proper post-exposure treatment. Continued efforts are needed to reduce rabies in wild and domestic animal populations, for both the protection of those populations and protection of the people who may come in contact with them.
While it's not really an occasion to celebrate, September 28 was World Rabies Day. Rabies has been a problem for millennia, and it's not going away any time soon. This viral disease, which is almost invariably fatal, kills 50 000 - 70 000 people per year. Some countries have astounding rates of rabies cases, such as India where ~20 000 people die of the disease every year. Internationally, most human rabies infections are caused by dogs, but wildlife are the main source in some regions (such as Canada and the US) . Basically all rabies infections are preventable with proper access to good medical care and rabies post-exposure prophylaxis, but sadly the thousands of people who die do not receive treatment.
Is rabies controllable? Yes. With measures to reduce rabies in wild and stray animals, pet vaccination, public education measures, good access to medical care, adequate rabies vaccine supplies and adequately trained healthcare personnel, the incidence of rabies can be dramatically decreased. However, these measures require time, money, effort and political will, and those are limitations in some areas.
Can rabies be eradicated? That's a tough question. Eradicating a disease that can be found in many wild animal species internationally is extremely difficult. It's hard to envision complete eradication of this virus, as was done for smallpox (a human-only disease) and rinderpest (a cattle-only disease). Both those diseases had the advantage of only being found in one species, making control and eradication much more feasible. However, while we might not be able to eradicate rabies, it's certain that tens of thousands of lives could be saved every year with good rabies control programs.
More information about rabies can be found in on the Worms & Germs Resource page.
The latest update on equine infecious neurological diseases in Ontario (Eastern equine encephalitis (EEE), West Nile virus (WNV), rabies and neuropathic equine herpevirus type 1 (EHV-1)) is available from the Ontario Ministry of Agriculture, Food and Rural Affairs.
There aren't a lot of surprises, and it's good to see the numbers of cases have remained relatively low. Most notably, there have been three EEE and five WNV cases confirmed, from different regions of the province. This shows that these diseases are still occurring in Ontario horses, albeit at a very low rate.
You always have to consider the limitations of surveillance data like this. To make the list, a horse has to get infected, get sick enough for someone to notice, a veterinarian has to be called and proper samples have to be taken for diagnostic testing. There's certainly no guarantee that this happens in all instances, and it's reasonable to assume that a few more cases of these diseases have occurred in Ontario this year.
In Ontario, August and September tend to be the months of highest activity for EEE and WNV, and as we move into cooler weather (and decreased mosquito activity) the risk of EEE and WNV will start to plummet. I wouldn't be surprised if the numbers increase slightly by the time the final tally is made, but there are no indications that we have major disease activity at the moment.
Surveillance data such as this, including total numbers of cases in the province and an indication of areas where case occur, are important for horse owners and veterinarians to consider when determining their vaccination programs.
Rabies is pretty rare in horses, but there have been a few reports this summer. Though rare, rabies is still a major concern because it's invariably fatal in horses, and almost always fatal in people.
Rabies was recently diagnosed in a horse in Eddy County, New Mexico. It started showing undefined signs of rabies and was euthanized two days later. Several people who worked with the horse are undergoing post-exposure treatment.
While rabies can potentially be spread from horses to people, I'm not aware of any confirmed cases of such transmission. Since rabies usually kills people, even a plausible risk is cause for concern. Additionally, and perhaps more importantly, rabid horses can be very dangerous, and multiple people have been killed by aggressive rabid horses.
Rabies should be a core component of a horse's vaccination program in any part of the world where rabies is present in the wildlife population. Unfortunately, that's not always understood. One area resident stated she'd never heard of rabies in horses, and while she has her dogs and cats vaccinated, she hasn't vaccinated her livestock. No vaccine is 100% preventative, but rabies vaccination is a cheap and very effective way to reduce the risk of this fatal disease significantly.
A recent case of canine rabies in France showed yet again the risks posed by illegal importation of animals. This case is somewhat unusual since it seems to involve ignorance of the rules and lax enforcement, compared to rampant animal smuggling, but the end result was the same.
The animal in question was a puppy that was brought to France by a family that had been vacationing in Morocco. They found the puppy on July 11 and returned to France on July 31. European Union regulations require that imported dogs be vaccinated against rabies and microchipped. Neither was done to this puppy, and it was in fact too young to vaccinate against rabies according to standard protocols. The family traveled back to France by ferry and car, and either met no customs officials or at least no officials who asked any questions about the puppy.
They day after they returned to France, the puppy started to exhibit behavioural changes and progressive sleepiness, with subsequent development of aggression. Five days later, it was taken to a veterinarian and it died the next day. Rabies was confirmed a few days later, and testing of the virus strain indicated that it was of the Africa-1 lineage and closely related to strains previously isolated in Morocco.
An investigation into possible rabies exposure ensued. Typically, it is assumed that animals can be infectious for up to 10 days prior to showing signs of rabies. Often, this is extended by several days for added confidence and because it's not always possible to determine exactly when the earliest, mildest signs might have developed. In this case, they considered the period that rabies could have been transmitted to be from July 18 until the puppy's death.
Multiple people had close contact with the puppy. Three family members had been bitten, a clear indication for post-exposure treatment. One other person (a friend of the family, it appears) was also bitten and received treatment. Another person reported being licked on non-intact skin (i.e. an area of skin with a cut, abrasion or other break in the normal barrier) and was also treated. The attending veterinarian, who had been previously vaccinated, received two booster shots.
This isn't the first time that rabies has made its way from Morocco to France, and it's concerning that it was so easy for it to happen. Nine rabid dogs have been illegally imported to France from Morocco since 2001. In 2008, one such dog subsequently transmitted rabies to several other dogs, resulting in France losing its rabies-free status until February 2010. It's not surprising that no questions were asked of the family traveling from Spain to France because of the open nature of borders between EU countries, but the ability to enter Spain from Morocco with no flags being raised is a concern. Hopefully there's an investigation into how this puppy was able to get into Europe so easily and how to reduce the chances of this happening again.
China has a huge canine rabies problem, with thousands of human rabies deaths each year. There are several reasons for this, including large feral dog populations, inadequate vaccination of pet dogs, differences in approach and access to veterinary care for pets, inadequate education regarding dog bite prevention, and presumably inadequate education of people and/or healthcare personnel regarding when and how to seek proper post-exposure treatment.
Periodically, the knee-jerk reaction of dog culling rears its head in China, despite the ineffectiveness of culling alone as a rabies control tool.
Recently, authorities in Guangdong province have banned ownership of dogs (in most situations) and given residents until August 26 to get rid of their pets. Dogs remaining at that time will be put down, except for dogs that are used to protect property worth ~ $750 000 (or more). Those dogs must be vaccinated and "kept locked up." (Why the same things (i.e. vaccination and confinement) can't be done with any other pet dog is unclear, since being owned by a rich person doesn't make a dog less susceptible to rabies.)
An expert from the Chinese Center for Disease Control summed up the issue nicely: "This [ban] is not scientific, not humane, and it will not last long. In short term, maybe it could be effective, but after that, people still want to keep dogs."
Culls don't work well. A cull can decrease the population of concern for a time, but it's extremely unlikely that it would reduce the population enough to have any longterm effect. Dogs can reproduce quickly and replace the culled animals in a short period of time.
What would make more sense?
- Widespread vaccination of pet dogs, to reduce the risk of exposure of people from pets that get infected from feral dogs.
- Widespread vaccination of feral dogs, to reduce exposure of people and pet dogs. Achieving high vaccination rates (>70%) in the feral population is a critical control measure, but can be very challenging.
- Education of people about dog bite prevention.
- Education of people about dog bite care, particularly ensuring that they seek post-exposure treatment if bitten by a feral dog or a dog of unknown rabies status that can't be quarantined for 10 days to ensure it's not rabid.
- Education of healthcare personnel so that everyone who needs post-exposure treatment gets it (and gets it done right).
- Education of public health personnel to ensure that the two points above get done right.
- Ensuring adequate supply of good quality rabies vaccine and antibody for post-exposure treatment.
Yes, these measures require more work than a cull, and to some degree they also require a culture shift in the approach to keeping pets, but if China really wants to start preventing the thousands of rabies deaths that occur annually, that's what needs to be done.
A 73-year-old New Jersey woman has died of rabies after being bitten by an infected dog. The woman was visiting Haiti in April when she was bitten, and she developed signs of neurological disease in late June. Family members and healthcare workers are being assessed to determine whether they may have been exposed to rabies during care of the woman. If so, post-exposure treatment would be started.
Rabies is a devastating but almost 100% preventable disease. While rare in most developed countries, canine rabies is a huge problem internationally and kills tens of thousands of people every year. The main reason it kills so many people is because of inadequate access to proper post-exposure treatment or failure to seek medical care. Timely access to post-exposure care can virtually guarantee that a person won't get rabies.
Why this woman didn't get post-exposure prophylaxis (I'm making the assumption that she didn't) isn't reported, and it could be because of patient or healthcare factors such as:
- Assuming a minor bite isn't a big deal.
- Not thinking about the potential for rabies.
- No access to adequate heatlhcare.
- The physician not thinking about rabies.
- Inadequate or no supply of rabies vaccine (for post-exposure treatment).
All of these problems can occur. Education of the public and medical personnel, as well as ensuring adequate access to rabies vaccine, are critical to prevention.
More information about rabies can be found in the Worms & Germs Resources page.
A Chapel Hill, North Carolina woman is suing Orange County in response to quarantine of her dog because of possible rabies exposure. This lawsuit highlights some of the inconsistencies in application of current rules, along with some misunderstandings.
In February, her dog Russell was barking at something under her deck, and that something ended up being a raccoon with rabies. There's no evidence of a fight or contact, but it can't be ruled out. Because of this, the dog was considered potentially exposed. Russell was overdue for his rabies booster, so a strict six-month quarantine was required, and the county required that this be done at an approved facility, not in the home. (The alternative option was euthanasia.)
- The lawsuit is based on the inconsistent application of the rules by various counties. The owner is seeking permission to quarantine the dog at home. This is allowed in many regions, provided there is confidence that the owner is responsible enough to properly quarantine the animal.
- It's a reasonable argument that's based on subjective and variable application of rabies guidelines. Certainly, formal quarantine in a facility offers more containment. The question is when household quarantine is appropriate, in terms of the animal's risk of exposure and the ability of the household to properly quarantine the animal.
Some other highlights:
Russell was overdue for his rabies vaccine by 46 days.
- Dogs don't immediately go from protected to unprotected. Certainly, we want animals to be up-to-date on their vaccines, but some thought needs to go into dealing with potentially exposed overdue animals. The NASPHV Rabies Compendium states "Animals overdue for a booster vaccination need to be evaluated on a case-by-case basis (e.g. severity of exposure, time elapsed since last vaccination, number of prior vaccinations, current health status, local rabies epidemiology)."
- Knowing the age of the dog and the number of previous vaccines would help, but the news article reports vaccinations (plural), suggesting that he's been vaccinated more than once in the past. In a dog with a relatively low index of exposure that was only overdue by 46 days, it would seem reasonable to consider it protected and treat it as vaccinated (although it's hard to say this definitively based on a news report that doesn't give the whole story). It's a critical point because considering the dog up-to-date would only result in a 45 day observation period as opposed to a strict six-month quarantine.
The owner's veterinarian stated that research shows that an animal that is vaccinated regularly is protected for many years, if not a lifetime.
- Yes and no. Vaccination is quite effective and in most animals probably confers long-lasting protection. However, I'm not aware of research that really shows this. This isn't a disease where we have good research data about duration of effect of vaccination. I suspect that most dogs that have been regularly vaccinated are well protected. Most does not equal all, and with a disease like rabies, you have to be quite sure.
A rabies antibody titre was measured. This is a blood test indicating the level of anti-rabies antibodies. The veterinarian indicated that the titre showed Russell is currently protected from contracting rabies.
- Unfortunately, no. TItres tell you antibody levels, but we don't have good data about what is actually protective. Higher is better, but we can't say a certain number is absolutely protective. Back to the NASPHV guidelines: "Titers do not directly correlate with protection because other immunologic factors also play a role in preventing rabies, and our abilities to measure and interpret those other factors are not well developed. Therefore, evidence of circulating rabies virus antibodies should not be used as a substitute for current vaccination in managing rabies exposures or determining the need for booster vaccinations in animals". That statement was echoed by North Carolina's state public health veterinarian, Dr. Carl WIlliams.
This is a tough situation. In many circumstances, home quarantine is a reasonable option. It's easier on everyone involved, by not separating the dog from the household. It's also less expensive. However, it inherently comes with some degree of risk to the household and the community. It's only a reasonable option when it's certain that people will take "strict quarantine" seriously, and truly quarantine the animal. That's hard to assess, and regulatory bodies are presumably afraid of assuming liability should they allow someone to quarantine an animal at home and something bad happens (e.g. it develops rabies and exposes people in the household, the owners take it outside where it encounters other animals or people, it escapes...). Determining whether someone can and will properly quarantine an animal isn't easy, and those issues presumably lead some people to err on the side of caution, and require formal quarantine at an approved facility.
The easiest way to avoid all this: Ensure your pets are properly vaccinated.
A report from India of apparent failure of rabies post-exposure prophylaxis raises a significant concern. Few details are available, but it is reported that the affected person is currently in a coma, and if that is the case, death is almost certain. This case requires careful investigation, given the almost invariably fatal nature of rabies and the assumption that proper post-exposure treatment is basically 100% effective.
From my standpoint, I'd want to confirm that:
- the person actually completed the proper treatment course (one dose of anti-rabies antibodies and a series of four rabies vaccinations over a few weeks) - the article says the course was completed but doesn't give details of what that entailed.
- proper antibody and vaccine were used.
- correct doses were administered.
- the antibody and vaccines had been handled properly (e.g. kept at required temperatures - which at times may be easier said than done in a country as hot as India).
If all of these factors are confirmed, I'd want to know whether the person had some other disease or a compromised immune system that might have prevented him/her from responding properly to vaccination.
If no underlying problem was present, I'd want to see some testing of the lots of antibody and vaccine that were administered to ensure that they were adequate.
The timeline from when the person was exposed to when he/she received the post-exposure treatment to when he/she developed clinical signs of rabies is also critical. Delaying treatment for too long can also result in treatment failure.
Undertaking such an investigation is very important because the cause for any treatment failure needs to be understood if at all possible to help prevent it from happening again.
In the same news article, another man is also reported to be in a coma due to rabies infection, because he failed to complete the full course of treatment. That's a more common problem and can be caused by lack of awareness of the importance of completing the full treatment course, inadequate communication with healthcare providers and, in some regions, shortage of vaccine.
These cases show that while post-exposure treatment is a critical aspect of rabies prevention, it shouldn't be relied on as the sole line of defense. Feral dog control, rabies vaccination of animals and education regarding bite avoidance are critical rabies-control measures that often get ignored.
A few more details are available about the apparent case of a person surviving rabies infection that I also wrote about in a post a few days ago. The affected individual is an eight-year-old girl from Willow Creek, California. She initially had non-specific signs of illness (which is not unusual for rabies) and at her first visit to a doctor, it was thought that she probably had the flu. However, her illness progressed quickly and she developed severe neurological signs shortly thereafter. She was sent to the University of California Davis Medical Center, where she was diagnosed with rabies a week later. I'm not sure if they suspected rabies before the diagnosis and started treatment, or whether they didn't initiate treatment until after the diagnosis was made. Presumably, they started treated based on a suspicion of rabies because she would have deteriorated greatly during that week otherwise.
Her current health status isn't reported so it's not clear whether she is truly out of the woods or whether there are any residual neurological abnormalities. If treatment is successful, this girl would be only the fifth person (as far as my count goes) known to have survived rabies infection. Presumably she was treated with a form of the Milwaukee protocol, which involves putting the patient in a medically-induced coma and administering a series of anti-rabies drugs. When it was first reported to be successful, this protocol was hailed as a remarkable breakthrough in the management of rabies (which is was). However, it still has a low success rate, which is a testament to the severity of rabies and the often late recognition and initiation of treatment. Hopefully more details about the treatment protocol and her clinical status will be made available soon.
On a happy related note, Jeanna Giese, the girl who in 2004 became the first known rabies survivor in the world, graduated from College a few weeks ago at the age of 21.
Although limited on information, there's a recent report of a person with rabies in California, with some hope for survival. Rabies was apparently diagnosed in the person on May 6. Incredibly, not only is the woman alive, but she is reported to be in "stable condition" and improving at UC Davis Medical Center. That's remarkable because rabies is almost always fatal, and death usually occurs fairly quickly by the time rabies is suspected and diagnosed. Rabies survival has been reported but is extremely rare.
While it's far too early to talk about survival and cure of the woman's illness, there are many different factors that could be involved in this potentially successful treatment. These include very rapid administration of anti-rabies treatment, use of the "Milwaukee protocol" (which was the first successful treatment protocol for rabies in a person, which has also failed to be successful numerous times since), pre-existing partial immunity from previous vaccination, and/or the whims of biology and the immune system. Hopefully, this person will continue to improve and more information will be made available about why treatment has been successful so far.
The source of rabies is suspected to have been feral cats, although this is far from certain and it may be that this presumption is based on the lack of other more likely possibilities. While this is an encouraging report, it doesn't change the fact that rabies almost always kills, and it's almost 100% preventable with proper post-exposure treatment. People need to be aware of how to avoid rabies and that prompt treatment is needed anytime rabies might have been encountered.
Rabies in a lamb and cow at a petting zoo (or more accurately, in a communal group of hobby animals) has been reported in Israel. This follows identification of rabies in another lamb from the same group last week. Little is reported about possible sources of infection of these animals, at Kibbutz Neve Eitan, or how widespread human exposure may have been. It's a concern given the serious nature of rabies and the possibility that there was largely uncontrolled contact with the public, which complicates tracing of potential exposures. Given the state of rabies in Israel, the canine rabies variant is most likely the cause.
Presumably, public health and Kibbutz personnel are contacting people in the area to determine who may have had contact with the animals. Casual contact is not a risk for rabies transmission - it is only transmitted through contact of an open wound or mucous membrane (e.g. nose, mouth, eyes) with saliva from an infected animal. The risk of transmission to humans from contact with species like sheep and cattle is pretty low, however the tendency of young animals to suck on things and the fact that people often let them suck on a fingers when playing with them raises the potential for exposure. Anyone identified as having high-risk contact needs post-exposure treatment, consisting of a shot of anti-rabies antibodies and a series of four vaccines over the course of a month (unless they have been previously vaccinated against rabies, in which case they just need two booster shots).
Any animals involved in public displays, petting zoos or other events where there may be contact with the public should be vaccinated against rabies. That's particularly true in areas such as Israel, where rabies is endemic.
The latest edition of CDC's Morbidity and Mortality Weekly Reports describes a case of rabies in a Michigan man from 2009. While human rabies in most developed countries is very rare, this is yet another reminder of the ever-present risk of rabies exposure in many regions, and the ongoing need to be proactive to avoid this almost invariably fatal - but almost completely preventable - disease.
In the 2009 Michigan case, the man woke one day with a bat on his arm. Bats are classic rabies vectors, and you have to assume that any bat has rabies until proven otherwise. If you can't be sure that you weren't bitten or scratched (something that may be easier said than done, because bats bites can be very tiny), then you have to consider yourself exposed if you've had contact with a bat and the bat wasn't tested and rabies-negative.
Unfortunately, the Michigan man did not seek medical attention, and nine months later he started to develop signs of rabies. It started off with pain and progressive numbness in his left hand and arm, and pain in his neck and back. He developed weakness in his left hand and soon could not grip anything or raise it more than a few inches.
While he was being evaluated in hospital, he developed breathing difficulties and had to be placed on a ventilator. Various diseases were considered and numerous tests were run. After a little initial improvement, he began to deteriorate, with more profound neurological signs.
Five days after he was admitted to hospital, his wife was asked about possible animal bites, but she didn't know of any. A couple of days later, a relative recounted being told about the bat encounter, but there was little that could be done at that point, and the man died three days later. Rabies was eventually diagnosed.
Because of the potential risk of exposure, 11 family members that may have had contact with the man's saliva received post-exposure treatment.
Sadly, you can almost guarantee that rabies could have been prevented if he had reported the bite and received post-exposure treatment (even months later). Rabies education is critical so that people know the risks of exposure and know to get medical advice after any encounter with a wild animal.
- Like all mammals, donkeys are susceptible to rabies virus but infections are not particularly common. Raccoon rabies has also be identified in the area, and a bite from a raccoon may have been the source.
- A York County woman was bitten by a kitten that ran into her house when the door was opened for someone else. The kitten bit her when she grabbed it to throw it (hopefully not violently) back outside... an understandable reaction but not what you want to do in a case like this. You need to know whether a wild animal that bites is rabid, and if it gets away, you can't test it. You need to get away from it but keep it contained until someone can come get it. The other problem with people getting rid of the animal is that they might not recognize the risk of rabies. In this case, the kitten was hit by a car after being removed from the house, which allowed for it to be tested.
Yet another report of a dog being exposed to rabies through contact with wildlife, then being euthanized because it was not properly vaccinated.
- An unvaccinated animal that has been exposed to a rabid animal has to be euthanized or undergo a strict six-month quarantine. A vaccinated animal only needs a 45-day observation at home.
- Encountering a manic bobcat isn't something I'd like to do, and a LaCrosse, Florida woman spent nine days in hospital after being attacked by one. The 25-pound cat was trying to get the family's cat, then lunged at the woman when she came outside the house, aiming for her neck. Her husband then shot it. They knew that the bobcat needed to be examined, and took the rather unusual approach of bringing it to the hospital emergency room with them (I'd love to have seen that). I don't imagine hospital personnel did anything, but Florida Fish and Wildlife Conservation Commission personnel came and got it, and later confirmed that it was rabid. (Image: Lynx rufus, US Fish & Wildlife Service)
Raccoons are fascinating critters but they don't make good pets. Their curiosity makes them quite disruptive and damaging, and they have seriously injured people (particularly infants). They are also rabies vectors, and in many regions raccoon ownership (along with other wildlife species) is illegal (or only legal with a license). Despite all this, some people continue to keep raccoons as pets, and injuries continue to happen. Unfortunately, it's often not the owners that suffer the consequences, but children.
A one-week-old Griggville, Illinois baby is in hospital after being attacked by her grandparents' pet raccoon. The baby was in a room with the raccoon (not a good idea to start with), when the raccoon starting biting and scratching the baby's face and head. The raccoon's owner thinks the raccoon wasn't being vicious, just curious and trying to get a ribbon off of the baby.
"Rampy was trying to get the bow off the baby's head and it's got long claws and he was scratching up the head trying to get the bow off," said the owner.
Regardless, the fact that it caused severe injury indicates it's a hazard. (Wounds caused by accidents heal at the same rates as those caused my malice.)
Euthanasia of the raccoon was requested to test it for rabies. The owner countered that it had been vaccinated against rabies and dewormed (which raises the question of what veterinarian did this. I'd consider vaccinating and deworming an illegal pet unethical at best). Further, rabies vaccination does not guarantee that the raccoon isn't rabid. A judge eventually ordered the raccoon to be euthanized.
You'd think the raccoon's owners would be aghast at the attack. While I can see how they'd be attached to their pet, typically concern over a grandchild takes precedence. Not here, however, as the owners fought the euthanasia order and are railing against local authorities for having the raccoon euthanized after a potentially life-threatening attack. Even the infant's father is taken back by their attitude, stating "If it was somebody's dog that bit a kid, they'd be held accountable. These people should be held accountable for [the raccoon]."
In Canada, rabies testing and surveillance is performed by the Canadian Food Inspection Agency (CFIA). National data for 2010 are now available and indicate there were a small number of cases in domestic animals, with more in wildlife, for a total of 123 cases.
Dogs: There were three cases, all in Saskatchewan.
Cats: Four cases, three in Manitoba and one in Alberta.
Horses: One rabid horse in Manitoba.
Cattle: One, from Manitoba.
Skunks: 60 cases, 33 in Manitoba, 17 in Saskatchewan and 10 in Ontario.
Bats: 48 rabid bats, most in Ontario (29) but also in BC, Alberta, Saskatchewan, Manitoba, Quebec, New Brunswick and Nova Scotia.
Foxes: Six from the Northwest Territories or Nunavut.
No rabid sheep, goats, raccoons (down from 58 in 2007), wolves or other species.
Manitoba seems to win the 2010 rabies prize, while Newfoundland and Labrador, Prince Edward Island and the Yukon had no cases.
As with any disease surveillance, these numbers underestimate the scope of rabies. For an animal to appear on the list, rabies had to be considered and testing performed. So, for wildlife, it's a massive underestimation of the number of cases, since most affected wildlife don't get tested. Wildlife testing (and testing in general) is typically only done when there has been the potential for human exposure. Domestic animal cases are probably a fairly close representation of the status of rabies in pet and farm animals, since it's reasonably likely that a domestic animal with rabies would be identified as such and tested (although certainly cases can be missed or neglected). As with wildlife, there is probably an under-identification of rabies in feral/stray dogs and cats, since testing would only be done on these animals if they are caught and if there was potential human exposure.
- No? Maybe only if you're a high school wrestler from North Dakota.
On the way to the finals of a tournament, a busload of wrestlers came across a "dead" raccoon. For reasons that are unclear, they thought it would be a good idea to pick up the raccoon carcass and take it with them. They put it in the storage area of their bus and continued on their way.
Not only did that group of students display some questionable judgment by picking up the carcass, they also failed to notice that their "dead" raccoon was not actually dead. When they arrived at the tournament, the raccoon got up and ran away.
So, not particularly bright (or observant), but maybe not that big of a deal. Raccoons are important rabies vectors and a raccoon that allows itself to be loaded onto a bus by a bunch of high school students, and then later runs away, must be considered potentially rabid since you can't prove otherwise. However, you don't get exposed to rabies just by riding in the same bus as a napping raccoon. You have to have close contact with it (e.g. bite that breaks the skin, exposure of an open scratch/wound or mucous membrane (nose, mouth, eyes) to raccoon saliva).
In this case, however, the team was removed from the tournament when officials found out "they had been in contact with the wild animal and feared they may have contracted rabies." This makes no sense.
- If they were exposed, they'd pose no risk to anyone else at that point. You don't become immediately infectious after exposure. These students could not have transmitted the virus to other competitors.
- There was no evidence that they were actually exposed. No one was bitten or scratched.
Carrington school superintendent Brian Duchscherer said: "Once we found out, we didn't know if there was a potential of spreading anything or if the raccoon had rabies or not but we decided to bring our kids home." I would hope that a quick call to public health would have put those concerns to rest. Either they didn't bother to try to get good information or they got bad advice.
The situation occurred in March 2010, when a stray dog taken to a North Dakota animal shelter was diagnosed with rabies. An investigation was undertaken to look into human and animal exposure.
- Potential exposure was investigated in 32 people. Of these, 21 were determined to fit criteria for requiring post-exposure prophylaxis. This included nine shelter employees and one volunteer.
- Twenty-five dogs at the shelter were considered exposed. According to the report "In accordance with 2009 Compendium of Animal Rabies Prevention and Control guidance (1), the 25 dogs in the shelter with the rabid dog were euthanized." That's a somewhat misleading statement. Immediate euthanasia is not the only recommendation in this kind of situation, it's just one of the options. In a dog that has not been vaccinated (or whose vaccination status is unknown), euthanasia OR six months of strict quarantine is indicated. The decision to euthanize was probably a logistical one, not being able or wanting to quarantine this many dogs for such a long period of time. It's a reasonable decision given limited isolation capacity (and budget).
- Twenty-five other unvaccinated dogs that were adopted or claimed by their owners were also exposed. (Presumably, these were dogs that had contact with the infected dog, then went to homes before the rabid dog was diagnosed). Of these, 11 were euthanized, 13 were quarantined for 6 months at home, and one was 'unintentionally killed' (whatever that means). All euthanized dogs were tested and were negative for rabies.
A few issues were raised in the report:
Rabies vaccination of shelter personnel: "In addition, preexposure prophylaxis for animal shelter workers or other persons whose activities bring them into frequent contact with potentially infected animals should be considered, in accordance with Advisory Committee on Immunization Practices recommendations (6)" This is a complex issue. It would be ideal for all shelter employees to be vaccinated, and I'd love to see that done. The problem is actually getting it done. Shelters often have many employees and volunteers, and a very transient worker population. Getting all these people vaccinated is tough. Vaccinating short term, part time and temporary employees is tough enough, let alone volunteers. Cost is also an issue. Is it realistic to make people volunteering or earning low wages to pay the expensive cost of vaccination? Can shelters afford to pay for vaccination? What happens if someone doesn't want to be vaccinated? This is an ongoing issue in shelter medicine and one where there is no clear consensus. Shelter personnel clearly fit standard recommendations as being a group in which vaccination should be considered, but it's easier said than done.
Vaccination of animals: "First, all domestic animals should be vaccinated against rabies, in accordance with guidelines (1,8)." This is another issue that is very good in principle but tougher in practice. Rabies vaccination must be done by a veterinarian in most regions, and most shelters do not have a resident veterinarian. Getting animals vaccinated promptly after admission can be difficult. Ideally, shelters would have better and closer relationships with veterinarians, but it's quite variable (and an area that needs improvement). Vaccination would also not help much in some situations, since it does not result in immediate protection. Dogs that are vaccinated are not considered protected for 28 days. Therefore, even if they were vaccinated at arrival, some of the dogs in this situation would still be considered unprotected. Nonetheless, I don't want to dismiss the role of vaccination, and I think shelters need to significantly increase rabies vaccination rates. It's not a simple problem, however.
Contact in the shelter: "Second, animals without documentation of vaccination against rabies should be kept separate from the public, wildlife, and other animals to prevent transmission of the virus (5,8)." Another "good in principle, but have you ever been to a shelter?" statement. Shelters don't have lots of space. Having enough room to properly separate incoming, sick, and adoption animals is hard enough. Having to separate all those groups into rabies-vaccinated and non-vaccinated, or individually isolate animals, is going to be impossible logistically in most facilities. The concept of cohorting animals of different risks is excellent and can be improved on, it's just not possible to isolate all animals that are unvaccinated or of unknown vaccination status (i.e. almost every animal coming into a shelter). This is particularly true since they are not considered protected until 28 days after vaccination.
Infection control practices: "In this case, 36 dogs had to be euthanized because employees and volunteers might not have consistently followed the shelter's policy of preventing muzzle-to-muzzle contact between dogs." Compliance with infection control practices is an issue, and it could be improved. It's an area we're working on now.
Definition of contact: In this particular situation, a very broad definition of contact (that may result in exposure) was used. "Although the shelter's animal handling policies likely minimized contact among dogs, muzzle-to-muzzle contact could not be ruled out; therefore, BOAH and NDDoH recommended that all dogs present in the shelter from March 9--20 be euthanized." It's quite unlikely that any of these other dogs were truly exposed if this is the only kind of contact they may have had with the rabid dog. Balancing public health and animal welfare is difficult. Certainly, you need to err on the side of caution, but how far do you go? Quarantine would have been ideal because of the extremely low likelihood of exposure, however if it's not practical (or feasible or affordable) in a shelter situation, euthanasia may be the only option.
This was a bad situation but it's not surprising, nor will it be the last time it happens. A single rabid dog led to the euthanasia of 36 other dogs, and expensive (and probably stressful) treatment of 21 people. Shelter management can be improved to reduce the risk of this happening, but there's no way to absolutely prevent it.
A recent news report from Berkshire, Massachusetts that was highlighted by ProMed is a strange and concerning story of rabies exposure.
The story involves two people that were stalked and attacked by an aggressive fox. One man was attacked in his driveway. He fought the fox off with a smoker lid, but several hours later it attacked and attached itself to a woman next door who was outside collecting her recycling bin. The fox bit her multiple times, and it took 20 minutes (with the aid of the same smoker lid - apparently a good fox extractor) to remove the fox from the woman’s leg. The man then killed the fox.
The woman’s sister called the police, who dispatched paramedics and suggested they call Animal Control to get the fox tested for rabies.
So far, so good. Unfortunate attack but managed as well as can be expected.
Anyway, when the paramedics arrived, they told the woman that she didn’t need to go to the hospital. A little more information in the article would have been nice here. Based on the severity of the injury, the response of the paramedics probably makes sense. The fox had bitten her, but the bites didn’t appear to be too serious from a trauma standpoint, and racing her off to the hospital in an ambulance was not required. However, rabies exposure is a major concern and this scenario raises a good question: What is the role of paramedics in thinking about and educating people about the risk of rabies exposure? Ideally, paramedics should know enough to tell people that they should seek medical care when there has been potential exposure to rabies. I don’t know whether this is the case, however. If someone isn’t injured enough to require emergency care, is that all that the paramedic needs to assess?
The woman then had a relative drive her to the emergency room. If this was because of concerns about the severity of bites, then that makes sense. If it’s from a rabies exposure standpoint, then it’s overkill. Assessment of rabies exposure and starting treatment is considered a medical "urgency," but not an "emergency." Basically, that means you don’t need to be treated immediately and you have time to go to a regular physician. In this case, going to her physician the next day would have made the most sense, since emergency rooms are not the ideal place for rabies assessment and exposure treatment.
The fox was rabid in the end, and the woman was started on rabies post-exposure treatment. Even if this was an inefficient way of getting care, the key point is that she was treated. Rabies is almost invariably fatal but is almost 100% preventable with proper post-bite care.
The description of her treatment is strange, however. “On Monday she began the lengthy series of anti-rabies vaccinations, which included injections into each bite mark. She returned to the hospital for another shot on Thursday and learned that she has 10 more vaccinations to endure this month, with each hospital visit at a USD 75 co-pay.” This makes no sense. Current-day rabies post-exposure treatment consists of a series of 4 doses, not 10 or more.
Another strange part of this story is the apparent difficulty the two victims had getting the animal tested. The people who were attacked claim “I called a rabies hotline and nobody picked up." As a result, the fox's body sat on the woman's property for three days until they took it to a local vet clinic, that shipped the fox’s body for testing. In another strange twist, it seems the woman had to pay for testing herself. That makes absolutely no sense. This is clearly an animal with a high likelihood of having rabies and a situation where there has been clear exposure of a person. The rabies status of the animal must be determined and requiring people to pay for that themselves makes no sense.
By the time I posted this story, the Berkshire newspaper had pulled the article from its website. I don’t know why. It could because the story was poorly written or the information was incorrect. Regardless, it raises some interesting issues.
A Royal Oak, Michigan resident is undergoing rabies post-exposure prophylaxis after being bitten by a rabid cat. The person found a sick cat by the side of the road and took it to a vet clinic... a good deed in theory, but problematic in many ways. One obvious risk is the potential for rabies exposure, as occurred here. The cat was subsequently diagnosed as rabid, and having been bitten the good samaritan was clearly exposed. Fortunately, the veterinarian kept the contact information for the person who dropped off the cat, who can therefore now receive the necessary treatment.
Associated with this event, the Royal Oak Animal Shelter has issued the following reminder:
- Do not approach any animal if it appears sick. Call the Police to get animal control involved.
- Tell your children to stay away from any stray animals, whether they are skunks, dogs, or cats. Any of these could be infected.
- Vaccinate your dogs for rabies. It is the law.
- If you let your cats outside, STOP doing so. If you can't stop, please make sure your cats are vaccinated for rabies.
- If they already have been vaccinated, talk to your veterinary professional about having a booster administered to protect your animal. There is no cure for this deadly disease.
Many people think of rabies as a very rare disease primarily associated with wildlife, however canine rabies kills tens of thousand of people each year, making it a leading cause of infectious disease deaths in some areas. China is an example of such a region, and rabies is a serious problem throughout much of the country. For example, last month 33 people died of rabies in Guangdong province, according to the the Provincial Health Bureau. That means that there were more deaths from rabies than tuberculosis in the region (there were 80 deaths from AIDS, 33 from rabies and 14 from TB).
The frustrating part is that the vast majority of rabies infections can be prevented with basic medical care, consisting of timely administration of rabies post-exposure prophylaxis, and vaccination of both feral and pet dogs.
A recent paper about rabies post-exposure treatment in animals (Wilson et al, J Am Vet Med Assoc 2010) also contained some interesting information about rabies vaccine failure in pets. The study, which looked at data from more than 1000 animals in Texas from 2000-2009, mentioned a vaccinated 15-month-old cat that developed rabies. It had been vaccinated at 5 months of age and was not yet due for a booster, which would have been required at 17 months of age.
Rabies was also diagnosed in a dog and cat that had been vaccinated but were overdue for their boosters. Both initially received one dose of a 3-year vaccine, but they did not received the booster that is supposed to be given 1 year later. (Even with 3-year vaccines, pets are supposed to be given their first booster (i.e. their second dose of vaccine) after 1 year, before moving to getting boosters every 3 years). The dog was vaccinated 2 years and 9 months earlier. Twelve days after being exposed to a rabid skunk it was given a booster, but it developed rabies nonetheless and died 8 days later. The cat was vaccinated 2 years and 3 months earlier. It apparently did not receive a booster after it was exposed to rabies, and subsequently also died of rabies.
Another six dogs and three cats that were vaccinated developed rabies, but all of these were overdue for their booster or had been vaccinated less than 30 days before rabies exposure. These were therefore not considered vaccine failures.
This information should not be taken as an indication that rabies vaccination is not useful or that current vaccination protocols are inadequate. This involves a very small number of animals, and only one that was properly vaccinated. Rather, it should be a reminder that vaccination is not infallible and that the possibility of rabies cannot be summarily dismissed just because the animal has been properly vaccinated.
If an unvaccinated dog is exposed to rabies, the typical requirement is a strict six-month quarantine (with rabies vaccination one month into quarantine or one month before the end of quarantine) or prompt euthanasia.
Why? There has been only limited investigation of rabies post-exposure treatments in dogs. Ineffective post-exposure treatment could put the people around an exposed dog at risk of rabies exposure themselves. In the absence of convincing evidence, public health concerns trump animal issues.
A recent study published in the Journal of the American Veterinary Medical Association (Wilson et al 2010) sheds some more light on the topic. The authors reviewed records from rabies-exposed animals in Texas from 2000-2009, where a different post-exposure protocol is used for animals. In Texas, exposed unvaccinated animals are either:
- immediately euthanized, OR
- immediately vaccinated, kept in strict isolation for 90 days and given rabies vaccine boosters during the 3rd and 8th week of quarantine.
The authors reviewed the records of 1014 animals (769 dogs, 126 cats, 72 horses, 39 cattle, 3 sheep, 4 goats and 1 llama) that were treated with this modified protocol after exposure to another animal that was confirmed to be rabid.
None of the treated animals developed rabies.
An important issue to bear in mind is whether the animals in the report were actually exposed to the rabies virus itself, not just a rabid animal. There's no way to prove that any were actually exposed to the virus, however 29% had what was considered "direct exposure," and a further 38% had "probable exposure." Presumably, not all the animals were actually exposed, but even so, because they looked at so many animals, it provides more convincing evidence that the protocol is effective for preventing rabies. The only definitive way to figure it out would be to experimentally infect animals with rabies and then see if the post-exposure treatment prevents them from developing disease, something that is unlikely to be done for many reasons.
Immediate vaccination may be a key component of this protocol. Previous reports of post-exposure treatment failure have been cases where there was a relatively long interval (e.g. a couple of weeks) from rabies exposure to first vaccination. By that time, it's possible that the infection is too advanced, particularly since the typical incubation period for rabies in dogs is 21-60 days.
The Texas post-exposure protocol makes sense. It appears to be effective and requires a shorter quarantine period. Those are both important factors, and make post-exposure treatment a more viable option.
However, while this study provides evidence that this protocol may be effective, it doesn't mean everyone can just start using it. Regional laws regarding rabies exposure supercede these results, and unless the rules are changed, this approach may not be an option. Hopefully, regulatory officials will look at the results of this study and Texas' experience, and think about modifying their own protocols.
At the end of the day, however, it's still much better to have your animal properly vaccinated against rabies so that post-exposure treatment or quarantine isn't needed. Vaccination isn't 100% effective, but it's very good overall, and the mandated response to exposure of a vaccinated animal is much easier (on both the animal and owner) than for an unvaccinated animal.
A dead otter was found floating in a pond in Florida near the site of a recent otter attack that was captured on video. Testing confirmed that the animal was rabid. It's impossible to determine whether this is the same otter that attacked the teenager in Boca Raton last week, but it's likely, and shows that rabies post-exposure treatment of the victim was a good decision.
Numerous rabid otters have been identified in Florida in recent years. I haven't seen any information about the viral types that have been involved or how it is thought that otters are becoming infected. Regardless, these incidents should be a reminder to stay away from wildlife, and to consider rabies exposure any time someone has been bitten by a wild mammal.
A teenager who was filming an otter he spied in a pond now knows more about rabies than he probably ever wanted. The 19-year-old shot the video from the bank of a pond, watching the otter innocently swimming around. After a brief stare-down, the otter did another quick swim, then ran onto shore and attacked! And it was all caught on camera and displayed to the world via YouTube.
This is the third recently-reported otter attack in the area. This type of behaviour obviously isn't normal, and rabies has to be a concern. Rabies has been previously identified in marauding otters in Florida, and since this otter got away, you have to assume that it was rabid. Accordingly, the victim is undergoing rabies post-exposure treatment.
Humane societies and shelters are often overwhelmed by the number of animals that come in. It's pretty uncommon to see much (if any) empty space in most shelters, and overcapacity shelters lead to increased risk of disease transmission, outbreaks and suboptimal care of the animals that are there.
One way of helping deal with overcrowding is fostering animals to people's homes for periods of time. Typically, foster homes take animals when shelters are at capacity, or take specific animals such as nursing cats, which are more difficult to care for properly in a shelter.
Most places have protocols for fostering, but they're not always very comprehensive and they don't always adequately cover some important areas. If you are thinking about fostering shelter animals, you need to think about the risks and whether you can manage them.
Are there people in the household that are at increased risk of infection?
Fostered animals should be assumed to be at higher risk of carrying and transmitting various infectious diseases. They can have high rates of carriage of various intestinal bacteria and parasites, along with a host of other microorganisms (e.g. ringworm). They may also be more likely to bite and scratch, not necessarily because they are aggressive, but often because they are young animals that may do so when playing. They may also be more likely to poop in the house.
Households with children under the age of 5, elderly individuals, pregnant women or people whose immune systems are compromised are at increased risk of various infections, both in terms of the likelihood of becoming infected and the likelihood of developing more severe disease. Households with these types of individuals should not foster animals. They are much better off having their own lower-risk pets.
Are there any "resident" pets in the household?
You might expect that someone willing to foster animals would also have their own pets, but that's not always the case. Non-pet owners are actually ideal, since this negates any risk of diseases being spread from or to household pets that live there long-term. However, it's more typical that foster homes also have such resident pets.
Are there any pets in the household that are at higher risk for infection?
As with people, there are some animals that are at increased risk of infection. These include the very young, very old, pregnant and pets with compromised immune systems. The latter group would include pets with chronic illnesses, those being treated with high doses of steroids for various diseases, animals with cancer, animals with diabetes, and a range of other issues. People owning a pet that fits into one of these categories should not foster animals because of the risk to their own pet.
How do you reduce the risks associated with fostering animals?
- May sure there are no high risk people or pets in the household.
- Make sure the shelter or organization knows what they are doing. Make sure they have a clear protocol that says who will be fostered and how it's done.
- Look at the animal before you get it. Visit it at the shelter. See if it looks healthy. If you have any questions, make sure it's examined by a vet before it reaches your home.
- Use good hygiene. Wash your hands regularly. Properly clean up feces and clean litterboxes regularly.
If you have pets of your own:
- Make sure they are vaccinated and on an appropriate parasite control program.
- Keep the new animal away from your pet at the start. That lets you find out more about the animal, and it gives you more time to see if there are potential infectious disease concerns.
- Do a controlled introduction of the new animal. Slow, supervised introduction of the animals can reduce the risk of bites or scratches.
Fostering is a good way to reduce pressures on humane societies and shelters, and to provide better care for some animals, like pregnant animals or those with young kittens/puppies. A good fostering program can be set up with limited risk to all involved, but infectious disease risks can never be completely eliminated. By accepting a new animal into your house, you increase the risk of exposing yourself and anyone else (human or animal) to infectious diseases. That's just a fact of life.
A nine-month old Georgia (US) baby is in critical condition after being attacked by two raccoons while sleeping in her crib. The attack occurred in the middle of the night, and the baby ended up with severe bites over her head and other parts of her body.
It's not clear at this point whether these were pet raccoons that were being kept illegally or whether two raccoons broke into the house. If the latter, it's suspected that the family may have been feeding the raccoons, which could have made them less fearful of people than usual. The news clip also shows a large cage outside that could presumably house raccoons (pure speculation on my part here). Authorities are investigating whether these were illegal pets, and if so charges could result.
An unprovoked raccoon attack in a house is pretty strange. Raccoon attacks would be more likely in the raccoon's environment or if they were sick (e.g. rabies). They might also be more likely to try to break into a house if they have been fed by people and lost their fear of humans. Still, attacking a baby seems like a very strange thing for them to do. I also wonder whether an attack like this might be more likely with a pet raccoon, especially if it was an older, established raccoon in a household where a new baby had disrupted the routine.
Rabies has to be a major concern in a situation like this. One of the raccoons was killed by police. The news clip and article on the same website provide conflicting information about whether the other raccoon was caught. Both raccoons need to be tested to determine whether they had rabies. Otherwise, the baby will need rabies post-exposure treatment.
I recently had a rabies exposure and treatment question that's worth discussing. It was from a person in India whose young child had potentially been exposed to rabies. The child had a wound on her hand and a stray dog licked the area. It wasn't reported to the parents until a little while later. Three doses of rabies vaccine were obtained and the vaccine series was started a few days after the potential exposure.
Here are some issues:
- Was this child actually exposed? It's hard to say. It's probably unlikely that rabies virus was inoculated into the child in a situation like this, with relatively minor skin lesions and fairly brief contact with the dog. However, contact of saliva from an infected animal with broken skin is a potential route of infection so, even if it's unlikely, you have to err on the side of caution and consider the child exposed.
- Standard recommendations for post-exposure prophylaxis are 4 doses of vaccine on days 0, 3, 7 and 14. Three doses might be effective but it's hard to have confidence in it, especially when dealing with an almost invariably fatal disease. Trying to get ahold of a 4th dose would be best in a situation like this.
- It doesn't appear that rabies antibody was administered at the start. Standard protocol is to give anti-rabies antibody with the first vaccine dose. This provides an antibody boost and early protection while the vaccine is taking effect. The antibody can still be used even if it wasn't given with the first dose of vaccine, as long as it's within the first week. After that, it's assumed to have limited effect because antibodies from vaccination would be increasing. It's probably more important with serious bites and bites near the head and neck, where the onset of rabies can be earlier, but getting a dose of antibodies within the first 7 days would still be recommended.
- Did the dog actually have rabies? That's the big question. When someone is potentially exposed, the best thing to do is to identify and quarantine the biting dog. If the dog had rabies and was shedding rabies virus in saliva, it will show signs of rabies within 10 days. Therefore, if you quarantine the dog and it's healthy after 10 days, it didn't have rabies and no post-exposure treatment is necessary. In this case, it's a stray that was known in the area, and it seems the dog was still around and healthy 15 days after the exposure. So, as long as there is 100% confidence that the dog is actually the same one, then post-exposure treatment is not necessary. The trick is being 100% confident that it's the same dog.
ProMed's monthly rabies update contains some recurring themes:
- A couple of incidents of dog versus rabid raccoon. The dog usually comes out on top, but the raccoon can exact revenge at the end of the day through the need for quarantine or euthanasia. If the dog is not vaccinated, a long quarantine or euthanasia is required. If the dog is vaccinated, only a shorter observation period is needed.
- A rabid skunk was found wandering around during the day with a wobbly gait and drooling. Any wild animal that is acting strangely should be considered rabid until proven otherwise. They don't have to be showing signs of severe neurological disease. Something as simple as not being afraid of people or wandering around in areas or at times when they would not usually be found should raise the suspicion.
- A child who was sleeping outside woke up to "find a raccoon, kind of, scratching at his leg." (I assume they mean it was "kind of scratching at the kid's leg," (whatever that means), instead of it was "kind of a raccoon.") The raccoon wasn't caught for testing but the child is undergoing post-exposure treatment because a normal raccoon wouldn't be expected to do that, so there is a significant chance of rabies exposure. Scratches are not high risk since rabies virus does not live in the claws, however it is possible that saliva from the raccoon could have been present on the animal's feet or the raccoon could have licked the child before scratching, such that the scratches could have then inoculated rabies virus into the tissues.
- A couple of reports of rabies in rabid kittens. These cute little rabies vectors cause repeated problems, and lead to public alerts notifying anyone who may have handled the kittens to get evaluated to see if they need post-exposure treatment. Handling of strays should be avoided.
- A family received post-exposure treatment after being bitten by their rabid cat. Vaccination of pets is not just for the health of the pet. It's to reduce exposure of people as well.
2009 animal rabies statistics have recently been published in the Journal of the American Veterinary Medical Association (Blanton et al 2010). Here are some highlights:
- 6690 rabid animals were identified, along with four human cases. (One of those human cases was associated with travel to India, as described as described in a recent post).
- Rabid animals were identified in 49 states and Puerto Rico.
- 92% of infected animals were wildlife. Raccoons were the winners (actually, the losers, I guess) with 2327 cases, followed by 1625 bats, 1602 skunks, 504 foxes, 300 cats, 81 dogs and 74 cattle.
It is important to remember that these are rabies diagnoses, not all rabies cases. Certainly, more animals died of rabies and were not tested. These numbers may represent the "tip of the iceberg," particularly for some wildlife species. This can impact on the accuracy of the relative numbers between species, and year-to-year changes in cases, but doesn’t change the fact that rabies is present, widespread, relatively common and can infect a wide range of animal species, including pets. It also highlights why vaccination of pets is still important.
A recent edition of Morbidity and Mortality Weekly Reports described a case of travel-associated rabies in a Virginia man. The man was diagnosed with rabies in October 2009. Treatment with the “Milwaukee protocol” (a rabies treatment protocol that resulted in survival of a single patient with rabies but which has not had much success since then) was instituted, however the man died after 25 days in hospital. Thirty-two people who had had close contact with him received post-exposure treatment.
According to his family, the man had an "encounter" with a dog three months earlier in India. The nature of the encounter was not known, and family members didn’t know whether he had received rabies post-exposure prophylaxis. (Considering post-exposure prophylaxis is pretty much 100% effective, I think it’s safe to assume that he didn’t). The rabies virus variant that was isolated was consistent with the strain found in dogs in India, providing more support to the suspicion that the infection was associated with this incident.
Travel-associated rabies is an important problem. This is the 7th case of rabies (and 7th death) in the United States acquired abroad since 2000. While rabies is rare in the US (and many other developed countries) it still kills tens of thousands of people each year, most of whom are infected by dogs. Rabies is endemic in dogs in many regions, including India.
People who are traveling need to be aware of the infectious disease risks in their intended destinations, be it yellow fever, malaria, rabies or others, and take appropriate precautions. Rabies vaccination is not indicated for travelers unless they are going to be working with wildlife or feral animals. The key for travelers is to understand that rabies exposure is a risk, that they must avoid contact with stray animals, and what to do if they are bitten. Access to rabies post-exposure prophylaxis may be limited in some regions, and people who are bitten by a suspicious animal may need to travel home to get proper treatment.
Rabies exposure is considered a medical urgency, but not an emergency, meaning you usually don’t need to sprint to the airport and get treated within a few hours. Rather, it means get to a physician as soon as possible - so don’t continue the rest of your vacation and then head to a physician a week or two later. The more severe the bite and the closer to the head that the bite occurs, the shorter the incubation period might be, so there are some situations where "urgency" and "emergency" are hard to differentiate, but the key is to be aware and get proper care as soon as is reasonably possible.
To me, a good general rule is "avoid buying things that are offered for sale at discount prices by a guy in a parking lot." Unfortunately, many people can't seem to pass up a "bargain" and can end up paying more in the end.
A good case in point is a man who was offering rabies vaccination of pets in retail parking lots in southern Oklahoma. James Allen advertised his vaccination "business" on Craig's List and set up shop in various parking lots. He also signed vaccine certificates and listed himself as a veterinary technician. (One problem is that veterinary technicians aren't allowed to sign rabies certificates. Another is that he is not one). Mr. Allen has yet to be apprehended.
Mr. Allen is suspected of vaccinating hundred of pets with what is, at least from a regulatory standpoint, worthless vaccine. Since the vaccine wasn't administered by a veterinarian, all of those animals are considered unvaccinated. Therefore, if they are exposed to rabies, they face the prospect of euthanasia or a strict six-month quarantine.
Rabies vaccine must be given by a veterinarian in order for government authorities to consider an animal vaccinated in most regions. Mandating that rabies vaccine be administered by a veterinarian isn't a money-grab or veterinarians protecting their turf - it's a government regulation aimed at protecting pets and the public. Restricting rabies vaccination to veterinarians helps ensure that only proper vaccine is used, that the vaccine has been properly handled and administered, and that vaccination is adequately documented. In the absence of clear proof that an animal was properly vaccinated, it has to be considered unvaccinated, because you must err on the side of caution with a deadly disease like rabies.
It's pretty sad that it's so easy to get rabies vaccine in Oklahoma. It should only be available for purchase by veterinarians, but it's apparently easy to obtain from farm and ranch stores. Apparently, stores in Oklahoma can sell the vaccine but are supposed to post a notice saying animals are not considered vaccinated if it's used. Why you'd allow a store to sell the vaccine when you don't recognize it as effective is beyond me, but that's what's happening.
Among the most despicable of the recent consumer frauds in China is the sale of counterfeit rabies vaccine. Eight people in south China's Guangxi Zhuang Autonomous Region have been arrested for producing fake vaccine that may have resulted in the death of one child, and threatened 1000 other people.
The fake vaccine was identified during the investigation of the death of a four-year-old child in December 2009. The child was bitten by a rabid dog and received a series of vaccines from a local clinic. Despite the treatment, he died a few weeks later.
There are at least a couple of very serious concerns with counterfeit rabies vaccines:
- The use of fake, ineffective rabies vaccine for post-exposure treatment in place of real vaccine could result in deaths that could have otherwise been prevented. Rabies is basically 100% preventable if proper treatment (with an effective vaccine) is administered in a timely manner. Without this treatment, exposed individuals are at risk of developing clinical rabies, which is basically 100% fatal.
- Poorly prepared vaccines could themselves lead to serious adverse reactions, because they may contain any number of contaminants to which the body may react. Contamination of "fake" rabies vaccine with live rabies virus is not out of the question - the use of such a counterfeit contaminated vaccines could actually give a person rabies instead of preventing it.
It's not clear which of the above scenarios may have resulted in the death of the four-year-old boy last year. The child died about three weeks after being bitten by the dog, and had clinical signs of rabies at the time of death. Three weeks is an extremely short incubation period for natural infection, but it's not impossible. Short incubation periods can occur, especially with severe bites to the head or neck (the location of the bite in this case was not reported). However, if the "fake" rabies vaccine used to treat the child was contaminated with live rabies virus (which is possible), then it's not impossible that the boy didn't get rabies from the dog bite, but rather was infected by the contaminated vaccine.
Either way, it's not a good situation. Rabies is a major problem in China, with over 2000 deaths last year alone. The last thing people need is confusion about whether they should be vaccinated and fear that the vaccine might be worse than the bite.
The Philippine Information Agency has issued a press release detailing a rabies vaccination program for 5000 public school children in the province of Camiguin. This is prophylactic (preventive) vaccination, not post-exposure treatment.
Routine rabies vaccination is recommended for people at increased risk of exposure. Classically, this involves veterinary personnel, people working with wildlife, people working with strays or feral animals, and similar groups. Routine vaccination of the general public is not used because of the high cost and low need, given the average person's low risk of exposure and the availability of effective post-exposure treatment. By providing vaccine prophylactically, authorities are implying that the rabies exposure risk is quite high for these children.
A Camiguin health office official is reported as saying that the pre-exposure series, consisting of 2 doses, will save money compared to the post-exposure regimen of 4 doses plus a shot of anti-rabies antibody. However, that doesn't make any sense. From a cost standpoint, prophylactically treating everyone with 2 shots only saves money if over half of the population would otherwise need 4 shots. I know rabies is a problem in that area, but certainly half of the kids in the area won't exposed. Further, what really blows a hole in this reasoning is the fact that a vaccinated person who is exposed to rabies should receive a booster series of 2 vaccines regardless, thus bringing the total to 4 shots. People who have been vaccinated don't get the antibody shot if they are exposed, so that does save a little money. (On a side note, routine vaccination usually involves 3 doses, and the release says people will get two doses but will get vaccinated on days 0, 7 and 21 or 28. That's 3 doses, which makes the math even more questionable).
If rabies is epidemic in the area, if it's not being controlled well by other means and if there is rampant exposure of children, vaccination may be a reasonable option. However, rabies is basically 100% preventable with proper post-exposure treatment. Rabies deaths are usually because people don't seek, or are not given, proper treatment in a timely fashion. Educating the public to reduce the risk of rabies exposure and to seek medical care, ensuring that there is adequate awareness about rabies among medical personnel and ensuring that adequate vaccine and antibody is available for exposed individuals seems to be a much more logical approach
I was actually wondering whether this press release was real. I did some searching and this agency is an official government agency and a member of the presidential communications group. It would be really nice to see more details about why this decision was made, particularly some of the evidence that was used to determine that this was needed.
It's important to take rabies control seriously. The main problem with rabies in many areas is a lack of effort or adequate resources directed against stray animal control, animal vaccination, public education, medical education and availability of proper treatment. Working on those would seem to me to be a better approach than an expensive and somewhat questionable mass vaccination program of children. The reasoning in the press release is that kids might not report bites, and that is a good point to consider. But, does that actually occur and can it not be controlled by better education?
What's the cost-benefit of rabies vaccination in a situation such as this? It's hard to oppose vaccination of this fatal disease, but are there other ways to provide better overall protection?
The other night, my daughter woke up yelling that she was "scratchy." She was quite upset and it continued for a while, despite my best attempts to calm her down. She had a bit of a fever and shortly after broke out in a good case of hives all over her body.
How is this relevant to this blog? Well, earlier that day, she was at the doctor's for her 3-year checkup. She wasn't vaccinated, but Heather made the observation that had she been vaccinated at that appointment, we would have wondered whether this was a vaccine reaction.
Determining whether something is a vaccine reaction can be tough. Too often, people blame a wide range of abnormalities on vaccination, without realizing that they occur at other times too.
The post I wrote a couple of days ago about rabies vaccination mentioned people not vaccinating their horses because of fear of vaccine reactions. I think it's fair to say that there are many more people that think their horse has a problem with vaccines than there are horses that truly have vaccine reactions. Sometimes, people are looking for an excuse not to vaccinate. Often, however, they are really convinced that a vaccine reaction occurred, even though the evidence may be weak.
A good example of this is West Nile virus vaccination. When West Nile virus vaccine first became available, there were rumours that it caused stillborn and deformed foals. There were internet sites reporting cases and publishing pictures of aborted fetuses. However, just because a mare was vaccinated and later aborts, that does not mean that the vaccine caused the problem. Lots of mares that aren't vaccinated have problems. That's why we do research - to see if problems like that are more common in vaccinated horses versus unvaccinated horses. Despite the internet paranoia, there is no evidence that West Nile virus vaccination produces dead or deformed foals, and fortunately this rumour seems to have died down. (I have to wonder how many horses died from West Nile because they weren't vaccinated as a result of this rumour. When some people stopped vaccinating children for measles because of false concerns about autism, there were tremendous increases in measles cases in many areas.)
Vaccine reactions can and do happen. There's no disputing that. Most are mild but some can be severe. However, lots of animals can develop identical-looking of problems at any given time. Just because they were vaccinated recently does not mean that the vaccine caused the problem. A vaccine reaction should be considered when abnormalities develop around the time of vaccination, but automatically blaming the vaccine must be avoided.
Some things to consider:
- Has the horse had this specific vaccine before? A reaction is probably less likely if the horse has had this specific vaccine multiple times in the past with no problems.
- Is the problem something that is typically observed with a vaccine reaction? Development of hives after vaccination is pretty suggestive, although it's not definitive. Other problems may be hard to link to vaccination.
- Was a single or combination vaccine used, or were multiple vaccines given at the same time? If a combination vaccine was used and the potential reaction wasn't severe, giving the specific components of the vaccine individually next time might help determine if it is a vaccine reaction and which component caused the reaction. There's no use stopping all vaccinations if the horse might only be reacting to one specific component. Sometimes, avoiding combinations is all that is needed (although whether that's because it decreases the risk of reactions or whether there wasn't actually a vaccine reaction in the first place is debatable). If there is a problem with one component, then that single component can potentially be skipped but the other vaccines still given.
- Was it a severe reaction? If not, then not having the vaccine may be a bigger risk than vaccinating. It depends on the disease and the risk of exposure. Also, pre-treatment of the horse with an anti-inflammatory may be enough to prevent a mild reaction or decrease the severity of a more significant reaction.
- Are there some horses that have severe reactions and can't be vaccinated safely? Yes, but there are very few. Vaccination decisions need to take into account the cost-benefit, in terms of protection and adverse effects. Sometimes, the risks are greater with vaccination, but usually they are not. If you think your horse has a problem with vaccines, work with your veterinarian to determine the best approach. Don't let a knee-jerk reaction automatically prevent you from vaccinating.
Image: A horse with hives along its neck (click image for source)
This Worms & Germs blog entry was originally posted on equIDblog on 16-Sep-10.
TheHorse.com's latest reader poll asked the question "If you knew rabies had been found in wildlife in your area, would you vaccinate your horse for it?"
- 79% of respondents said they already vaccinate against rabies annually.
- 16.5% said they don't currently vaccinate but would if it was found in wildlife in the area.
- 4% still wouldn't vaccinate.
The high vaccination rate is very encouraging and is a good sign, considering that rabies, while rare, is 100% fatal in horses and is preventable with early vaccination.
Here are some reader comments (with some additional commentary from me):
Develop a strong immune system instead try to avoid all the drugs
- Keeping your horse healthy is a good disease prevention measure, but it is not good enough for prevention of rabies. This is a foolish approach to rabies prevention.
Used to yrly. vaccinate in MI, but vets here in KY don't recommend it/My Vet keeps telling me it is not necessary, same with my daughter horses. I disagree.
- This, and a few other comments about veterinarians not recommending vaccination is very surprising and concerning. Rabies vaccination is considered a "core" vaccine in North America and it makes no sense for veterinarians to be actively discouraging vaccination.
Too many adverse reactions...bad outbreak, might reconsider/There have been too many adverse reactions to the vaccine, I won't take the risk of vaccinating.
- Adverse reactions can occur with any vaccine, but they are quite rare with rabies vaccine. Sometimes, horses react when they are given a variety of vaccines at the same time, and it might not be rabies vaccine with that caused the problem. Often, the risk of adverse reactions is just used as an excuse not to vaccinate, even if the horse has never had a problem.
Vaccination is necessary when horses are turned out nearly 24/7
- Yes. It's also necessary when horses are inside 24/7. Wildlife (especially bats) easily and often get into barns.
I don't vaccinate yearly because I test titers and they remain high for many years.
- Titre testing is not useful because we don't know what a protective titre is. You can take a titre and get a result, but that doesn't mean the horse is protected. Also, if your horse is exposed, it would be considered unvaccinated by government officials if it had not been recently vaccinated, regardless of titres.
I would be especially diligent to vaccinate if aware of a wildlife outbreak of rabies/I have only vaccinated when there have been cases of rabies, otherwise, I don't.
- I have a couple of problems with this type of approach. Firstly, you only recognize an outbreak AFTER a large number of animals get sick. Waiting until someone reports an outbreak doesn't help you if your horses are among the first ones affected. Also, rabies isn't a disease that mainly occurs in outbreaks. It is a sporadic disease, where single cases or small numbers of cases pop up all the time. Only worrying about it during an outbreak doesn't help.
I would vaccinate my dogs and cats, but not my horse.
- Why? If there is a risk of the dogs and cats being exposed, there's a risk of the horse being exposed. (Maybe they like their dogs and cats more!)
I can't buy rabies vaccine only vets can get it so I don't give rabies shots.
- So, if I can't do it myself (translation, if I can't do it very cheaply), I won't do it. Not a good infection control program.
NEED ANOTHER CHOICE! I run titers. Vac. is indicated every 3-5 years
- Nope. Vaccination is safe and effective. Standard recommendations are for yearly vaccination. Could we extend that, as is now done with dogs and cats (in which 3 year vaccines are now widely used)? Probably, but we don't have the data to guide us. We can make some reasonable guesses, but do you really want to use a vaccination program designed to protect against a fatal disease to be based on guesses?
The chances of my horses being bit by a rabid critter are slim to none. I don't believe in vaccines
- I don't think anyone can say that the chance of their horse encountering a rabid critter is slim to none. People encounter rabid critters inside their houses, while walking down the street and in various other situations. I certainly didn't plan on catching a rabid bat in my house, but it happened.
- Not believing in vaccines is just ignorance. Vaccination is critical for protection against a wide range of diseases. Can adverse reactions occur? Sure, but they are very uncommon (internet rumour mills aren't facts). Do vaccines prevent infections and save lives? Undoubtedly. What happened when people started avoiding MMR vaccines in kids because of now-discredited autism concerns? Lots of people got sick.
Live in UK, no rabies here generally
- Good reason. Rabies vaccination isn't needed in rabies-free countries.
Fortunately, there were also a lot of logical comments like:
- I never go without this vaccination. it's way to risky!!!
- With all the wildlife around, it's not worth risking an unintended encounter causing big problems.
- Why would you take a chance and not vaccinate...
- Ever since my uncle's horse died of rabies, I have vaccinated all my horses annually.
- Are you kidding? Who'd take a chance with rabies?
And as one person so eloquently put it "DUH!"
Apart from the extremely small small number of horses with known and potentially severe reactions to rabies vaccine (not just any vaccine, specifically rabies vaccine), and those living in rabies-free countries, all horses should be vaccinated.
Image: A Little Brown Bat (Myotis lucifugus) roosting under the eaves of a house (click image for source)
This Worms & Germs blog entry was originally posted on equIDblog on 15-Sep-10.
Israel has experienced a major upswing in canine rabies cases since 2009. There had been a significant decline since 2003, when oral rabies vaccination of foxes was started, but the recent increase has been in dogs and jackals, not foxes. Now, stray jackals and dogs are the main rabies vectors in northeastern Israel, the area affected by the current outbreak.
Stray dogs are a significant concern in terms of rabies because they can have close contact with humans and wildlife. Dogs are the most common source of human rabies internationally and thousands of people die each year from rabies acquired from dogs.
The increase in rabies in stray dogs and jackals has lead to discussions about how to control the stray population and reduce the risk of rabies. Previously, it was common for authorities to shoot strays in parks and nature reserves. This practice was stopped a while ago, however the Israel Nature and Parks Authority has now asked for permission to shoot strays in the interest of rabies control. The proposed regulations would allow strays to be shot in national parks, reserves, and "any other open area where wildlife species are considered at risk", but not unless their presence poses "an immediate discernible risk to wildlife and never within 1 km of human habitation."
This seems to be a wildlife protection program disguised as a rabies control program. The emphasis is on protection of wildlife, since packs of stray dogs have had major impacts on some endangered wildlife (e.g. fallow deer). It's not really a good rabies control program, since culling alone is unlikely to be effective, and only culling when the dogs pose a risk to wildlife and away from human habitation presumably would only have a limited impact on the prevention of human rabies. If they want to control the dog population to protect endangered species, they should just say that. If they want to control rabies, they need a comprehensive rabies control program that involves consideration of various approaches such as vaccination of strays and jackals, sterilization of strays, public education to decrease the risk of exposure, and vaccination of domestic animals. A cull alone won't cut it for rabies control.
Photo: A pair of Golden Jackals (Canis aureus) in Israel (photo credit: Michael Baranovsky)(click for source)
A field worker from Mexico died in Louisiana this weekend from rabies. This is the first case of human rabies in Louisiana in over 60 years, but based on the time the man had been in the country and the incubation period of rabies, it is believed that he was infected in Mexico. Human-to-human transmission of rabies is rare, but healthcare workers and other people he had recent contact with are being evaluated to determine if post-exposure treatment is required. In the case of the man's co-workers, they could have also been exposed to the same source of rabies that infected him.
The original source of infection isn't known, or at least has not been reported. Wildlife are the main source of rabies exposure for people in the US, but dogs are the most common source of human infection internationally. Dog-associated rabies cases in people from Mexico have been previously reported in the US, and it's certainly possible here.
I periodically get questions about whether rabies vaccination is really required or if it's just a good idea. There's not a straight answer because legal requirements vary by region. In Ontario, Regulation 567 of the Protection and Promotion Act states that all dogs and cats three months of age or older that reside in specified areas of the province must be vaccinated. Further, animals must be revaccinated by the date specified on the certificate of immunization. Basically, this means that all dogs and cats must be vaccinated and they must be up-to-date on the vaccination, based on the type of vaccine that was used.
Even if vaccination isn't legally required, if rabies is in an area, it's a good idea because:
- If a pet gets rabies, it will die.
- If a pet gets rabies, owners or other people in contact with it may need post-exposure treatment.
- If a pet gets rabies, it could infect people with this almost invariably fatal disease.
- If an unvaccinated pet gets exposed to rabies, it will need a strict 6-month quarantine or euthanasia. (Euthanasia is common in these situations.) If the pet was vaccinated, all it needs is a 45 day home observation.
Rabies vaccination of pets is easy, cheap and safe, and often required by law.
Image source: http://amcny.wordpress.com
Yet again, a large number of people are undergoing rabies post-exposure treatment because they were exposed to a rabid raccoon that was "adopted" from the wild. In this case, a North Carolina family found a baby raccoon at the side of the road and decided to bring it home. Over the next couple of weeks, various family and friends handled the raccoon, and many were bitten or scratched in the process. The raccoon then died and was identified as being rabid. Forty-five people are now being assessed to determine whether they need to be treated for rabies exposure.
The family dog, which was unvaccinated, has been taken by Animal Control and now faces either a six-month strict quarantine or euthanasia. I suspect the dog will be euthanized.
So, this probably well-meaning but misguided action has resulted in:
- the need for costly post-exposure treatment of many people
- presumably a stressful period for many of those people
- probably the death of the pet dog (although not having the dog vaccinated played a big role here too, since if it was vaccinated, it would only face a 45 day observation period at home, not a strict six-month quarantine or euthanasia).
Fortunately, the raccoon was tested. Otherwise we might be talking about human deaths from rabies, instead of people needing post-exposure treatment. The people who took in the raccoon could also face charges since keeping wildlife without a permit is illegal, but it sounds like that's unlikely to occur.
A few take-home messages from a situation like this:
- Leave wildlife in the wild.
- Vaccinate your pets.
- If you are exposed to an animal that is acting strangely, make sure it's tested for rabies (they did this right, at least).
I had an advice call the other day about two cats that were found with a dead bat. One cat was vaccinated against something (not sure what or when) while the other cat was unvaccinated. This is a situation that, if managed properly, can be very minor, but if handled improperly, can be a major problem, even resulting in death of the animals.
Bats are notorious rabies vectors. The odds of this bat carrying rabies are probably low, but they are not zero and a rabid bat is going to be more easily caught than a healthy bat. Any contact of an animal with wildlife in areas where rabies is present is considered a possible rabies exposure unless proven otherwise. The only way to do this is to have the bat tested.
If the bat is tested and is negative, then everything's fine. If it's positive, then the vaccinated cat would need a rabies booster vaccine and would have to be observed at home for 45 days. The unvaccinated cat would need a strict six month quarantine or would have to be euthanized. So, it's clear that the rabies status of the bat and the vaccination status of the cats are crucial.
Here's what to do in a case like this:
- Get the bat. The bat needs to be tested so you have to maintain control of it. Don't let the cat eat it or run off with it. Don't leave it outside where a person or animal could walk off with it. Put it in a bag or container, without having direct contact with it (e.g. use gloves or a scoop to pick it up). Be very careful if it's not completely obvious that the bat is dead, because an injured bat might look dead but still be able to bite.
- Submit the bat for testing. In Canada, that's done through the Canadian Food Inspection Agency. Make sure they know that an animal has been exposed to the bat. They would not likely test the bat if there was no exposure. They can be contacted directly or through your veterinarian. There is no charge for testing.
- Find out the vaccination status of the cat(s). You need to know when the last rabies vaccine was given and what type of vaccine was used (1 year or 3 year). You need to be able to demonstrate that the pet is current on its rabies vaccination if the bat is positive and you want to avoid the long quarantine.
- Figure out why/how/where the cat(s) caught the bat, and whether that can be avoided in the future.
- Roaming pets + wildlife = bad news: One person's dogs killed a raccoon while out for their "romp around the yard." The raccoon was rabid. There's no mention about the vaccination status of the dogs. If they were vaccinated, they probably got a rabies booster and are under a 45-day "house arrest" for observation. If not, they either need to be placed under a strict 6-month quarantine at a separate facility, or they'll be euthanized. Another report describes a different dog that is now under a 6-month quarantine after attacking a raccoon. In yet another report, a North Carolina woman's dog was euthanized because it killed a rabid fox and was unvaccinated (the owner chose euthanasia over quarantine). That dog is now dead mainly because the owner didn't take the simple and relatively inexpensive step of ensuring that her dog was vaccinated.
- Pissed-off wildlife bite. Sometimes they're rabid too. Get too close at your own peril: A South Carolina man is undergoing post-exposure treatment because he was bitten by a raccoon while removing it from a trap. I'm glad that he had the animal tested. It's pretty easy to see someone in a situation like this just yelling at the raccoon and letting it go, thinking they were bitten because the raccoon was upset and not realizing that they might have been exposed to rabies.
- Some people just don't get it: In response to rabies exposure of close to 50 church members from a rabid bat while on a mission trip, the mission leader stated "It's just part of being in rural America, so there's really not a lot to talk about." Ugh. Rabies exposure should not be written off as some benign, unavoidable rural American experience. It's exposure to an almost invariably fatal disease that requires a series of expensive treatments. It's also not a rural thing. Rabies exposures can occur commonly in urban areas as well.
- Stray kittens can be cute but deadly: A rabid cat and kitten were identified in Ocean City, Maryland, and authorities are looking for people that may have come into contact with them. Human exposure to rabies from handling cute but infected kittens is not uncommon, and sometimes involves a lot of people. If you see a stray kitten, it's best to leave it alone. If you feel the need to rescue it, make sure that you get it to a vet for an exam, and that it subsequently goes somewhere where it can be properly observed and taken care of. If you're bitten in the process, make sure the kitten is quarantined for 10 days to see if it's rabid, or euthanized and tested. The worse case scenario is when people play with stray kittens, get nipped in the process, dismiss it as a minor or playful bite, then release the kitten back into the wild, never knowing whether they might have been exposed to rabies.
Trap/neuter/release (TNR) programs involve trapping feral (stray) cats, then spaying or neutering and vaccinating them. Some cats are adopted, while the majority are released. The goal is to reduce the feral cat population by limiting the number of breeding animals, and to increase overall vaccine coverage in order to reduce illness and deaths. One such TNR program has come under fire in a Texas town.
In Leander, Texas, trapping wild animals (including feral cats) is illegal, but authorities have ignored the rules for groups that run TNR programs. One citizen, Carmen Amaya, is leading a charge to get authorities to start enforcing this so that TNR programs can't happen. The main reason appears to be that she's upset her dog was scratched by a feral cat and ended up with $800 in vet bills (not something I'd be happy with either, but is this really the best way to direct her anger?).
A non-profit group, Shadow Cats, has led the TNR effort and has trapped, neutered and vaccinated about 3000 cats in Central Texas since 2004. About 500 were adopted and the rest released. The organization knows they are working outside the law and have lobbied for it to be changed. That was being considered in June, but opposition from Amaya and others has led to the creation of a task force to make a recommendation, which is due next month. In the meantime, Shadow Cats has ceased activities in Leander.
I'm not sure what the opponents to TNR really want. If it's just cessation of the program, there's no benefit to them. Without the program:
- Stray cats will continue to be around, and there will probably be more of them.
- Potentially adoptable cats won't be taken into homes to improve the lives of those cats.
- Vaccine coverage of the population will decrease. That's a critical point, because it will result in lower "herd immunity." With herd immunity, the greater the percentage of a population that is immune to a disease (i.e. vaccinated), the lower the likelihood of the disease establishing itself in and spreading through the population, even among those individuals who don't get vaccinated.
On the other hand, if these people simply want Shadow Cats to stop releasing the neutered cats back into the neighbourhood, it means either 1) finding a way to care for all those cats in shelter, which simply isn't realistic for a multitude of reasons, not the least of which is cost, 2) releasing the cats elsewhere, which doesn't actually solve the problem, it just makes it someone else's, or 3) euthanizing all the cats instead of neutering and releasing them. If they're hoping that by objecting to the TNR program that all the cats being trapped will be euthanized instead, they need to realize:
- It's not going to happen as long as volunteer "rescue" groups are in charge of the program. These groups aren't going to trap and kill.
- The city is unlikely to do it either, and there's a cost to having city personnel catch the cats and take them somewhere to be euthanized.
- Most importantly, culling has been shown time and time again to be an ineffective way to control feral animal populations. What's needed is a combined approach that includes measures such as neutering and vaccination, education to reduce the risk of human and domestic animal exposure to feral animals, and taking steps to discourage feral animals from spending time in close proximity to people and domestic animals.
Amaya states that "her" feral cat is a nuisance and she doesn't want it on her property. So what is she trying to accomplish? If anything, her actions will just help her single stray cat turn into a large extended family of stray cats that are susceptible to rabies.
There are certainly concerns with feral cats and TNR programs. They are not perfect and not always run well. Some people are opposed to them for various reasons, some of which are quite reasonable. It's a tough issue because one person's idea of success might be completely different from someone else's. Some people focus on the number of animals, while others focus on the quality of life of the animals, public health aspects, impacts of feral cats on wild bird populations and other diverse areas. A local council isn't going to be able to solve these problems, and it really comes down to an assessment of the potential usefulness of the program and the ability of the people involved to do it safely, ethically and legally.
Personally, I'd rather see well-designed, well-run and regularly-evaluated programs to try to reduce feral cat (and dog) populations, and (perhaps more importantly) increased vaccination coverage in the feral animal population, than nothing. Feral animals aren't going to disappear if we ignore them.
Image source: www.shadowcats.net
Former British pop star and I’m a Celebrity-Get Me Out of Here reality TV character Samantha Fox was bitten by a rabid cat while vacationing in Thailand. Fox was feeding stray cats near a restaurant and was attacked.
Having contact with stray animals is a high risk activity, particularly in regions where rabies is very common. When traveling, it’s important to understand the infectious disease risks in the areas you visit, and rabies is one of them. A bite by a stray animal is usually going to be considered a potential rabies exposure, unless you’re in a rabies-free country or the animal is available for observation or testing. That’s not usually the case, and post-exposure treatment, consisting of a shot of anti-rabies antibody and a series of 4 rabies vaccinations, is usually required.
Fox wasn’t particularly impressed by the treatment: "The treatment for rabies makes you feel sick and horrible, though, really fluey and shaky." Usually, the post-exposure treatment isn't too bad (I can speak from experience here) and current rabies vaccines tend to have a much lower rate of side effects than older vaccines. Fear of adverse effects shouldn’t be a deterrent to proper treatment of this almost invariably fatal disease.
It's not like we needed any evidence that rabies is still an active, deadly disease, but a recent ProMed-mail posting contains 16 different rabies notices. They include:
- An animal control worker who was bitten by a rabid, stray cat that was trapped by a person in Texas.
- Rabies exposure in an unvaccinated dog in Maryland, that resulted in euthanasia of the dog because the owners didn't want to undertake the required 6 month quarantine for exposed, unvaccinated dogs. The dog was exposed to rabies virus while killing a raccoon.
- Diagnosis of rabies in two trapped raccoons in New Jersey.
- Rabies exposure in an Arizona woman who was attacked by a rabid fox while in her yard.
- More marauding (presumably rabid) foxes attacking people and dogs in Maine and South Carolina.
- Rabid bats and skunks in Colorado.
- A rabid fox in Alabama.
- Rabid raccoons in Virginia.
- A rabid raccoon attacking a vaccinated dog.
- Rabies exposure in people bitten or scratched by rabid stray kittens in New Jersey, Nebraska and Georgia.
Common themes or take home messages:
- Rabies is here (in most areas, at least) and it's unfortunately not going away any time soon. We can reduce the number of affected animals and decrease the risk of exposure of people and domestic animals, however, with good prevention strategies.
- Vaccination of pets is a cheap and effective way of protecting them, and anyone they are in contact with.
- Keep pets away from wildlife.
- If you are bitten by a wild animal, you must consider it a potential rabies exposure unless the animal can be proven not to have rabies.
- If you see an animal that is acting strangely, stay away and call animal control.
Bali's rabies outbreak continues to claim lives, largely because of inadequate access to proper healthcare. The death toll from this outbreak, which has been ongoing for about two years, is officially 58, although the true count may be higher.
The latest case was a 57-year-old temple priest who was infected after trying to break up a fight between strays dogs and his puppy. He was bitten by a stray dog in the process, but did not receive any post-exposure rabies vaccination because of a vaccine shortage. Rabies is basically 100% preventable when proper care is provided after an exposure, but inadequate access to proper treatment remains a problem, particularly in certain areas and in less developed countries. The priest started to develop signs of rabies about two months after the bite, which is a pretty typical time frame. Once signs of rabies are present, it's almost invariably fatal, and he unfortunately succumbed to the disease shortly after being hospitalized.
Despite ongoing efforts to control this outbreak, rabies remains a serious problem in Bali, and many stray dogs remain unvaccinated. Inadequate education of the public is a problem since not everyone who is bitten goes to a doctor, especially for minor bites. However, even if people go to a doctor, the shortage of rabies vaccine is a huge problem. This whole situation is clearly not under control.
Visitors to Bali need to be aware of this ongoing outbreak. If you are traveling to Bali:
- Avoid contact with stray dogs. You never know who's rabid.
- If you are bitten, promptly clean the wound and get to a physician.
- If you are bitten by a stray, make sure you get post-exposure treatment: a shot of anti-rabies-antibody and 4 (previously 5) rounds of vaccine over a few weeks. If you can't get the treatment started in Bali, get it as soon as possible. Rabies exposure is not an emergency, but you don't want to unnecessarily delay treatment. You don't need to be immediately evacuated from the country to a place you can be treated, but at the same time, you don't want to take your time, travel for a while, then get vaccinated a week or two later. You'd probably be fine, but rabies is not something with which to take chances. The incubation period is variable and the rapidity of onset depends in part on the severity and location of the bite. In particular, a severe bite to the head or neck region would be an indication for very prompt treatment. So, if you're bitten, don't panic, but try to get back home and get treated as soon as is reasonably possible.
Rabies vaccination of people planning on visiting Bali is not recommended, unless you are planning on having contact with dogs. If you are going to Bali to take part in stray dog vaccination, then rabies vaccination would absolutely be indicated. Otherwise, it's not really something that's needed. If you don't get bitten, you won't get exposed, and a little common sense goes a long way toward avoiding dog bites.
The Galesburg Register Mail headline says "Dogs killed for eating rabid bat." It's true, but the more accurate description would be "dogs euthanized because owners failed to vaccinate them." In yet another unfortunate outcome of failure to properly vaccinate pets, two dogs from Galesburg, Illinois were euthanized after being exposed to a rabid bat. They were found chewing on the dead bat, which was subsequently diagnosed with rabies.
When an unvaccinated animal has been exposed to rabies, there are typically 2 choices:
- 6 months strict quarantine
The owners couldn't afford the cost of quarantine and decided to euthanize the two dogs.
The sad part is that this was a completely preventable problem. If the dogs were vaccinated, they would have only had to undergo a short period of owner observation, not a long and strict quarantine. Rabies vaccination is cheap insurance for your pets' (and potentially your) health.
Recent reports of a woman in Texas that "contracted rabies" are great examples of less-than-careful reporting. The headlines look dramatic, and a couple of articles state that a woman bitten by a puppy "contracted rabies", but it's far from the truth.
Here's the real story, as far as I can tell:
- A litter of stray puppies was taken to a shelter and then sent to a foster home.
- The woman who took them in was bitten in the leg.
- She received medical care and took the puppy to a vet. The vet euthanized the animal because of the aggression it was displaying and had it tested for rabies.
- The puppy was positive for rabies and the woman is undergoing post-exposure treatment.
It's not a nice situation for the person that was bitten, but it's not exactly a rare event and post-exposure treatment for rabies, when given properly, pretty much has a 100% prevention rate.
Authorities are also trying to track down any people that may have had contact with the puppies before they were taken to the shelter, to determine if more people need post-exposure treatment.
Strangely, the other puppies are being isolated for 45 days, after which time they will be put up for adoption (assuming they don't develop signs of rabies). This doesn't make a lot of sense. Standard recommendations are that unvaccinated animals exposed to a rabid animal should be euthanized or quarantined for 6 months. The 6 month quarantine is in place because rabies can take a long time to develop after exposure. Since these puppies came in with the sick one, and it's almost certain there was no information about their vaccination history, they have to be considered exposed and unvaccinated. This is true even if they were vaccinated at the time of arrival because they could have been exposed before vaccination. Further, animals are not considered protected until 28 days after vaccination, and exposure within 28 days of the first shot is the same as exposure of an unvaccinated animal.
In this case, it was pretty easy to determine that the woman didn't have rabies in some, but not all of the articles. I particularly liked how one of the stories described how rabies "eats away at the brain," a description you wouldn't expect to see from a more mainstream source.
Presumably, the woman who was bitten will be left with nothing more than some bad memories and an increased awareness of rabies. Hopefully the shelter reviews its policies to determine whether this could have been prevented and whether other measures should be in place to reduce the risk to people who foster animals. At a minimum, this would include ensuring foster homes know about the risks, know to get the animal to a veterinarian if it begins to act strangely (as this woman did) and ensure that other pets in the household are properly vaccinated.
My parents adopted a cat from their local OSPCA shelter the other day. He's an adult cat (maybe named by now, but not at last report) and he came:
- vaccinated against the typical group of feline diseases
- dewormed with fenbendazole
- treated with metronidazole (an antibiotic - it wasn't clear whether this was because he had diarrhea at some point or was diagnosed with something, or whether it was just a routine practice)
- treated with Revolution for flea control
The one thing that's missing from the list is vaccinated against rabies, which I find amazing. Apparently, the cat was given everything they can give at the shelter without the need for a veterinarian. (Presumably the cat came in neutered, because that would hopefully fall under the "need a veterinarian to do it" category. Prescribing an antibiotic would also be something I'd hope would involve a veterinarian.)
Sending cats to new homes without vaccinating them for rabies is bad practice. Rabies is a rare but extremely serious disease. Vaccination is critical, safe and easy. The OSPCA website says that not all shelters vaccinate against rabies. Some shelters have veterinary staff in the facility, so rabies vaccination would be standard there. Other shelters work with local vets to do this, but that's not universal, apparently. I don't see why this isn't a mandatory policy for the OSPCA. Yes, there is a cost to it, but that should be a cost of doing business. Rabies vaccines aren't expensive and many vets would work with groups like this to keep the costs down. Adopting an animal from a shelter isn't cheap, and recovering the small added cost of the vaccine should be possible. I'm not sure whether it really is a question of cost, accessibility or simply not bothering. Getting a veterinarian involved also has benefits beyond just giving the vaccine. Potential health problems can be identified, including diseases that could be transmitted to people that adopt the animals.
It's true that lack of vaccination of adopted pets can be addressed by getting them vaccinated right after adoption. Any pet that has been adopted (or purchased, or otherwise obtained) should be promptly examined by a veterinarian to identify any potential problems, and to make sure the pet is on a proper preventive medicine program. Realistically though, not everyone does this. While you don't like to set policies according to the lowest common denominator, you need to for a deadly disease like rabies when the consequences to people and pets are so high. I find it hard to justify sending any animal out of a shelter without rabies vaccination.
Image source: www.ontariospca.ca
A canine distemper outbreak has been identified in raccoons, dogs, coyotes, foxes and skunks in Los Angeles County. Local residents are being reminded to vaccinate their dogs against distemper and report any suspected signs of distemper to their veterinarian. (Keeping their pets away from wildlife should also be recommended.)
Distemper is an infection caused by a virus which is related to the virus that causes measles in people. It can cause different types of disease in dogs, raccoons and some other wild mammals, but neurological disease is often present and can appear similar to rabies.
Canine distemper cannot be transmitted to people, but, in a roundabout way, distemper outbreaks can be a public health concern. This is because of the potential for rabies cases to be mistaken for (and dismissed as) distemper cases, leading to increased exposure of people to rabid animals.
Quite a few years ago, there was a cat with neurological problems under my parents front porch. It was a stray cat that had been in the neighbourhood for a while, and which sometimes interacted with people. When the local authorities were contacted, the response was "Don't worry, it probably has distemper." This was probably true, and since there was no known direct contact with people (something that is difficult to really know in a social stray) testing for rabies wasn't done. However, the concern is that rabies cases will be missed, or, more concerningly, human exposure to rabid animals will be missed because of the assumption that it's really distemper.
Understanding disease patterns in an area is important when determining the likelihood of a particular disease and the appropriate response to a sick animal. At the same time, you can't get complacent and assume that trends are absolute. With an almost invariably fatal disease like rabies, you have to be careful not to overlook the rare case amongst large number of other, similarly appearing diseases. If someone has contact with an animal suspected of having distemper, the potential for rabies exposure must not be forgotten.
Image source: http://weblogs.baltimoresun.com
A large rabies outbreak continues in Moscow. There were 257 rabies cases reported in the area in 2009 - ten times the number from previous years, and well above the very low numbers that occurred for a decade of so after an aggressive control program to control the post-World War II rabies epidemic. Control of that outbreak mainly involved shooting of potential rabies vectors: stray dogs, foxes and raccoon dogs.
Various more humane but still aggressive control measures are being considered to help control the current epidemic, including banning movement of pets to suburban cottages (probably better to just vaccinate the pets first), canceling a dog show (pretty low yield - better to vaccinate), and mass immunization of wild and domestic animals (the key approach).
An aggressive approach makes sense. Rabies is almost invariably fatal and large numbers of people who are exposed require post-exposure treatment every year. Local wildlife population patterns, wildlife rabies hotbeds and rates, pet numbers, pet movement and vaccination must all be considered when determining the best approach to control. Apparently, about 30 000 pet dogs visit cottages in the Moscow area each weekend, and there's concern that they could bring rabies back to the city with them. Authorities have warned about traffic jams that might develop, presumably from police stopping traffic looking for contraband canines. However, instead of banning dog movement, it would likely be more effective to increase vaccination (or even mandate it for dogs in those high risk regions) and control roaming dogs. If a dog doesn't roam freely in the country, it's less likely to encounter a rabid animal. If it's vaccinated, it's unlikely to get infected if it does get exposed. If it's not allowed to roam when it returns to the city, it's less likely to spread rabies to other animals and people in the very rare event that it was exposed and infected. Furthermore, if wildlife are vaccinated through rabies bait drops, the chances that a roaming dog will be exposed get even lower.
Ensuring the highest possible canine vaccination rates is the key measure. Whether that's through mandating vaccination, providing it at low cost, or making it more convenient for owners to get it done, it's a great place to focus efforts and resources. In principle, it's a simple concept. In practice, it can be more difficult, especially when compliance of the general public is required.
For those of you that want to practice your Russian reading skills, here's the original story.
A man from Jharkhand, India, was bitten by a dog and realized that there was the potential for rabies transmission. That's good, particularly given the huge problem with rabies in India. However, he didn't take the recommended approach of proper wound care and getting post-exposure vaccination. Rather, he killed the dog (getting bitten a few more times in the process), cut out its heart with a pair of scissors and ate it raw, exclaiming that now there would be no problem with rabies.
Not a good idea.
Rabies is widespread in India. Every year, 25 000-30 000 people die of this disease. A person in India is bitten every 2 seconds and someone dies of rabies every 30 minutes.
Every dog bite needs to be considered a possible rabies exposure. If a dog that bites someone is not available for quarantine or testing to determine whether it has rabies, post-exposure treatment is necessary. That involves an injection of anti-rabies antibodies and a series of 4 or 5 vaccines, not ingestion of the animal's heart.
Hopefully, the dog didn't have rabies and this will go down as a somewhat curious little story. Unfortunately, if the dog had rabies, there is a good chance that this person has been infected, and if infected, he will almost certainly die.
Eating an animal's heart to prevent rabies transmission may just be a bizarre belief of an unusual individual. This is something that needs to be investigated, however, because if the same belief is held by many other people in the area, they will all put themselves at risk if they are bitten by not seeking appropriate and effective treatment. Not only does killing the dog and eating its heart have no chance of preventing infection, it probably increases the risk of rabies by leading to more bites. More rabies education is often needed in problem areas, and this may be the case here.
Image: Canine heart (source: www.historyforkids.org)
In response to an ongoing rabies outbreak, Thailand has launched a program to vaccinate stray dogs. A posting to ProMed questioned this approach.
"The authorities plan to catch stray dogs, to vaccinate them, and to release them. This is inadvisable, since rabies incubation in dogs may extend to a year, although it is mostly between 2-3 months. Catching an animal which might already be incubating an infection and then vaccinating it will not only not protect the animal but put at risk the lives of people led to believe that the animal is safe", wrote Maya Kimchi.
True, you could not guarantee that a dog that was caught was not incubating rabies, and in that case, vaccination of the dog would not be effective. However, the odds of this are very low, and it doesn't make sense to not vaccinate. The worst case scenario is you have a dog that develops rabies, that would have developed rabies anyway, but it is less likely to spread it to the other dogs you've vaccinated. There would be no risk to people vaccinating the dog since it wouldn't be infectious at that point.
"In an endemic country where there are many stray dogs and many cases of rabies in animals and humans, as in Thailand, the solution of [the problem] of stray dogs is to reduce their number and carry out mass vaccination to all owned dogs, cats, and ferrets."
The problem is the stray animals. Vaccination of pets is very much an important component, but vaccinating pets and ignoring the reservoir (stray dogs) doesn't help in the long run.
"If a country decides to avoid the elimination of stray dogs, it will be necessary to catch them, to vaccinate them, and to [quarantine] them for 6 months at a minimum, and only subsequently, together with birth control measures (castration/sterilization), release them for adoption, after registration in a database for further control."
Here's what the World Health Organization's Expert Consultation on Rabies says:
"Mass canine vaccination campaigns have been the most effective measure for controlling canine rabies."
"There is no evidence that removal of dogs alone has ever had a significant impact on dog population densities or the spread of rabies. The population turnover of dogs may be so high that even the highest recorded removal rates are easily compensated for by increased survival rates."
"Attempts to control dog populations through culling, without alteration o f habitat and resource availability, have generally been unsuccessful."
Culling is rarely the answer. Vaccination of stray and pet dogs, education of the public to avoid contact with stray dogs, controlling roaming of pet dogs to decrease control with strays, educating the public about the need for post-exposure prophylaxis if they have been bitten by a stray dog and ensuring that the healthcare system has the appropriate resources (e.g. available rabies antibody and vacccine) and knowledge to handle exposed individuals is the best approach.
In response to ongoing problems with rabies in raccoons in New York's Central Park, a vaccination program is now underway. Raccoons are being trapped, vaccinated, tagged and then released. This is a logical response to the outbreak and one that will hopefully have a significant impact.
Trap, vaccinate and release programs can help in a few different ways. Firstly, they protect the individual raccoons that are vaccinated. However, in the bigger picture, mass vaccination is designed to protect humans and animals beyond those that are vaccinated (this is referred to as "herd immunity" - click here for a good video about this concept from a previous post). As the number of vaccinated (and therefore immune) individuals in a population increases, there's less risk of ongoing transmission of the disease (in this case, rabies), since an infected animal is less likely to encounter a susceptible (unvaccinated) individual. If, on average, an infected individual does not have a chance to infect another individual, the outbreak will eventually die out. The key is getting a high enough percentage of the population vaccinated.
For eradication of dog rabies, the World Health Organization recommends vaccinating at least 70% of dogs in a population. I'm not sure what the critical number is for raccoons, but it's presumably a similar, and reasonably high, number. Since a high vaccination rate is needed, there needs to be a concerted effort to do more than just a token vaccination program. It also helps if there's good information about raccoon numbers and distribution in the area. As long as the Department of Health is serious about this program and puts the required time and resources into it, the odds are very good that it will be successful.
Eight more rabid raccoons have been found in New York's Central Park over the past two weeks. These, plus the 12 rabid raccoons reported in the park last year, represent a major increase in disease frequency since only 1 rabid raccoon was identified in Central Park from 2003-2008. That's a concerning development given the number of people that visit this 843 acre park in the heart of New York city every day.
In response, the city's Health Department has started an education campaign to alert people to the risk, and tell people to stay away from wildlife, report any sick animals and to keep their dogs on leashes. Every pet owner also needs to make sure their dog's rabies vaccine status is up-to-date, even if they always keep their dog on a leash, because you never know what a rabid raccoon will do (such as attacking a leashed dog that walks by). There are also plans to vaccinate raccoons in and around the Park, however I couldn't find details about what type of vaccination program will be used.
Rabies has been diagnosed in a 6-week-old Jersey calf at a Maryland educational centre, raising concerns about exposure of farm visitors, particularly groups of school children. At least 70 kids and an unstated number other visitors had recently visited the farm.
Fortunately, the farm in question is not open to the public, so they should have an easier time identifying people who have been there (e.g. school groups). Contact tracing is underway to try to identify people that had contact with the calf. Simply petting the calf or being in the general area does not pose a risk. The main risk would be from contact of open wounds with the calf's saliva, or a bite. We don't typically associate bites and calves, but it can happen when calves are allowed to suck on someone's fingers - if the person sticks their hand in too far he/she may get chomped by the calf's sharp molars. Public health personnel are trying to identify people who had contact with the calf, then they'll determine whether there was a chance of exposure to the virus. People that were potentially exposed to rabies will undergo post-exposure prophylaxis, consisting of a shot of anti-rabies antibodies and four doses of vaccine over the course of a month. Not fun, but much better than getting this almost invariably fatal disease. At least nine students have started treatment so far.
Petting zoos and similar events are a concern in terms of disease transmission because of the large number of people that can be exposed to animals and the high percentage of children that are involved. Rabies is uncommon in petting zoo animals, but it is periodically identified at such a facility/event, often resulting in the need for post-exposure treatment of large numbers of people. Vaccination of petting zoo animals against rabies should be a standard practice. This calf, being only six weeks old, was too young to vaccinate, but if the calf's mother was vaccinated the risk of rabies would be lower (because the calf would get antibodies from the mother). There's no information about the cow's vaccination status or much else about the calf, apart from it being a recent acquisition.
The fact that a recently acquired young calf was allowed to have contact with the public is questionable management, because young calves are a high risk group for certain infectious agents like Cryptosporidium and Salmonella. The CDC recommends that children less than five years of age not have contact with young calves. Since young kids are frequent visitors of places like this, having calves (or at least letting people have direct contact with them) is quite questionable as well. Hopefully there will be a good review of vaccination, animal acquisition and animal contact protocols for this facility to reduce the risk of future exposures to rabies or other infectious diseases.
I received newsletter today from Intervet (a pharmaceutical company) that is targeted at equine veterinarians. One article discussed rabies in horses. It wasn't bad overall, but I thought the section on what to do when a horse might have been exposed to rabies was worth discussing.
The article asks, "If your client suspects that a horse has been bitten by a rabies-infected animal, what should be done?"
Answer: "Contacting you as the veterinarian is always the first step."
Great first step. A second step that wasn't mentioned should be, "Try to identify and (safely) capture the animal that bit the horse." This is often impossible but certainly worthwhile if it can be done. However, if you're trying to catch the offending animal, make sure you don't put yourself at risk of exposure to rabies in the process. If the animal can be caught, it's rabies status at the time of the bite can be determined (either through testing or quarantine). If it can be shown that the animal wasn't rabid, a lot of stress, hassle and expense can be saved.
"If the horse was previously vaccinated... Then isolate and observe the animal for 45 to 90 days (your clinical evaluation will involve gait analysis, radiography and a spinal tap)."
Boosting the rabies vaccine is also a good idea. The next step, however, needs to be contacting local regulatory officials to find out what you have to do. They determine if, how and how long an animal needs to be quarantined - this is NOT the decision of the local veterinarian nor the animal's owner. Most likely, they will recommend a 45 day quarantine for a vaccinated horse, since this is what is recommended in the NASPHV Compendium on Rabies. The discussion of diagnostic testing makes no sense. There is absolutely no indication to perform diagnostic tests on a horse that has been bitten by a rabies suspect. None. There are no tests that can be used to diagnose rabies in live horses (also exposed horses don't instantly develop signs of rabies). Horses should be monitored closely for signs of rabies during the quarantine period, but that's it.
"...and have the client make a list of all people who had contact with the horse."
This is often done when horses have or are suspected of having rabies, but not horses that are potentially exposed. It is done to help public health personnel contact people that may have been exposed to rabies. A horse that was just bitten by an animal is not a risk for transmission of rabies. (However, keeping a list of people who have contact with the horse after it's been bitten (i.e. durng the quarantine period) - which should be as short a list as possible - is a reasonable precaution in the unlikely event that the horse does develop rabies.)
"If the animal was not vaccinated, your options are to euthanize and perform a postmortem examination of the brain (the only way to definitely confirm rabies)..."
Euthanasia is one of the options that needs to be considered in an unvaccinated horse that has been exposed, which is one of the reasons that identifying the biting animal and testing it is critical, if it can be done. The last part of the above sentence (from the atricle) is complete nonsense. Why would you test the brain of a normal horse that has been euthanized because it's just been bitten by a potentially rabid animal? The horse isn't being euthanized because it has rabies, it's being euthanized because of the likelihood of it developing rabies weeks to months later. Testing of the brain will tell you absolutely nothing if the animal was only bitten recently.
"...or isolate and observe the horse for six months and develop the human contact list."
Again, this needs to be decided based on discussions with regulatory personnel who are responsible for dictating what is to be done. A six-month quarantine is a pretty standard recommendation for an unvaccinated animal. Creating a human contact list should not be necessary, since quarantine involves severely restricting contact of people with the horse and only a few (ideally one) person would have any type of contact.
The article wraps up with the very true emphasis on vaccinating horses. It's a cheap measure to prevent a relatively rare but invariably fatal disease.
This Worms & Germs blog entry was originally posted on equIDblog on 05-Jan-10.
.A Texas couple is undergoing rabies post-exposure prophylaxis after an abandoned puppy they adopted was diagnosed with rabies. They found the puppy outside and brought it into their house. One of them was subsequently bitten and they found out about the rabies diagnosis on Christmas eve.
One of the couple is quoted as saying "The doctor said 'It was a good thing they didn't wait until Monday, because it would have been too late. We couldn't have given you the shot because it wouldn't have done any good. You would have been dead within 48 hours." I really hope they completely misinterpreted what the doctor said, otherwise the doc has no clue about rabies. Prompt treatment is the goal, and you certainly don't want to wait any longer than you have to, however rabies doesn't kill in 48 hours, and you can start post-exposure treatment any time (just the sooner the better).
The couple also have seven other pets, who may also have been bitten. There wasn't any comment about what's happening to those pets. Hopefully they are properly vaccinated so they can be given a rabies vaccine booster and only undergo a short-term "quarantine" at home with the owners. (The alternative is immediate euthanasia or strict, long-term quarantine for months).
This isn't a new scenario - adopting a stray animal then finding out it has rabies. The less you know about an animal at the time of adoption, the greater the risks. I'm certainly not saying don't adopt a stray animal. But, if you are going to do it, recognize the risk, make sure you are in a low-risk household (everyone's susceptible to rabies, but some people are at greater risk for other zoonotic diseases and stray adoptions should be avoided by them), get the animal examined by a veterinarian as soon as possible, and make sure that it gets examined by a veterinarian if it develops any signs of disease.
All this leads into another another story I read a few days ago. Basically, it was a feel-good story about someone who found some puppies, stopped by a nursing home (or similar facility) and the facility adopted one or more of the puppies. This demonstrates some good points (e.g. resident's presumably had a great time watching the pups) and bad points (e.g. disease exposure, unknown temperament, injury risks from rambunctious puppies...) of animals in long-term care facilities. What if the puppies that were adopted by the home had rabies? It's happened before, and you end up having to administer post-exposure prophylaxis to a large number of people that already have enough health issues and risks. Nursing homes and other facilities should never adopt stray animals. Hopefully we don't see a news release in the next few weeks about widespread rabies exposure in that facility.
Video from wfaa.com
Last week, I wrote about the uncommon situation where a child was attacked by a 60 pound beaver. Any bite from a wild mammal, especially one acting different than normal, needs to be considered a possible rabies exposure, and I was impressed that the family pushed for rabies testing. Unfortunately, it turns out that rabies testing was not possible. The beaver was killed with a crowbar and "The skull was crushed to the point where there wasn't enough brain material" for testing.
That creates a difficult situation. The likelihood that the beaver had rabies is probably very slim, but rabies is an almost invariably fatal disease. Post-exposure treatment consists of an injection of anti-rabies antibodies and then a series of 4-5 vaccines. It's not fun, but it's not typically that big of a deal (particularly compared to the old protocol from decades past). It's also expensive, which can be a problem if the government or insurance doesn't cover it. I'd certainly err on the side of caution and get my child vaccinated (been there, done that) but there's no word what was done in this situation.
Inadequate brain material for testing occurs occasionally based on how a potentially rabid animal is killed. If you are in such a situation and you can avoid destroying the head, try to do so. But, while keeping the head intact when beating off an attacking animal is the goal from a rabies diagnosis standpoint, you can see how it wouldn't be high on the priority list when actually confronted with an attacking animal.
More information about rabies can be found on the Worms & Germs Resources page.
A five-year-old Oklahoma boy is recovering after being attacked by a beaver. Beaver and attack aren't two words that you usually put together, but in this case the boy went to pet a 60 lb beaver that he saw outside and it proceeded to attack him, taking a "chunk out of his calf" in the process. The beaver was killed with a crowbar.
This is a pretty unusual situation. Beavers aren't known for attacking people, which should raise some red flags right there. Rabies should be considered in any mammal that acts abnormally. An aggressive act by a species not known for unprovoked attacks would certainly count.
The boy's mother went to "great lengths" to get the beaver tested for rabies. I'm not sure why great lengths were required since this was a bite from an abnormally-behaving wild animal in a rabies endemic area, but it's great that she was aware of the problem and acted accordingly. While the outcome was unfortunate for the beaver, the family is lucky that the beaver was killed and available for testing. If it had gotten away, they would have had to assume that it was rabid, meaning the child would need rabies post-exposure treatment. That's expensive and somewhat unpleasant (two initial shots and 3-4 boosters) but virtually 100% effective at preventing rabies (and since rabies is almost always fatal, it's a necessary procedure).
This report highlights a two key points:
- Leave wildlife alone.
- If you are bitten by a wild animal, make sure rabies is considered. It's very rare but fatal when it occurs, so you don't want to take any chances.
If an unvaccinated person is exposed to rabies (usually by a bite), they undergo post-exposure prophylaxis (PEP), consisting of an injection of anti-rabies antibodies and a series of 4 or 5 vaccines. (It used to be 5, but it was recently recommended to drop this to 4). This is a highly effective protocol which basically guarantees that the person won't get rabies IF the person is treated promptly.
If an unvaccinated pet is exposed to rabies, the situation is much different. The two options are euthanasia or a strict six month quarantine and a single dose of rabies vaccine either immediately or after 5 (of 6) months of quarantine.
So, if there is a post-exposure treatment for people that is basically 100% effective, why don't we do the same thing in dogs and cats?
There are a few possible explanations for this:
1) Rabies is almost invariably fatal. The significant public health risks take precedence over animal health and pet owner inconvenience, stress and pet loss.
2) There is limited information about PEP in dogs, and results have been mixed.
- In one study (Hanlon et al 2002), experimentally-infected dogs were treated with various protocols. Treatment with rabies antibodies on day 0, followed by vaccination on days 0, 3, 7, 14 and 35 was effective at preventing rabies in 5/5 dogs - a good result, but the small number of dogs tested (5) prevents us from drawing any broader definitive conclusions. Rabies antibodies alone protected 4/5 dogs. All dogs that did not receive the antibodies but were vaccinated on days 0, 3, 7, 14 and 35 died of rabies.
- In another study (Manickam et al 2008), all exposed dogs were protected by rabies vaccination on days 0, 3, 7, 14 and 28. A 3-dose regimen (days 0, 5 and 28) was protective with one vaccine but not another.
Clearly, based on the limited number and small size of these studies, and the differing results, we cannot recommend a canine PEP protocol with confidence. However, these studies strongly suggest that PEP can be effective in dogs, and I think we need to consider when and how to use it. I wouldn't necessarily use PEP to replace quarantine without more evidence (i.e. field studies). I think the use of PEP to help protect the dogs while maintaining quarantine to protect the public is a good start. If canine PEP can be shown to be as effective as PEP in people, then some day quarantine might not be needed.
Regardless, this situation highlights the need for current vaccination of all dogs and cats in rabies-endemic areas. If a vaccinated animal is exposed to rabies, there is no requirement for euthanasia or long, strict quarantine. Rather, standard guidelines recommend giving the pet a rabies vaccine (booster) and having the animal observed by their owner for a period of 45 days. Developing better PEP protocols for unvaccinated animals is useful, but I'd prefer to see it become a moot point as a result of high vaccination rates.
A large number of rabies cases in Santa Cruz County, Arizona has lead to the rare practice of implementing a county-wide rabies quarantine. Fifty-four cases of rabies have been diagnosed so far this year, mainly in skunks. That's about twice as many as normal.
Quarantine is probably not the best description of what they are doing, but they are taking measures to improve vaccination of pets, reduce roaming pets and discourage human-wildlife interaction.
For the next 60 days, the following rules are in place:
- Dogs and cats must be vaccinated against rabies.
- Dogs must be confined to the property or on a leash.
- People are not allowed to feed wild animals.
- Pet food must not be left outdoors after sundown.
Those are all pretty standard measures that should be used anytime. It sounds like these rules already exist in Santa Cruz County but their "quarantine" means that they will be aggressive in enforcing them. Increasing enforcement is a good idea, but ongoing efforts after this quarantine period are also needed because rabies will continue to be a risk in that area.
Image source: www.acmeanimalremoval.com
Rabies baiting is a highly effective way to reduce rabies in wildlife populations. As we've discussed before, in Ontario this involves air-dropping edible rabies vaccine. These baits are dropped in key rural areas, but there is the potential for curious people to come into contact with the vaccine if they handle baits that they come across. It is recommended that people avoid contact with the baits and wash their hands if they do come into contact with one, because the baits contain a live virus. They do NOT contain live rabies virus. Rather, they contain a vaccinia virus that has been manufactured to produce immunity to rabies virus. The risk of human infection is low, but as we constantly get reminded with infectious diseases, low doesn't mean zero.
Today's MMWR reported a case of human vaccinia infection associated with a rabies bait. In August, a 35-year-old Pennsylvania woman was picking berries and her dog and found a rabies bait. The dog punctured the bait packaging and the woman subsequently handled the bait. It took around 30 minutes for the woman to reach somewhere she could wash her hands, which she then did. This person had a few factors that put her at higher risk of developing an infection, including some skin lesions on her hands from berry thorns, and she was on multiple immunosuppressive drugs.
The day after exposure, her doctor took blood samples for rabies and vaccinia virus antibodies and examined her hands. Skin lesions (papules, i.e. little bumps) developed three days later. These lesions were tested and vaccinia virus was found in them. The skin lesions progressed and she was hospitalized a couple of days later. She was treated with antibodies against vaccinia virus because of the progression of disease and her compromised immune system. She went on to develop muscle aches, headache and a swollen lymph node. She was treated with more antibodies and an experimental antiviral drug. She ultimately responded to treatment and was discharged from the hospital on day 19.
This is the second reported human infection associated with a rabies bait. Considering the millions of baits that have been dropped and the presumably relatively large number of people that have had some contact with the baits, the overall risk of disease is still very low. This person was at high risk because of her immunocompromised status, and it's likely that an otherwise healthy person would not have developed an infection like she did. The big problem here was her contact with the bait. She did everything right after that: washed her hands as soon as she could, called the Department of Health, went to her physician and ensured that testing was done, but she still got sick.
Avoid rabies baits. The risks are low but why take any risk? People that have compromised immune systems or skin diseases should take particular care. If you've been exposed to a rabies bait, wash your hands ASAP and contact the local health authorities to determine if anything else should be done.
An Indiana woman has died of rabies. Little information is currently available. Reports state that bat rabies was involved but that the source of exposure was not known. Presumably, they have determined that she was infected by the bat rabies variant (strain), but she didn't report being bitten or otherwise exposed to a bat. Bat rabies is a serious concern because it is easy to get bitten by a bat and not know it. Most cases of rabies in Canada and the US are associated with bat exposure. This is a tragic reminder about why we pay a lot of attention to bats and rabies (and why my family received post-exposure treatment after having a bat in the house a few years ago).
More information about rabies can be found on the Worms & Germs Resources page.
Here's a recent question: "Can a rabies virus get into the body if you pick up a dead animal the roadway and have a cut on your hand? I understand the animal has to carry the rabies virus but sometimes we don't know what killed the animal. It may be infected and didn't use due diligence or perhaps it just wasn't fast enough. After reading stories here I'm less likely to remove a dead animal. Sometimes they are so juicy, the fluids are flung about and you may get some on your clothes or skin and not know it. How likely is contracting rabies from fluids in a cut? The reason I ask is when I was younger I picked up a dead squirrel with my bare hands and then noticed I had cuts on my hands. I went to a doctor who looked at me like I was crazy but I had that uneasy feeling because I knew rabies is almost always fatal. Of course, I didn't get it but when I watch other people remove dead animals from roadways I cringe. I can't even think about eating roadkill or skinning it for the fur but that's just me."
Good question. You've covered most of the important aspects of risk, which are pretty minimal:
- Animal has to be infected
- Live rabies virus needs to be present
- Rabies virus needs to get into a person's body (not just on it)
Let's look at these individually.
Animal needs to be infected
- You never know whether this is a concern when you find a dead animal. Once it's dead, you can't tell if it's acting strange. In general, it's safest to assume that all such animals are infectious until proven otherwise.
Live rabies virus needs to be present
- I haven't come across good information about how long rabies virus can survive in a dead body outdoors. It probably varies greatly between different situations, particularly depending on the temperature of the body. For very fresh roadkill, there's certainly a possibility that live virus is still present (if the animal had rabies).
Rabies virus needs to get into a person's body (not just on it)
- Rabies cannot be transmitted through intact skin. Rabies infection is transmitted mainly through bites, cuts and scrapes. Saliva or nervous system (e.g. brain) tissue are infectious. Blood, urine and feces are not.
- If you have contact with a dead animal, avoid any direct contact with your skin, and avoid any activities that could result in splashing of fluids. Transmission of rabies from infected fluids is possible if it comes in contact with broken skin or mucous membranes like the eyes or mouth.
- If intact skin has been contaminated with fluid, wash it thoroughly with soap and water, but don't panic - it's really of minimal concern.
- If your clothes have been contaminated with fluid, take them off right away if possible. If that's not practical (or legal), take them off as soon as you get home. Put them in the laundry immediately and wash your hands.
- If open sores or other broken skin has been contaminated, wash the area thoroughly with copious amounts of soap and water under moderate pressure. Disinfectants can be used to help clean the wound, but there's no consensus about whether that's necessary - these chemicals can be painful to use and hard on tissue, and the flushing action of the water probably does the most to remove the virus from the area. You should go to a physician, who will get in touch with public health personnel to determine if there is any reason for post-exposure treatment. If the animal's body is available to test, that's useful. If the brain has decayed too much to be tested properly, it's questionable whether live rabies virus would still be present even if the animal had rabies. Public health personnel will decide whether they think there is any risk.
Bottom line: the risk of contracting rabies from roadkill is very low. Roadkill contact has never, to my knowledge, been identified as a source of infection. Rabies transmission from dead animals has been documented, however, such as a couple cases of rabies from people preparing dead animals for food.
So, if you see a dead animal by the road, leave it alone. If you are going (for some reason) to touch it, first make sure it's really dead. An injured animal might be much more likely to bite. If it's really dead and you are just trying to move it off the road, use a stick, shovel or something else that doesn't involve you having direct contact with the animal. Other than that, I'm not sure why anyone would want to touch roadkill.
A study in the Journal of the American Veterinary Medical Association (Murray et al 2009) investigated the rabies vaccination history of dogs and cats diagnosed with rabies in 21 US states between 1997 and 2001.
- 264 rabid dogs and 840 rabid cats were identified.
- 4.9% of rabid dogs and 2.6% of rabid cats had a history of rabies vaccination.
- Of the 13 dogs that had been vaccinated, only 2 were considered currently vaccinated. Similarly, of the 22 previously vaccinated cats, only 3 were currently vaccinated.
- Texas had the most positive dogs while Pennsylvania had the most positive cats.
This study cannot determine how effective vaccination is. You'd need to know the number of animals that were and were not vaccinated, and then the number that did or didn't get rabies to determine efficacy. The fact that a small number of properly vaccinated animals got rabies shows the vaccine is not 100% protective, which is not surprising.
Vaccination is an important part of rabies prevention, but it's not the only part. Vaccination is a last line of defense - avoiding exposure to rabies is the critical first line. To reduce the risk of rabies exposure, keep your pets under your control at all times. Keep bats out of the house and try to ensure that your house and yard are not welcoming to wild animals. Don't let your pets have contact with wildlife and pay close attention when strangely-acting wildlife are around. Active measures to reduce wildlife rabies such as rabies baiting are also important.
Don't assume because your pet is vaccinated that you don't have to worry about trying to reduce the risk of exposure to rabies.
Don't assume that an animal with neurological disease doesn't have rabies just because it's been vaccinated.
Recently, a relative was bitten by a dog, and the incident emphasized that you need to take such things seriously and pay attention to making sure things get taken care of properly.
So what should you do if you've been bitten?
1) Identify the dog.
- You need to know who the dog is, and who owns it. If you can't identify the dog, you have to assume it's rabid (even though it's extremely unlikely) and get treated with a series of vaccinations.
2) Get medical care as needed.
- Bites can be associated with significant trauma and risk of infection. Getting to a doctor is particularly important if the bite is severe, occurs at a high risk body site (e.g. over the hands, joints, tendons and nerves, groin, prosthetic devices) or if you are at higher risk of infection (e.g. immunocompromised, don't have a functional spleen, very young or very old, pregnant). If in doubt, go to a doctor to be on the safe side.
Once you've done this, it's important to make sure that the offending dog actually doesn't have rabies. If you go to a doctor, they will (in most regions) report the bite directly to public health. Public health inspectors will investigate the rabies vaccination status of the animal and ensure that it is quarantined for 10 days. If the dog has rabies and is infectious, it will develop signs of infection within this 10 day period. If the dog is healthy after 10 days, it did not have rabies at the time of the bite.
Seems pretty simple, eh?
Unfortunately, there are a few places where this process can break down.
Reporting: All bites need to be reported. Bites that do not result in people going to the hospital may be missed. You don't need a serious bite to contract rabies (or another serious infection).
Public health follow-up: This is hopefully not an issue, but you should make sure that public health has investigated, and done so promptly. Don't be afraid to call to find out the status of the investigation, and make sure information has flowed quickly from the physician to a public health inspector. Hopefully they'll be in touch with you, but don't be afraid to initiate contact. The main issue with follow-up relates to the next point:
Prompt euthanasia of the dog: Sometimes, people will decide to euthanize a dog after a bite, because it's done it before, because they consider any bite unacceptable, and/or they fear for family members or legal liability. Dogs (or cats) that have bitten someone must not be euthanized before the 10 day quarantine period is over. If the dog is euthanized and the body is not available for testing, you have to consider the dog rabid and undergo post-exposure treatment. Veterinarians are required to ask whether a dog has bitten someone in the preceding 10 days prior to performing euthanasia, but it's possible that this could be missed, or people may not tell the truth because they want to have the dog put down ASAP. This is why public health inspectors need to investigate promptly - to provide another level of assurance that the animal is not euthanized inappropriately. You should follow up with public health to make sure things are underway and the dog is quarantined.
Rabies associated with dog bites is extremely rare in Canada (and many other countries) but still kills tens of thousands of people every year, mainly in Asia and the Middle East. Considering it's almost invariably fatal and pretty much 100% preventable, you need to pay attention to the risks, no matter how small.
A rabies epidemic continues in Bali, with little apparent control and inadequate access to vaccination. Another person died of rabies last week. He was bitten by a dog in July and taken to a local health centre, but rabies vaccine was not administered. It's not clear whether healthcare providers recommended post-exposure vaccination and the person declined or whether they did not offer vaccination.
Access to post-exposure treatment in such regions is a serous concern. Apparently, up to 50 people a day are denied potentially life-saving post-exposure treatment because of a lack of adequate vaccine supplies. Because of the limited availability, doctors are focusing on treatment of people bitten by dogs in areas that are heavily infected with rabies. That makes complete sense, but it's still not a good situation. It's not only those heavily infected areas that are a concern. More rabies vaccine needs to be secured so that everyone who has been potentially exposed can be properly treated. Local officials are blaming the current shortage on a holiday weekend, but it's unclear whether the situation is truly going to improve in the near future.
People traveling to any part of Bali need to be aware of the risks. You don't need to cancel your vacation, just use common sense. Don't approach any dogs or other mammalian pets or wildlife. If you are bitten, immediately go a physician. If rabies vaccination is not offered, ask for it. If it's not given, get on the next plane out of the country and get treated. You don't need to be vaccinated immediately after exposure, so don't panic, but you don't want to unnecessarily increase the risks if you have been bitten.
This comic, based on actual (and unfortunately common) events, was developed by Los Angeles County Veterinary Public Health. It's a good example of novel ways of communication regarding zoonotic diseases. More information from Los Angeles County Veterinary Public Health (and apparently future editions of Rabies Tales) can be found on their website.
In April, I wrote about an ongoing rabies outbreak in the popular tourist destination of Bali. Because of widespread rabies in stray dogs and fatal human infections, there were calls for the government to take aggressive action and for tourists to be aware of the risk. Apparently, things haven't improved much since then.
At least 9 people have died of rabies in Bali in slightly over a year. That's completely unacceptable for a preventable disease.
The latest victim (whose father-in-law died of rabies in August) was from an area that has not been officially declared as being part of the epidemic, so it has not received much government support. She was bitten by a stray dog in August. In any rabies-endemic area (even in the absence of an outbreak), that's clearly an indication for post-exposure treatment. However, she did not receive post-exposure treatment until 15 days after the bite, by which point it was obviously ineffective.
- Rabies post-exposure treatment must be started as soon as possible. If you wait until signs of rabies are present, death is almost certain.
- Be informed and be your own advocate. The family in this case may very well have pushed for post-exposure treatment, but it's critical to look out for yourself. If you have potentially been exposed to rabies, make sure you get treated.
- If you are going to Bali, don't be paranoid about rabies. Be smart. Avoid any contact with dogs (especially strays) and other wildlife. If you are bitten, get medical care immediately. If the animal isn't identified and quarantined for 10 days to make sure it doesn't have signs of rabies, you need post-exposure treatment. If you can't get it in Bali, get out and get to somewhere where you can be properly treated.
- If you are traveling to Bali (or any other rabies-endemic area) with the intention of working with wild or stray animals (especially dogs), get vaccinated before you go.
- More aggressive rabies control and education (including physician education) efforts are needed in Bali. Clearly, this outbreak is not under control and the fact that the latest death occurred in a new region suggests that this problem could be spreading.
More information about rabies can be found on the Worms & Germs Resources page.
A Montreal man is undergoing rabies post-exposure treatment after being bitten by a bat in Lachine's Summerlea Park. He found the bat lying on the ground and when he picked it up to take a closer look (surprise, surprise) the bat bit him.
This incident shows yet again the need for better rabies education. While we don't want to create fear and loathing of bats, we should consider them rabies-positive until proven otherwise. That doesn't mean we want to eradicate them. It means we want to educate people to enjoy them from a distance and never have direct contact with them.
Never try to touch a bat. A bat lying on the ground in a park is not a healthy bat. It may be sick for various reasons, but rabies is certainly a possibility. If you come across a sick bat, call animal control. They can safely remove it so that no one has the chance of being bitten. If someone has had contact with the animal, the bat must be tested for rabies, as was done here. Rabies is preventable using proper post-exposure treatment, but it's very expensive, a hassle and a series of vaccine's isnt' exactly fun.
As a vet, I've been bitten by a wide range of animal species. When people talk about animal bites, they usually think about dogs and cats. Horses can (and do) bite as well. Most horse bites are probably playful nips that hurt a little yet don't cause major problems, but some bites can cause serious injuries and infections can result.
A recent paper in the Journal of Agromedicine (Langley and Morris 2009), with the rather unwieldy title of "That Horse Bit Me: Zoonotic Infections of Equines to Consider after Exposure Through the Bite or the Oral/Nasal Secretions". Bites apparently account for 3-4.5% of the approximately 100 000 annual emergency room visits in the US that are associated with horses. The authors of the paper review infections associated with bites and contact with organisms in the mouth and nose of horses.
A large number of bacteria have been associated with horse bite infections in people, including Actinobacillus, Streptococcus, Psuedomonas and Staphylococcus species. Some viruses can theoretically be transmitted by bites, but there's little evidence that this actually happens.
Although viruses are not of as much of a concern overall, rabies needs to be considered in every bite from a mammal. We pay a lot of attention to rabies with dogs, cats and wildlife, but it often gets ignored with horses. While I'm not aware of any reports of rabies transmission from horses to humans by a bite, it could happen. Fortunately, rabies is rare in horses so the likelihood of exposure from this species is very low. However signs of rabies aren't always obvious initially, and rabies in horses may mimic other diseases. Sometimes, rabies looks like colic, and human exposure through bites or other contact is possible when handling, evaluating and treating affected horses.
Unlike with dogs and cats, there are no clearly defined protocols for dealing with bites from horses. Any dog or cat that bites a person is supposed to be quarantined for 10 days. The reason for this is if the animal is rabid and the disease is advanced enough for the animal to be capable of spreading rabies virus, it would invariably develop signs of rabies and die within this time period. We don't have similar guidelines for horses. I suspect the 10 day observation period would be adequate but we don't have good data. The paper states that in Kentucky, a 14 day observation period has been used by the state Department of Public Health.
At the conclusion of the paper, the authors make a few important general recommendations for reducing the risk of disease transmission from bites and oral or nasal secretions of horses:
- Use good general hygiene, especially hand hygiene, after any contact with horses.
- Use gloves and gown or lab coat when examining horses in a veterinary clinic or hospital. (This might be overkill for all horses. We don't require gloves for every horse contact, just contact with mucous membranes (e.g. mouth, nose), wounds, incision sites and other high-risk areas. I think bare hands are fine for general contact as long as there is good attention to handwashing after.)
- Consider mask and goggles if the horse is coughing or sneezing.
- Develop standard operating procedures for handling sick horses.
- Use isolation when needed.
I'd add a few more points:
- Avoid bites. Pay attention to what you are doing around horses to reduce the risk of being bitten. Do not encourage playful behaviours (e.g. nipping) that could lead to bites.
- If you are bitten and it breaks the skin, clean the site thoroughly with soap and water. If there is significant trauma, or if the bite is over a joint, hand, foot, or a prosthetic device, you should see a doctor immediately because antibiotics are most likely indicated. If you have a weakened immune system, you should be evaluated by a doctor after any bite.
- Avoid contact with the horse's mouth or nose if you have skin lesions. Cuts and scrapes can allow bacteria to enter your body and cause infections. If you have a cut on your hand, make sure it is covered with a glove or waterproof dressing if you are going to have contact with the horse's mouth or something that came from its mouth (e.g. a bit).
This Worms & Germs blog entry was originally posted on equIDblog on 02-Sep-09.
In response to recent problems with attacks by stray cats and concerns about rabies exposure, Point Pleasant Beach, New Jersey, is planning to round up all the stray cats they can catch. Cats will be monitored in rented trailers for 60 days, and any cats that do not have signs of rabies will be adopted out (after being vaccinated and spayed/neutered). It's perhaps overly optimistic that all cats will be adoptable, since not all strays (especially older cats) are going to be appropriate for household pets, but they will hopefully find good homes for many of these cats.
While this program could be beneficial in some ways, let's hope a lot of thought has been put into it. This type of mass roundup and confinement is quite likely going to result in high transmission of many infectious diseases that circulate in the stray cat population. Hopefully there are plans for proper initial health assessment of captured cats, isolation of cats showing signs of infectious disease, cohorting of different groups to reduce the risk of disease transmission and use of good general infection control practices. Without these, they are asking for major problems. Unfortunately, infection control is often not considered in situations like this until a major disease outbreak is already underway.
The 60 day quarantine period may raise questions, but it's a reasonable approach. If they were doing a formal rabies quarantine, it would be six months. The maximum incubation period for rabies in cats is not known, but it can be very long in humans in rare instances. Realistically, 60 days is a pretty good quarantine period under these circumstances. You can't be 100% certain that an animal isn't incubating rabies after 60 days, but it becomes very unlikely and I wouldn't be concerned after 60 days. Sixty days is also a good amount of time to identify (and hopefully address) any other major health issues.
Another issue that needs to be considered is ongoing population control efforts such as continued catching and adopting of strays, catching and neutering strays, and educational efforts to encourage people to have their cats spayed or neutered and discourage them from feeding strays. A lot of time and money can be put into a big one-time effort, but this town might end up in exactly the same stray cat situation in a year or two if nothing else is done.
Rabies baiting is a common and effective way of controlling rabies in some wildlife populations, particularly skunks, raccoons and foxes. It involves dropping edible rabies vaccine, by airplane or by hand, into targeted areas. Millions of rabies baits are used across North America and baiting programs have been cited as a key aspect of wildlife rabies control. In one year, 1.3 million baits were dropped in targeted areas of Southern Ontario alone over a two-month period. A good series of pictures of rabies baiting is available here.
Rabies baits are usually a small rectangular block comprised of something that smells or tastes attractive to the targeted wildlife into which a liquid vaccine has been added. Some use fish meal and fish oil to attract wildlife. Others use combinations of fats, icing sugar, vegetable oil and artificial marshmallow flavour (don't ask me why - I'm certain there's a reason but I don't know if they've done taste-testing).
Often, the local public is notified in advance of the drops being made, and it is recommended that kids be closely supervised outdoors for a week or so to ensure they don't come into contact with the baits. It is also often recommended to keep pets indoors or on leash during the same period. (Pets are much more likely to be exposed to and to eat the vaccine than kids). It's also recommended that you wash your hands thoroughly if you have contact with a bait.
Rabies baits are quite safe, and these recommendations shouldn't cause concern. It's a case of being overly cautious. The baits are safe to touch, but it is still recommended that you don't touch them (if nothing else, they may make your hands smell pretty bad). Ingestion of a rabies bait by a person or pet is also unlikely to cause a problem. Any adverse affects are more likely to occur due to the non-vaccine component of the bait, particularly because of the typically high fat content. Ingestion of a lot of baits could certainly cause vomiting or diarrhea in a dog, just like ingestion of large amounts of other inappropriate foods.
Some groups recommend that you contact Poison Control if your pet has been exposed to a bait, but I'm not sure what they'd do in such a case. Other groups ask you to report to them that a pet ingested the bait, likely so they can consider exposure of people and pets when determining target areas for the next year. There's similar variation in recommendations if a person ingests the vaccine. Often it is recommended that public health be notified so they can record it, but it's very unlikely anything would be done.
On a related note, you cannot use rabies baits as a free way to vaccinate your pet. It might work, but there is no way to know, and if your pet is exposed, it would be considered unvaccinated if it was not properly vaccinated by a veterinarian with an appropriate dog/cat vaccine.
Clallam County (Washington) is considering dropping the requirement that pets be vaccinated against rabies in order to get a license. It's pretty clear that this is only based on a desire to get more people to pay for licenses. Sheriff Bill Benedict is quoted as saying "My view on this is, we're leaving money on the table by not finding a way to get more people buying licenses."
This money-driven mindset makes no sense, and raises the question "what is the purpose of licensing pet?" Is it only to provide a source of government income (in other words, a tax on pet ownership), or is it for greater purposes such as helping protect the pet and human population?
Another quote from Benedict: "You would still be required to have your pet vaccinated, but that would be more of an issue between the pet owner and the veterinarian." This isn't an issue solely between the pet owner and the veterinarian. Rabies vaccination is still required by law. Veterinarians do not have a mandate or power to require vaccination and enforce the law. With this "You still need have your pet vaccinated (wink, wink, nod, nod)" approach, the municipal government is essentially saying, "We really just want you to pay us for a license. We don't really care whether your pet is vaccinated against rabies or not as long as you give us money."
A local veterinarian wrote to the commission that "Licensing pets is sometimes the only reason an owner will get rabies vaccines... Rabies vaccinance is the law of the state, the law of the county. Licensing, in my view, is less important than vaccinating for rabies and may facilitate even more rabies cases."
Well said. The county may get more money because more people will get licenses, but it's certainly possible that fewer pets will get vaccinated. Just one rabies exposure could negate the increased revenue from more licenses based on the high costs of rabies post-exposure treatment (let alone the risk of disease, stress of exposure, costs required for investigating cases...). Since all those costs would come from other peoples' budgets, however, I doubt they're too concerned.
Benedict also stated "Most pet owners -- in fact the vast majority -- if they're responsible enough to get a license, they're responsible enough to get a pet vaccinated."
Good thing he's not a lawyer. It seems to me that he just shot his argument down. If the majority of pet owners that are responsible enough to get a license are also responsible enough to get a pet vaccinated, then why is this change required? An attempt to increase cashflow is not a good reason to change rules that are designed to protect the public and pets from a fatal disease.
A horse in Harford county Maryland has been euthanized because of rabies. The horse first starting showing signs of disease in mid-July, which manifested as "striking changes in behaviour." The report doesn't say when the horse died, but animals typically die within a few days of the onset of neurological disease. The horse was transferred to the New Bolton Center where rabies was diagnosed. Subsequent testing showed it was a raccoon rabies strain, although that does not mean that a raccoon was the actual source of infection.
Public health officials implemented a 45 day quarantine of the farm. Stray cats (about 25) were caught and euthanized. Fortunately, the family pets were properly vaccinated and have received booster shots (plus presumably a period of observation at home... a much better situation than if they were not vaccinated).
People that had contact with the horse have received rabies post-exposure treatment. This includes one person who had to be tracked down overseas.
Harford County Health Department spokesperson Bill Wiseman said "There was never a risk to public safety. This incident was a great example of public health work in action and cooperation between local, state and in this case, international authorities." I don't buy the statement that there was no risk to public health. While the risk of rabies transmission from infected horses is very low, it's not zero. Rabid horses have killed people because of their abnormal and sometimes aggressive behaviour. Further, the fact that this horse had rabies means that it got it from something. Rabies can have a long incubation period so it's not guaranteed that it acquired it on the farm, but you have to be prudent and assume that there is infected wildlife in the area that could pose a risk for other animals or people. Public health authorities managed the situation well and reduced the public health risks, but there were certainly still risks.
Rabies vaccination is highly effective. There is no statement about whether this horse was adequately vaccinated but it's unlikely. Proper vaccination would likely have prevented this horse's death, as well as the death of the stray animals, cost of vaccination of people, cost of veterinary care for this horse, quarantine of the farm and the associated financial and emotional costs. A dose of vaccine that costs a few dollars could have saved thousands of dollars and emotional stress.
Rabies is a rare disease in horses but its severity means it should not be ingored. Vaccinate your horses.
This Worms & Germs blog entry was originally posted on equIDblog on 14-Aug-09.
State public health officials are trying to get the word out about a potential rabies exposure in Annapolis, Maryland. A rabid kitten was discovered outside a Sears store at the Westfield Annapolis shopper center. The concern is that people may have handled the kitten and been exposed. It's a major concern with kittens because they can be hard to resist - a pathetic-looking/cute little kitten sitting around in a public place could easily be picked up by many people. Also, when rabies is found in a young kitten, there are often other rabid kittens from the same litter in the area. Rabid stray kittens have caused widespread exposure in the past, and this case may be no different.
Anyone who recently had contact with a stray kitten in the area in question should contact public health officials as soon as possible. Simply touching the kitten is not a rabies exposure risk, but anyone that has had any contact with a potentially rabid animal should talk to public health officials to determine whether there is any risk of infection and whether post-exposure treatment is required.
While kittens are hard to resist, avoid handling stray kittens. This is especially true if it's transient handling where you will never know what happened to the kitten afterwards (as opposed to someone adopting a kitten off the street - this is still risky from some standpoints, but at least you know if the kitten gets sick and you can make sure that it is tested for rabies or other other zoontic diseses, if need be).
If a groundhog sees its shadow, there's more winter on the way. If it doesn't see its shadow, spring is coming soon. So what does it mean when a groundhog attacks a cop?
An aggressive groundhog in New Jersey that tried to attack two police officers and one other person was confirmed to have rabies. Police were called to a house because the groundhog in the garage charged the house owner as he tried to get into his truck. The groundhog was subdued with pepper spray (I wonder if anyone has every used a Taser on a groundhog), caught, euthanized and tested for rabies. Fortunately, none of the people came in direct contact with the animal, therefore there was no exposure and rabies post-exposure prophylaxis was not required.
Groundhogs are not high on the list of animals that tend to get rabies. One-hundred twenty-three rabid groundhogs have been identified in the state since 1989 (I'm actually surprised it's that high), compared to 4 175 raccoons. Like every other mammal, groundhogs are susceptible to rabies virus but they are less likely to carry the virus, because they are rather shy vegetarians and would often not survive attacks from rabid predators. This case is a good reminder that rabies must be considered in any animal acting strangely.
A stray cat taken by someone to a family gathering in Delaware, USA, resulted in 17 people from 4 states undergoing rabies post-exposure treatment. The kitten was found by the side of the road, taken to the gathering (it's unclear whether it was found on the way there or earlier), and when it became ill after the gathering, it was diagnosed with rabies. This is just one example of the potential for widespread exposure of people handling stray (or recently stray) animals at events like reunions, flea markets and sports tournaments. Because these animals (especially cute little ones like kittens) often get handled by a lot of people, a lot of people can be exposed to rabies if the animals are carrying the virus. These situations create major problems for public health personnel, because it's difficult to identify all the individuals who were potentially exposed when they are dispersed across the country.
While generally uncommon, this type of scenario happens a few times a year.
- Don't bring stray, or recently adopted, animals to public events.
- Ensure that your animals are properly vaccinated against rabies. Animals that have not been properly vaccinated should not be taken to public events.
- Don't handle stray animals.
- If an animal that you have recently adopted gets sick, make sure rabies is considered and, if necessary, make sure the animal gets tested.
In Canada, access to rabies vaccine for animals is restricted to veterinarians (i.e. only vets can buy the product itself and administer it to people's animals). In general, this is an excellent approach because it ensures that the vaccine has been handled and stored appropriately, animals have been vaccinated properly and accurate vaccination records are kept. I certainly wouldn't want rabies vaccine freely available, whereby anyone could buy vaccine, handle it poorly, vaccinate their animal improperly, and yet believe or claim to have a properly vaccinated pet.
The problem with this restriction is the fact that veterinary care is not always available. Specifically, I'm referring remote northern communities that do not have veterinary care on a regular or even a sporadic basis. I received an e-mail the other day from a medical professional in a fly-in First Nations community in Northern Ontario. They have not had a visit from a vet in a while, so the dogs there aren't vaccinated. Unfortunately, a dog was attacked by a wolf recently so it must be considered possibly exposed to rabies, resulting in euthanasia or long quarantine. The question was about what can be done in those communities to provide rabies vaccine for people's animals. I didn't know, so I inquired with the Canadian Food Inspection Agency, the federal agency in charge of all-things-rabies.
There are actually provisions in Canadian regulations for situations like this (a provision in the Health of Animals Regulations Section 132.4 (2), if you want to know specifically). This allows rabies vaccine to be sold in accordance with written permission granted by the Minister, in specific circumstances such as in a remote area where veterinary services are not readily available. The provincial veterinary association is typically contacted to determine whether or not there is a veterinarian who could arrange to do the vaccinations. If the provincial association agrees that there is no veterinary service available to the community, then permission can be granted to purchase vaccine.
It's quite a reasonable and logical approach that allows for access to rabies vaccine when needed, but has enough controls in place to ensure that this can't lead to abuse of the exception. People in remote communities in Canada should be aware of this. Some communities get periodic visits from vets but there are many others such as the one in this case that don't have any direct access to veterinary care, and this is a way of at least providing protection for people and pets against rabies.
Two kids and one adult are undergoing post-exposure treatment for rabies after having contact with an infected kitten. One child saw the stray animal and went to give it some food, and he was bitten in the process. The kitten then proceeded to bite the boy's mother and another child in the neighbourhood. Fortunately, the kitten was taken to animal control and was identified as a rabies suspect. It was euthanized and testing of the brain confirmed it had rabies. Accordingly, the three bitten people are now undergoing post-exposure treatment. Animal control is handing out flyers in the neighbourhood to warn others, as there may be more rabid animals in the area. One particular concern with young kittens is that sometimes multiple animals from the litter are infected, so there may be more cute but deadly kittens in the area.
- Avoid contact with stray animals. That's the best way to avoid getting bitten by one.
- If you are bitten by a stray animal, the animal must be caught and quarantined. If you don't know the rabies status of an animal that has bitten you, you have to consider it rabid and get treated. If you are bitten by a stray or wild animal, call animal control to catch it. If you can safely contain it (e.g. lock it in a garage) without putting other people at risk, do so and then wait for animal control to capture the animal.
- Vaccinate your pets.
There are two situations when animals may be quarantined because of rabies concerns:
- After biting a person.
- After potentially being exposed to a rabid animal.
The time frame for quarantine in these two situations is quite different because of what the quarantine is meant to accomplish.
Animals that have bitten someone are quarantined for 10 days under observation to see if they develop signs of rabies. Most animals that bite do not have rabies, and this is the easiest way of determining whether the animal could have potentially transmitted rabies by way of the bite. If an animal was rabid and infectious at the time of biting, it would die from the disease within 10 days. Animals can only transmit rabies virus after it has reached the brain and started to spread outwards via nerves - it gets into saliva by working its way down nerves from the brain to the salivary glands. Once an animal gets to that stage of disease, they die quickly. So, if the animal is still alive after 10 days, it was not rabid at the time of the bite. Quarantine is important so that it can be clearly proven one way or the other whether the animal was rabid. If the biting animal was not quarantined and ran away, the recommendation would be to err on the side of caution and treat anyone bitten as if they'd been exposed... but we want to avoid that if at all possible.
The second type of quarantine (for a potentially exposed animal) is based on less solid evidence. The idea in these cases is to keep the potentially exposed animal isolated while waiting to see if it develops signs of rabies, because there is no other reliable test for rabies in a live animal. For example, if an unvaccinated dog gets into a fight with a rabid raccoon, it would be considered potentially exposed. It would be quarantined (or immediately euthanized... the other option) and monitored to see if it develops signs of rabies. The length of quarantine for non-vaccinated dogs is usually 6 months, but this may vary by region. This helps reduce further rabies transmission by ensuring that a dog that develops rabies during the quarantine period is not roaming at large and able to infect people or other animals. One weakness of this approach is the incubation period of rabies, which can be very long. There is not a lot of objective research on which to base the 6 month time frame (unlike the 10 day quarantine described above). After 6 months, it's very unlikely the dog will develop rabies, but we can never say it's 100% because of the rare cases of rabies in humans with extremely long incubation periods. In reality, it's likely that the vast majority of animals that are exposed will develop rabies before 6 months, so it's a reasonable time frame. Would it be better to use 4 or 8 months, or something else? Possibly, we just don't know.
The easiest ways to avoid hassles associated with rabies quarantine are:
- Prevent bites. If your pet is trained and observed properly, it's unlikely to bite anyone, so the 10-day post-bite quarantine shouldn't be an issue.
- Vaccinate your pet. Properly vaccinated pets are not subject to the same long, strict quarantine (although a shorter period of isolation (often at home) is usually still required).
More information about rabies can be found on the Worms & Germs Resources page.
Currently, people that have potentially been exposed to rabies undergo post-exposure treatment consisting of one dose of rabies antibodies followed by a series of 5 vaccinations on days 0, 3, 7, 14 and 28. It's not fun but it's much better than the old horror stories of 14 or more injections in the abdomen, which was the standard until the 1970s. For most people, the series of 5 rabies vaccines is not that big of a deal, but some people have adverse reactions, and having to undergo that many shots is not enjoyable, especially for children.
Now, a US advisory committee has recommended changing the vaccine requirements to 4 doses. There are a couple reasons for this. One is that many people end up skipping the final dose anyway and none have ever come down with rabies (although the strength of this argument is dependent on how many of them were truly exposed and at real risk of disease). Another is the cost of vaccination, which runs $100-200 per dose. When you multiply that by the tens of thousands of people that are treated annually, eliminating a single dose results in pretty big cost savings.
However, it's interesting that this recommendation has been made without coordinating with vaccine makers. Therefore, if this change is adopted, physicians would have to choose between following the US recommendations or the vaccine label. This could lead to confusion as well as legal liability concerns. "Off-label" drug use is a touchy area, and is generally frowned upon. Vaccine manufacturers may be unwilling to change the label because of a lack of scientific evidence clearly indicating that 4 doses are effective, plus the fact that it would instantly reduce sales by 20%. If this guideline is adopted, significant education efforts, assessment of liability and discussions with manufacturers will be needed. If 4 shots are truly effective (which is probably the case) this is probably a good change.
More information about rabies can be found on the Worms & Germs Resources page.
At the same time that the country is drafting an animal welfare law that would ban widespread killing of dogs, a Chinese city has killed 36 000 stray and pet dogs in an effort to eliminate rabies. Since late May 2009, more than 6 000 people in Hanzhong have been bitten or scratched (presumably by dogs), and 12 have died of rabies. Certainly, this indicates multiple problems. One is the massive number of bites and scratches. Contributing factors probably include a large stray animal population, limited routine animal control efforts, and inadequate education of the public regarding bite avoidance. The number of injuries and deaths certainly indicates that an aggressive response is needed. However, there is little evidence that culls (i.e. mass killings of this type) have any effect on controling rabies and animal-associated injuries. Efforts are probably better directed at other forms of population control, vaccination of stray and pet dogs, and education of the public to keep stray dogs away and reduce the risk of bites. These types programs cost money, but the costs of treating 6 000 bites and 12 fatal rabies infections can be enormous. I don't know how many people received post-exposure treatment for rabies, or what such treatment costs in China, but it's estimated to cost about $1500 per person in North America. That would pay for a lot of rabies vaccine for dogs.
Photo: Hanzhong, China (source: www.panoramio.com)
- Parent finds a dead bat carried in by the family cat and, for reasons known only to him/her, puts it in a jar.
- The next day, the parent takes the bat to a school, takes it out of the jar, and presents it to 8 classrooms full of children. Many students, teachers and staff touch the bat.
- The school nurse finds out later that day (I assume this finding is accompanied by a large spike in the nurse's blood pressure), and advises the parent to submit the bat for rabies testing.
- The bat tests positive and an investigation is started.
- 107 students and staff are interviewed and all are identified as requiring rabies post-exposure treatment. One student reported that their finger may have been pricked while sticking it in the bat's mouth, which would be a high risk exposure.
- 74 people ended up being treated. There's no word as to why some declined.
This was clearly a completely avoidable situation that resulted in potential widespread exposure to rabies, a large investigation, stress for people and their families, as well as the expense and pain of multiple injections for many individuals - all because one well-meaning but poorly-informed parent brought a dead wild animal to school, and because none of the teachers or staff that witnessed this thought to act.
The school's insurance policy covered the $75 000 in vaccine costs (plus an additional $29 000 for vaccine that was ordered but not used by people who declined vaccination).
- People need to be more informed about diseases such as rabies. This type of information is available on the Worms & Germs Resources page.
- Schools need to develop and enforce policies regarding visitors and pets. Approximately 1/3 of large scale rabies exposures occur in schools.
- Common sense needs to be a little more common.
A recent question from a reader:
"We live adjacent to the Oak Ridges Moraine in Aurora (Ontario) so our property has always been popular to local wildlife. For years, neighbourhood animals have enjoyed dry cat food in our backyard but the town has ordered this practice must stop immediately. Among reasons given, were that this food is harmful to the animals. This should be appropriate food for stray and feral cats but am writing to enquire if there is any information available about the effect of dry cat food on birds, raccoons and other domestic wildlife. Since the Premier declared Ontario free of the raccoon strain of rabies last year and there have been no recorded cases in York region, the main health concern is likely raccoon roundworm. I understand that incidence is quite rare but, coincidentally, the recent articles about roundworm cases in New York led me to you. Can you recommend sources of information to learn if feeding dry cat food is harmful to wildlife (raccoons) and if this food would cause increased risk of raccoon roundworm in the immediate area."
This raises some very interesting points.
What are the bad points about feeding wildlife?
Wildlife is best kept wild. The more we feed wild animals, the more contact there can be with people. That can be dangerous, depending on the animal (e.g. coyotes). It can also bring disease-carrying wildlife in closer proximity to peoples’ living spaces, such as encouraging roundworm-shedding raccoons to live next to houses. If you feed raccoons and they decide to stay, you may end up with a highly contaminated raccoon latrine somewhere on your property. That could pose a particular risk if you have young children or developmentally delayed individuals at home.
The natural food supply is one of nature’s ways of keeping animal populations at appropriate levels. If lots of people feed wild animals, their numbers can increase, resulting in more exposure to people, increasing animal population density (with corresponding risks to the animals from disease transmission) and an unsustainable population should the "free food" source disappear. It can also have a huge impacts on the local ecosystem of which we may not even be aware. Making wild animals dependent on humans is not a good thing.
Cat food is for cats. Dog food is for dogs. Neither of these necessarily provide appropriate nutrition for a raccoon, because dietary needs are different for each species. That being said, eating small amounts of pet food periodically likely doesn't do any harm to the raccoons. However, if raccoons rely on pet food as their main food source, I wonder whether health problems could develop, because the animals may stop eating the foods they need to provide a balanced diet.
What does "raccoon-rabies free" really mean?
Raccoon rabies is a type of rabies virus (example of other types are bat rabies virus and skunk rabies virus). Raccoons can be infected by other rabies viruses, so even though Ontario may be free of raccoon rabies, the province is not necessarily free of raccoons with rabies. Raccoon rabies control efforts have been highly successful in Ontario, but it is important to be aware that raccoons can still carry rabies. Any feeding practices that encourage contact with raccoons (as well as skunks, foxes and other wildlife) are of concern because these animals can carry rabies, of one type or another.
Cab drivers have to put up with a lot of risks, but attacks from marauding rats probably aren't high on their list of concerns. However, a Ukrainian cab driver was recently attacked by a rat, and the rat was subsequently killed and found to be positive for rabies. The cab driver is now undergoing post-exposure treatment, and authorities are vaccinating pets and trying to eliminate mice and rats in the nearby neighbourhoods.
This is another good example of why it's important not to ignore a bite from any mammal, because rabies can affect any mammal. People often don't consider rodents a concern when it comes to rabies transmission, because most rodents would die from an attack by a rabid animal, thus preventing them from becoming infected and passing on the virus. This is probably true in most circumstances, but there have been enough reports of rabies in rodents, and potential human exposure from contact with rabid rodents, that we have to pay attention to this risk. Overall, the likelihood of acquiring rabies from a rat bite is pretty minuscule, and much less than the risk of contracting other diseases such as rat bite fever, but it's not zero. Since rabies is almost invariably fatal, even seemingly low risk situations need to be carefully assessed. In the case of this cab driver, there was definitely a risk of rabies exposure. If the rat had not been caught and tested, the potential for rabies exposure might have been dismissed, which could have had catastrophic consequences for the cabbie.
More information about rabies can be found on the Worms & Germs Resources page.
Quarantining animals that have potentially been exposed to rabies is a standard practice, but quarantining a whole town is new to me. Because of a large increase in rabies cases in the Flagstaff, Arizona area, a rabies quarantine was established on April 8th by the Coconino County Board of Supervisors. The quarantine requires all dogs and cats to be enclosed or secured on their owner's property. When off the property, animals must be on a leash that is no longer than six feet in length. All dogs and cats must be vaccinated, and low-cost rabies vaccine clinics have been held to help increase compliance with this requirement. Vaccination of wildlife using baits containing an oral form of rabies vaccine will also be performed. The quarantine also restricts feeding and interacting with wildlife. Also, people cannot leave pet food outside after sunset and all compost piles must be completely enclosed.
This is an aggressive approach to rabies control in an area experiencing a wildlife outbreak of the disease. They've implemented comprehensive but still quite practical measures that should help reduce the risk of exposure of domestic animals (and people) without a significant negative impact on pet owners. I've mentioned my concerns about rabies vaccine clinics in the past, but this is a situation where I think it's a good idea.
It's always hard to evaluate the effectiveness of outbreak measures, because you never know what would have happened if nothing had been done. Regardless, it will be interesting to see how well this quarantine works, both in terms of the number of new rabies cases they see and the response of citizens to these restrictions. It would be very useful if Coconino County personnel provide information about how things went when the quarantine is over - the information might be useful for management of future rabies outbreaks.
Rabies vaccination is supposed to be given at regular intervals - typically every 1 or 3 years, depending on the vaccine. Some people don't want to vaccinate their pets on a regular basis, but they may not understand all the implications of this decision. Often, people ask whether antibody levels (titres) can be checked to determine if repeated vaccination is necessary or if it can be delayed longer. However, rabies is covered by very straightforward government regulations in Canada (and presumably in many other regions). According to these regulations, checking vaccine titres is not considered an acceptable alternative to regular vaccination. Knowing this, here are two scenarios to consider:
1) Your pet bites someone.
After a pet bites anyone, it must be monitored for 10 days to ensure that it does not develop signs of rabies. It makes no difference whether the animal is vaccinated or not. However, if you do not have proof that your pet has been properly vaccinated, in Ontario, it is theoretically possible that you could be charged under the Health Protection and Promotion Act.
2) Your pet is exposed to a rabies suspect.
If your pet was vaccinated, you'd have two options. Most commonly, your pet would receive a booster vaccine and would be observed at home for 45 days. Alternatively, if you wanted to avoid a booster, you could take a blood sample to check the rabies titre. If a protective titre (>0.5 IU/ml) was present, there would be a 45 day observation period. If a protective titre was not present, the pet would be treated as unvaccinated.
If your pet was not vaccinated, it would be subject to a strict six-month quarantine or euthanasia.
If your was vaccinated at some point, but not vaccinated according to the vaccine manufacturer's guidelines (i.e. it didn't receive the appropriate 1 or 3 year booster), it would be considered unvaccinated, and be subject to the same 6 month quarantine. It would not matter if the rabies titres had been checked and a protective titre had been present in the past.
From this, it should be clear that there are serious implications of not vaccinating your pet, at least in Canada. There are some circumstances where you may be rightfully hesitant to vaccinate your pet, such as if your pet previously had a severe vaccine reaction. However, if you choose not to vaccinate, you must be aware of the implications of this decision. Neither a letter from your vet stating that vaccination would be risky nor annual rabies titre checks are going to be of any help at all because of the rules that are currently in place.
The British Columbia Centre for Disease Control (BCCDC) has changed its rabies exposure guidelines and gone against established protocols used elsewhere. Typically, anyone who has slept in a house where a bat was present at the same time is considered to have been exposed to rabies if the bat was rabid or the bat's rabies status is not known. This is because bats can bite people while they are sleeping and the bite wounds can be so small that someone may not even notice after they wake up. People who get rabies from a bat bite almost always die. Because of the severity of this disease, the general rule has been to err on the side of caution and consider anyone even possibly bitten by a bat as exposed to rabies.
Yes, rabies is a very rare disease in people in this part of the world... but you don't want to be the rare person that gets it. I understand that risk analysis may indicate that there is, overall, low risk from sleeping in the same house with a bat, and that almost all people that receive post-exposure treatment didn't actually need it. However, for a fatal disease with the potential for uncertain exposure in such a situation, I think this is important to err on the side of caution. It's always difficult to reconcile risk analysis data with human lives. The BCCDC estimates that this new policy will only result in one (1) additional rabies death every 675 years. That's not a lot, but how would you like to be that one person?
I hope this isn't a decision influenced by cost. Post-exposure treatment costs about $1500 per person, and they expect that this protocol will result in "hundreds" of fewer people receiving treatment. The treatment of all people sleeping in houses with bats actually costs a huge amount of money to prevent a small number of cases. However, what is the cost (financial and otherwise) of even a single case of rabies that could have been prevented? That's a lot harder to incorporate into a risk analysis. Personally, if I had a bat in the house overnight and my kids were potentially exposed (again!), I'd go for post-exposure treatment without any hesitation. Call me a paranoid parent if you will, but I'd sleep much better at night (for years, since the incubation period following exposure can be a long, long time).
The Cherokee Scout reported a story about a North Carolina man that was attacked by a rabid fox in his own home. It seems he was awakened one morning by scratching at the front door. Thinking it was his cat, he opened the door, only to be greeted by a rabid fox that bit "plumb through [his] big toe", rampaged around the house, then bit his other foot. He killed the fox using a mop handle (definitely self defence), and it tested positive for rabies (no surprise here!). This was the sixth confirmed case of rabies in the county since March 16, 2009, indicating that people in that area should be particularly cautious. Marshall Duggan, the man that was attacked, was treated for his bite wounds and is now undergoing rabies post-exposure treatment. The morals of the story are:
- Be wary of rabies, particularly when an outbreak is underway. Make sure, as in this case, that animals are tested if there has been potential exposure (e.g. a bite).
- Make sure your pets are vaccinated against rabies.
- Keep your cats indoors. Mr. Duggan is lucky his cat wasn't exposed to rabies or killed by the rabid fox.
- Don't trust foxes that knock on doors.
More information about rabies can be found on the Worms & Germs Resources page.
ProMed mail reports two more rabies fatalities in an ongoing outbreak in Bali, Indonesia. The first person was bitten by a stray dog, which always must be considered a potential rabies exposure, especially in an area where an outbreak is underway. He received one rabies shot but did not undergo the whole post-exposure series because of a fear of needles, and he died.
The second person was bitten by both a stray and a pet dog, another clear indication for post-exposure treatment. She refused treatment because of a fear of needles, and also died of rabies.
These were two completely preventable deaths. The decision to forgo treatment almost certainly cost these people their lives - rabies is preventable with appropriate and timely post-exposure treatment. These cases also highlight the need for proper education of the public when it comes to rabies, both in terms of avoiding strays and the need for prompt attention when there's potential exposure to the disease. I have no idea how forcefully medical or public health personnel explained the need for proper treatment. For people that want to decline treatment, aggressive and comprehensive education is needed. Ultimately, people are allowed to make bad decisions, but we need to make sure they at least make informed bad decisions.
There are various other concerning issues with this outbreak, particularly the government's response to it. Multiple sources have apparently advised the government that aggressive vaccination and halting of dog movement between the peninsula and the mainland could contain this outbreak. So far, this has not been done. Amazingly, importing rabies vaccine into Bali was illegal until December 2008, and it is still illegal to vaccinate dogs outside of the outbreak area! The cost of vaccination has been used as an excuse not to do so. Certainly, financial issues are important in developing countries. However, the estimated cost is only about $0.50 US per dog. When one considers that this area is highly dependent on the tourist industry, they need to consider this as an investment to maintain their economy. Would you like to spend your vacation in an area with an ongoing rabies outbreak?
Headlines can sometimes be very misleading. The title of this post is from a news article that implies that rabies is a foodborne disease. The first sentence of the article states:
"A new study has detailed how two people in Asia contracted rabies after eating dog or cat meat."
This is a prime example of why it is so important to read more than just the first few sentences of any article, and ideally find the original source of the information. The article refers to a paper in PLoS Medicine. The paper describes two cases of rabies in men from Hanoi, in Vietnam. One had no known history of an animal bite or other rabies exposure, while the other had been bitten a month before becoming sick by a non-rabid dog (the dog was still healthy when the man developed rabies - if the dog had been rabid at the time of the bite it would have died within two weeks). Both patients had butchered and eaten either a dog or cat, including the brain, within 3-8 weeks of becoming sick.
- The first patient had butchered and eaten a dog that had been killed in a traffic accident. He took out the dog's teeth before butchering it, thinking that this would protect him if the dog had rabies (because rabies is so often associated with bites, he likely didn't realize the virus is actually in the saliva and brain tissue). The skull was opened to remove the brain. The man wore work gloves, and didn't report any injuries during butchering. All parts of the dog that were eaten were cooked first. No one else that ate any part of the dog got sick.
- The second patient had butchered and eaten a sick cat that had been acting abnormal for a few days. Again, all parts of the cat that were eaten were cooked first, and no one else that ate any part of the cat got sick. However, the man who developed rabies had prepared the cat's brain for cooking using his bare hands.
In both cases, the affected people were exposed to animals that were sick (cat) or may have been sick (dog hit by car). Only the people who butchered the animals got rabies, while no one else who ate the animals got sick. It is most likely that the two men were exposed to rabies virus during butchering, through contact of infected nervous tissue (e.g. brain) with any tiny bit of broken skin, or even possibly the eyes, nose or mouth, before the tissue was cooked. In Vietnam, butchering (not eating) dogs is a recognized risk factor for developing rabies. It is extremely unlikely that eating cooked meat from a rabid animal would result in transmission of rabies to a person.
"Rabies is a neglected and severely under-reported zoonotic disease in developing countries, killing each year worldwide an estimated 50,000 to 60,000 people, mostly children with terrible suffering and a much higher number of animals... Eliminating rabies in dogs is the optimal control method for preventing spread of the disease."
They also say:
"Dog vaccination and stray dog population control are more efficient and cost effective that post bite treatment in humans."
As with many diseases, prevention is much more effective (and potentially cheaper) than treatment. As OIE Director General Dr. Bernard Vallat explains, "The cost of a post-bite treatment in humans is about twenty to one hundred times more costly than the vaccination of a dog. Currently with only 10% of the financial resources used worldwide to treat people after a dog bite Veterinary Services would be able to eradicate rabies in animals and thus stop almost all human cases."
I think that the sentiment is excellent; we need to focus on vaccination. However, the thought that we could eradicate rabies altogether seems a little optimistic and surprisingly naive. Eradication of a disease such as rabies that has multiple wildlife and stray animals as hosts is difficult, and bordering on impossible. Providing more money for vaccination is excellent, but one of the major problems with rabies control in developing countries is actually vaccinating the animals, even if lots of free vaccine is available. Dedicating personnel and logistical time and money for vaccinating dogs may not be high on the priority list in many countries with other major economic, social and healthcare system challenges. Catching and vaccinating all stray animals is not going to happen. Vaccinating as many animals as possible is important, along with stray animal population control, education of the public about bite avoidance, education of the public and healthcare personnel about bite treatment and prompt availability of adequate post-exposure treatment.
With a good medical and public health system and an informed population, rabies deaths could one day be few and far between. Emphasizing more money for vaccination in the absence of other efforts isn't addressing the big picture. In a perfect world, we'd be able to vaccinate all animals - unfortunately, our world is far from perfect, and while thinking about best-case scenarios is good, we need to focus on what is practical and achievable. That involves more money for vaccination, along with broader approaches by groups such as Vets Without Borders.
A large outbreak of rabies continues to have devastating effects in Angola, Africa. While rabies outbreaks are not uncommon in some parts of the world, the number of people affected in this outbreak is remarkable. A hospital in Luanda, the nation's capital, has diagnosed rabies in at least 93 children in the past 3 months. All have died. The main source of the disease in this case is Angola's large stray dog population. Stray dogs can transmit rabies to other dogs and people through bites. The poor socioeconomic status of the country increases the risk of outbreaks like this because:
- Vaccines are not readily available (for dogs or people)
- It is difficult to organize and fund vaccination programs for stray dogs
- It is difficult to educate the general population about how to avoid and manage rabies exposure
- The healthcare system is relatively limited
These problems, all related to a poor economy, create a "perfect storm" for a rabies outbreak. The shortage of human rabies vaccine and the high cost of post-exposure prophylaxis (PEP) makes it much more likely that people will actually develop signs of rabies after being exposed. The cost of PEP is more than the average Luanda family makes in a month.
Fortunately, the outbreak seems to be waning. However, without improvements in stray dog management (including vaccination) and access to adequate PEP, future outbreaks and problems are inevitable. It was reported that "adequate" supplies of canine rabies vaccine are now available. Hopefully, a concerted effort to vaccinate as many dogs as possible will reduce the rabies load in the canine population, thereby helping to decrease the risk to the people living in the area as well.
A search is on for a woman in Spring Hill, Florida who was attacked by a rabid cat while jogging. The cat apparently jumped on the woman's back without provocation while she was out for a jog. The cat was later caught and found to be rabid, but not until after it had attacked three more people and a dog. Since the cat has been confirmed as rabid, and it is certainly possible that it may have bitten the jogger during the attack, there is a real risk to the unknown woman of developing rabies.
The potential for rabies exposure should be considered following any bite from a mammal. If the animal is acting strangely (attacking joggers would certainly qualify) and it's rabies vaccination status is unknown, the concern is much greater. It's important to identify any animal that has bitten someone so it can be evaluated to deterimine whether there is a risk of rabies. This would include examining the animal for clinical signs of rabies, and checking its vaccination status. Being vaccinated against rabies doesn't guarantee the animal doesn't have rabies, but it makes it very unlikely. Depending on the degree of risk and the status of the animal, observation of the animal in the home, strict quarantine, or euthanasia and testing might be indicated.
This jogger probably needs to be treated for rabies exposure, unless a bite can be completely ruled-out. This post-exposure prophylaxis (PEP) consists of an injection of anti-rabies antibodies, followed by 5 doses of rabies vaccine given over 28 days. It's not fun, but it's nothing like the old PEP method that people often hear about, which involved many more injections given in the abdomen. It's a small price to pay to avoid an almost invariably fatal disease.
Some areas of the world are fortunate enough to be rabies-free. However, there's a closely related virus that is of concern in many of these areas: European bat lyssavirus (EBLV). This virus is present in bats in various countries and can occasionally be transmitted to other animals. A recent report in the journal Emerging Infectious Diseases describes EBLV infection in two cats in France. Both cats died, although the actual cause of death of one of them was uncertain (the animal was also infected with feline immunodeficiency virus (FIV)).
Infection with EBLV in domestic animals is very rare. The risk to dogs and cats is probably very low, but obviously not zero. Avoiding contact with bats is always a good idea. Even in rabies-free areas, measures should be undertaken to keep bats out of houses, and people or animals should never touch sick or injured bats.
The risk to humans from infected domestic animals is unclear. It is thought that dogs and cats pose little risk for further transmission. While susceptible to infection, they are unlikely to transmit EBLV, probably because they produce very low levels of virus. Although there are no clear data about using standard rabies prophylaxis for the prevention of EBLV, it is believed that it would be effective if the virus was transmitted from an infected animal to a person. One cat in this report bit a veterinarian, who received a rabies vaccine booster since he/she had previously been vaccinated against rabies. Fifteen people who were exposed to the second cat underwent the recommended rabies post-exposure series of shots as a precaution.
Even in rabies-free areas, bites from bats or other wild animals should be taken seriously. They should immediately be cleaned thoroughly with lots of soap and water, and medical attention should be sought.
A big problem with EBLV is that it can be very difficult to diagnose. In this Emerging Infectious Disease report, several different tests were used and results were inconsistent. Multiple tests are probably needed to make a diagnosis. It's possible, therefore, that without this kind of comprehensive testing cases could be missed.
Overall, EBLV is a minor concern for public health, but is yet another reason to just use common sense - avoid contact with bats and treat bite wounds carefully, even in rabies-free areas.
Rabies clinics are common in some areas. They are typically one or two day events where people can get their pets vaccinated against rabies at very low cost. The good aspect of these clinics is that some animals that get vaccinated there would not otherwise be vaccinated. The downside of rabies clinics is that they are not the same thing as a normal vaccine appointment with a veterinarian. Rabies clinics are usually "assembly line" vaccination - the goal is to get as many animals vaccinated as quickly and efficiently as possible. The animals are not given a physical examination and there is no discussion with owners about preventive medicine or other problems. Therefore, there is no opportunity to detect and address other health problems, which is (in my opinion) the most important aspect of routine vaccination appointments. There is also no opportunity for vaccination against other important diseases.
Rabies vaccine clinics can be beneficial in situations where some people are unable (or, unfortunately, unwilling) to pay for a normal veterinary examination and complete vaccination. Anything that increases the number of animals vaccinated against this devastating disease is useful. However, rabies clinics also can compromise the health of animals (and potentially their owners) if they are the only routine veterinary contact. They can also end up hurting owners financially in situations where early disease would have been detected and addressed during a regular vaccine appointment. Often, diseases are much more difficult and expensive to treat when they are identified later.
So, while it's obviously tempting to take the cheapest option available, if you can afford a regular veterinary appointment, don't use rabies vaccine clinics. It will be better for your pet and for you to have a regular vaccination appointment with a good physical examination and full consultation.
More information on rabies can be found on the Worms & Germs Resources page.
Until a few years ago, rabies was described as "invariably fatal" in people. A case of rabies in a 15-year-old girl in Wisconsin a few years ago changed that. She managed to survive this deadly disease due to a very aggressive treatment protocol, that was subsequently named the Milwaukee Protocol. This led people to call start calling rabies "almost invariably fatal". Unfortunately, subsequent attempts to treat people with this protocol failed, and there has been some debate about whether the treatment was really effective - rabies virus was never actually isolated from the first survivor, and some have speculated that the girl was in fact infected with "defective" virus that was less virulent. The patient also developed a very high antibody level against rabies virus, and this abnormally profound immune response to the infection may have also played a role in her survival. Regardless, the failure of anyone to report similar success using the Wisconsin Protocol dampened optimism about this treatment.
That was until a recent case from Brazil, where another successful treatment was reported in a 12-year-old boy who was apparently infected with rabies. He was recently released from the critical care unit, but still has some neurological problems as a result of his ordeal.
It’s heartening that there has been another survivor of this dreadful disease, but I think we still need to consider rabies "almost invariably fatal". We can't afford to relax one bit about the severity of this disease. It is likely that only a very small percentage of people treated with this protocol will survive, and even fewer (if any) will recover fully. Survival likely depends on very aggressive treatment started very early in disease, as well as a host of other factors such as a strong immune response by the patient and, probably, a lot of luck. Prevention of this disease remains, by far, the best protection for both people and animals.
A few years ago, a tour agent in a Caribbean country tried to convince me that taking my young children in an open-sided vehicle on a drive over the country's highways was perfectly safe. My response was that the laws of physics don't go on vacation when I do - meaning that a car accident with unrestrained children is a bad thing even on a nice sunny island. The same concept goes for infectious diseases: when on vacation, you should try to leave your worries behind, but not your common sense. Travel-acquired diseases are extremely common. Transient, annoying, but usually self-limiting problems like food poisoning affect thousands of people on vacation, but more serious diseases can also be encountered.
A recent rabies outbreak in dogs in Bali highlights some of these concerns. Rabies is common in stray/feral dogs in many countries, and there can be huge dog populations in some common tourist areas. It's human nature for many people to want to feed or pet these strays. However, people often forget about the potential for rabies exposure. An additional concern is that proper post-exposure treatment for rabies may not be readily accessible in many countries. Some countries are mounting aggressive vaccination programs of strays in response to the risk to local inhabitants and tourists, but people need to be aware that the risk exists and can be very significant. It has been reported that 23 people from Britain have died of rabies acquired abroad since 1946. That's not a huge number, but it's not good if you are one of those 23, and such tragedies are preventable.
Remember these simple points when you are on vacation:
- Stay away from strays (dogs or cats).
- Report dogs that are acting strangely to local authorities or someone else that might be able to help (such as a hotel concierge).
- If you are bitten, take it seriously. If you cannot identify the dog, confirm its rabies vaccination status and ensure that it is properly quarantined, you should probably be considered exposed to rabies. If that is the case, get post-exposure treatment as soon as possible.
- If you are going to have contact with stray dogs or wild mammals during your vacation, such as volunteering with animal care groups, get vaccinated against rabies before you go.
- Always remember to pack some common sense.
I admit I was a little slow picking up this Christmas story, but it's still "entertaining" (for lack of a better word). I've never thought about it, but I guess there are certain risks associated with playing Santa for pet photos. I'm not one to take my pets for pictures with Santa, but many worthy groups raise funds this way. During one recent event, "Santa" was bitten by a less-than-cooperative feline named Benny, who apparently didn't appreciate being in the company of the dogs which had also come. To make things worse, Benny wasn't your average cat - he was a pixie-bob, a very large breed of cat that resembles the North American bobcat (but it is in fact an entirely domestic breed)(pictured at right, from NBC10). After the incident, Benny's owners apparently produced proof of rabies vaccination, and everyone seemed fine. Besides the rabies concern, cat bites are not necessarily innocuous and severe complications can occur. That's one aspect of the story which hopefully didn't develop.
My point in writing this is to reiterate (again) my frequent statement that people need to make sure that their pets are properly vaccinated, even those that stay indoors all the time. Indoor cats can still bite people that visit, they can be exposed to rabid bats, and they can (not infrequently) escape. In this incident, if the cat had not had proof of rabies vaccination, a long quarantine period or even euthanasia may have been required - certainly not what anyone expects from a Santa photo-op.
And... maybe it's not a good idea to take large cats into strange places surrounded by dogs and thrust them into the arms of a strange person...something to consider.
In 2008, the American Association of Equine Practitioners (AAEP) published updated vaccination guidelines for horses. One of the changes from the previous set of guidelines was the inclusion of rabies as a core vaccine (meaning every horse should receive it). There was lots of discussion about this at the recent AAEP Annual Convention in San Diego, CA.
Some veterinarians don't like the idea of vaccinating every horse against rabies. Just like veterinarians and owners of dogs and cats who are concerned about over-vaccination in these species, the same concerns exist in equine medicine. Equine rabies vaccines are not approved for use every three years like some canine and feline vaccines, so they still need to be given every year until someone can determine for how long a vaccinated horse is protected from infection. Furthermore, there has never been (to my knowledge) a case of human rabies due to transmission from a horse. These are all valid points, but there are also a lot of reasons why including rabies as a core vaccine for horses is very good idea:
- Rabies is a very deadly disease, in both animals and people. To some owners, their horse is every bit a part of their family as any dog or cat could be. To other owners, their horses represent a great investment, and part of their livelihood. Even if the risk of disease in horses is low, protecting them is safe and easy, so it just makes sense. As the saying goes, an ounce of prevention is worth a pound of cure, but when there is no cure and prevention is so simple... you do the math.
- Rabies vaccination is extremely effective in horses, producing an excellent immune response even with a single dose. It does not require complex adjuvants that some other vaccines need to stimulate the immune system, which also makes it less likely to cause an abnormal vaccine reaction.
- Rabies is not a seasonal disease like many of the respiratory viruses or insect-borne diseases (e.g. West Nile) for which horses are also typically vaccinated. Rabies boosters only need to be given once a year, so this can be done during a time of year when no other vaccines are required, if there are concerns about giving too many vaccines at once.
- Horses live outside and in barns. Most are far less supervised than dogs and cats, but even these animals are at risk of rabies exposure. A rabid animal could easily be "brave" enough to attack a horse, even though it normally wouldn't. Bats can also easily get into and out of many barns - you may never know one was there, and finding a bite mark from a bat on a horse would be like looking for a needle in a haystack, but that's all it takes to transmit the virus. So it makes sense to give your horse added protection by vaccinating it.
- Rabies in horses may not look like rabies at first. One of the most common early signs is actually colic. A rabid horse that looks like a colic may expose the people who are trying to look after it before they realize what the horse has. In other horses the signs may be recognized too late, like the rabid horse that was found at the Missouri State Fair earlier this year, that resulted in exposure of many people.
- While rabies transmission from horses to people has not been documented, rabid horses have killed people, particularly horses that develop the "furious" form of rabies, which can cause them to become very violent.
For more information on rabies, see our rabies archive or the information sheets available on the Worms & Germs Resources page. For more information on rabies in horses specifically, visit our sister site, www.equIDblog.com.
Rabies is very unique virus in many ways. One unusual aspect of rabies is the amount of time that can elapse between exposure and development of clinical disease (illness). This is called the incubation period of virus. Usually people develop rabies within six months of exposure (e.g. from a bite from an infected animal like a dog or a bat). However, longer incubation periods can occur.
Some rabies cases with purportedly long incubation periods can't be confirmed because the person may have been exposed to the virus multiple times. In countries where rabies virus is not present, it is much easier to tell when a person is exposed because they had to have been traveling abroad. Such a case was reported in the December 2008 edition of the journal Emerging Infectious Diseases. The case described was that of a ten-year-old girl that died of rabies in Australia, a country which is rabies-free. The child had lived in Australia for five years, but previously lived in Vietnam and Hong Kong, where rabies is common. Since she had not left Australia in the last five years, it is almost certain that she was exposed to the virus at least five years before developing disease.
One potential complicating factor in some rabies-free countries is the presence of one or several bat lyssaviruses, which are very closely related to the rabies virus (in fact, the rabies virus itself belongs to the Lyssavirus genus). These viruses can also cause disease that looks very similar to rabies. Human cases of infection by bat lyssavirus were reported in Australia after the child in the report died of rabies, but analysis of viral RNA collected from the girl recently confirmed that it was rabies, and not another lyssavirus. Also, typing of the rabies virus showed that it was most consistent with a Chinese strain, which suggests that she acquired the infection in Hong Kong. This demonstrates that rabies can have a very long incubation period.
Rabies is a devastating disease but one that is largely preventable in people, given proper attention and access to post-expsoure treatment. More information about rabies can be found in on the Worms & Germs Resources page and in our rabies archives.
Photo: Electron micrograph of a rabies virus (source: Tektoff-RM/CNRI/Science Source/Photo Researchers, Inc.).
A 55-year-old man in Missouri recently died of rabies. He was the first human rabies victim in that state in close to 50 years. He was apparently bitten by a bat in mid-October and started to show signs of rabies about six months later.
This tragic incident highlights a few important points. All bats should be considered rabid until proven otherwise. Any bite from a bat should be considered rabies exposure. If this person had received treatment for rabies exposure, he almost certainly would not have developed rabies. Post-exposure treatment consists of a dose of antibodies against the rabies virus as well as a series of 5 vaccinations over four weeks. These are normal vaccines given in the arm - not like the old horror stories of reaction-prone vaccines given in the abdomen.
- Treat every bat as rabid. If you are bitten or may have been bitten (i.e. you were asleep in a room with a bat), you should consider yourself exposed unless the bat is tested and shown to be negative.
- If you are exposed to rabies, get proper treatment. It's not a big deal and it can save your life. See this post for my experience with bat rabies.
- Dogs and cats must be vaccinated against rabies. Even if they don't go outside they can still be exposed. It's also the law in most areas.
- Bat-proof your house. Seal up holes and crevices where bats may hide or through which they may get into your home.
- If you wake up in a room and see a bat, don't let it out. It must be caught and tested for rabies, or you should receive post-exposure treatment. Bats can bite sleeping people without them noticing.
- Wildlife should want to stay away from people. Wild animals that are acting strangely or do not appear afraid of people could be rabid. Stay away from such animals and report them to your local animal-control official.
A recent report in the Journal of the American Veterinary Medical Association by Jesse Blanton and colleagues provided a detailed report of rabies infection in the US in 2007. Here are some of the more interesting points:
- Rabies was diagnosed in 7 258 animals and 1 person. That's a 4.6% increase in animals from 2006, but 2 fewer human cases.
- 93% of cases were wildlife: 37% raccoons, 27% bats, 20% skunks, 7% foxes.
- 0.8% of cases were in cattle and 0.6% were in horses.
- 4% of cases were cats, with the largest numbers of feline cases in Virginia, Florida, Pennsylvania, North Carolina, Maryland, New Jersey, New York, Georgia, Texas and Kansas. Cat cases peaked in June and July.
- 1.3% of cases were dogs, with the largest number of canine cases in Texas, Georgia and North Dakota. Dog cases did not appear to have a seasonal pattern.
- Small numbers of a variety of other species were diagnosed, including pigs, wolves, opossums, bobcats, coyotes, otters, bears, deer, mongooses (in Puerto Rico), groundhogs and beavers.
- The largest number of rabies cases occurred in Texas (969).
- The infections that occurred were due to several rabies virus variants in circulation in North America, including raccoon rabies virus, skunk rabies virus, arctic fox rabies virus, bat rabies virus and Texas gray fox rabies virus. In each region of the continent, one or more of these rabies virus variants may be more common.
- No infections with canine rabies virus were identified. Dogs and coyotes were infected by other variants of the rabies virus, but not with the dog variant. It is believed that dog-to-dog transmission of canine rabies virus no longer occurs in the US.
- The one human rabies case in 2007 occurred in Minnesota, and was probably due to exposure to a rabid bat.
In some areas, pet vaccines are readily available from multiple sources, including the internet. Some people like to purchase vaccines and administer them to their pets themselves in order to save money. But are the cost savings really worth the risk? Here are some things to consider:
- Your veterinarian gets vaccines through a reputable distribution system, which ensures quality control, tracking of products and proper shipping and storage conditions. When buying elsewhere (especially the internet), you don't have the same level of assurance. Vaccines that have been improperly handled or stored may not be effective.
- Vaccines and drugs from some sources are of questionable quality, and you can't always be sure that you're actually getting what you wanted. Ineffective vaccines or contaminated products are a big concern. It's not saving you money if the vaccine doesn't work!
- While uncommon, vaccine reactions do occur. If your pet has an anaphylactic (severe allergic) reaction at a veterinary clinic, the chances that your pet will survive are much greater because the needed expertise, drugs and equipment are readily available. You don't have these things at your house.
- If your pet develops a problem associated with a vaccine administered by your veterinarian, the vaccine manufacturer may get involved and assist with the problem. This will NOT happen if you buy the vaccine from another source and give it yourself.
- Rabies vaccines MUST be given by a veterinarian. (In some areas it's illegal for a non-veterinarian to even possess rabies vaccine.) A pet that has received a rabies vaccine by a non-veterinarian is considered unvaccinated by public health authorities. If an unvaccinated animal is exposed to rabies, the repercussions may be much more severe, and may even include euthanasia.
- Vaccination is just one part of your pet's "wellness program." Some of the pressure for people to vaccinate their own pets is a failure of the veterinary profession to adequately emphasize the importance of preventive medicine, of which vaccines are just one component. Simply charging an owner for "annual vaccines" leads people to want to vaccinate their pets themselves because they can get the vaccines for much less money. Veterinarians need to emphasize that what they are charging for (and what is the most important component of the preventative medicine program) is an annual physical examination and health consultation, and that only a small portion of the fee is for the vaccines.
Vaccination is a minor component of your pet's preventive medicine program. A careful physical examination and consultation about potential, developing and ongoing health issues are the most important parts of this program. Even if you vaccinate your pet yourself (which is still not recommended for the reasons above), it is still critical that your pet has an annual examination. It's better for your pet's health, and it can be easier and cheaper in the long run because problems can be detected and treated early.
I'm constantly amazed at what some people do with bats. Bats are a leading cause of human rabies exposure in North America. Despite extensive efforts to educate people about the importance of avoiding contact with bats, some people still either don't know or don't take these warnings seriously.
The latest bizarre example of stupid things done with bats occurred in Montana, where a parent brought a dead bat to a school and let young children (kindergarten and grade 5 students) touch it. Touching a bat in itself is a bad idea, let alone touching one that has died of unknown causes and encouraging kids to touch it. The teachers apparently had no objections to this activity. The parent who brought the bat had the students use an alcohol hand sanitizer after touching the creature, but it is still very irresponsible for someone to encourage children to touch a high-risk animal, regardless of what is done after. I'm sure the parents of the children didn't know beforehand, and certainly some were no doubt very upset when they found out about the incident (or livid would be a better description, if it was my kids that were involved). School officials did not find out about the dead bat until after its little visit, at which time the local and state public health authorities were contacted. The bat was tested and was positive for rabies.
Overall, the risk of rabies transmission is probably low in this case, but not zero. It has therefore been recommended that the 80 students that may have touched the bat be given post-exposure rabies shots, which may cost up to $800 per child!. Another ten children may have touched the bat at a soccer practice - for a dead bat, it sure covered a lot of ground!
- Never touch a bat, dead or alive. Obviously, if you shouldn't touch a bat, you shouldn't encourage kids to do so either!
- Unstructured and unapproved contact with animals in classrooms should be prevented. Animals can be good educational tools, but only if student and animal health and welfare are properly addressed.
More information on Rabies is available on the Worms & Germs Resources page.
This Sunday, September 28th, is World Rabies Day. The goal of this day its to raise awareness about rabies, a disease that still kills thousands of people and animals in many parts of the world every year. While human rabies is thankfully rare in most developed countries, it is a major health concern in many other regions. Even in countries such as Canada and the US, where human cases are uncommon, diligent vigilance is required, because rabies continues to be present in wildlife, and therefore people and pets can still be exposed to this deadly disease.
A key part of rabies prevention, which is also a major focus of rabies education programs, is the need for vaccination of pets, even strictly indoor pets. Rabies vaccination is a cheap and effective way of protecting your pet, yourself and your family from this disease. It's also required by law in many areas. The implications of rabies exposure of pets that are not properly vaccinated can be severe, possibly including euthanasia or very long quarantine, even if they are not infected.
Many groups are holding events to increase awareness about rabies, such as the People and Pets Walk to End Rabies which is being held by the University of Guelph. Information from an advertisement for this event states "Although rabies does not seem like an issue at home, it is a major health problem for both humans and animals in developing countries, claiming the life of one person every ten minutes. If we work together, we can make a difference. Please show your support and join us at the walk to help make rabies history!" That statement should make it clear why we talk about rabies so much. One human death every 10 minutes is a startling figure for a disease which we should be able to control.
More information about rabies is available on the Worms & Germs Resources page.
If you are looking for an interesting website to play around with, you should try HealthMap. This is a website created by the Harvard-MIT Division of Health Sciences and Technology that maps infectious disease reports from various sources. You can search by region and see what disease problems have been reported recently, or select specific diseases and find out where they've been reported. Some examples are shown below. The top image shows all disease reports worldwide (in the last 30 days), while the bottom image shows reports of Salmonella in North America during the same time period. The site relies on reports of diseases (many cases of various diseases occur but are never reported), so it focuses mainly on outbreaks or high profile cases , but it is still quite interesting.
Above: All reported disease outbreaks/cases worldwide in the last 30 days.
Below: Reported outbreaks/cases of Salmonella in North America in the last 30 days.
See the HealthMap site for more details.
Rabies is an important disease that is almost always fatal. An important part of rabies control programs is mandatory vaccination of pets such as dogs, cats and ferrets. In general, rabies vaccination is very safe and effective. Complications from rabies vaccination are rare, but in recent years concerns have been raised about vaccine-associated sarcoma, a type of tumour that can develop at the site of vaccination. Since this complication was recognized, the vaccines themselves and the way they are administered have been changed in order to decreased the likelihood of this problem occuring, but the risk cannot be eliminated completely. For this reason, some people have tried to avoid having their pets vaccinated for rabies.
A blood test can be performed to determine antibody levels (also called a titre) against rabies virus. However, there is not enough information available to determine what antibody titre is high enough to say that an animal does not need to be re-vaccinated. Skipping rabies vaccination based on blood test results is dangerous and not recommended. While rabies is uncommon in most areas, exposure can occur, even in strictly indoor animals (e.g. if a bat gets into the house). Rabies vaccination is a legal requirement in most areas of Ontario. The implications of rabies exposure in an animal that is not "up-to-date" on its vaccines can be severe, including prolonged quarantine or euthanasia. I do not know of any jurisdictions that allow rabies antibody levels to be used in place of vaccination, and animals that are not recently vaccinated are treated as non-vaccinated, regardless of their antibody titre. The risk to your family or your pet from rabies is greater than the very tiny risk of vaccine-associated sarcoma. If you care about your pet and your family, make sure your pet is properly vaccinated against rabies.
More information about rabies can be found on the Worms & Germs Resources page.
"Unintended consequences" are outcomes (usually negative) of a particular action that are unexpected. For example, in some areas, hospitals now receive decreased reimbursement for MRSA infections. This policy was meant to help encourage hospitals to reduce MRSA infection rates. However, there are concerns are that this has actually lead to decreased MRSA testing (and potentially compromised patient care), because if the MRSA infection isn't documented, payment will not be withheld.
Unintended consequences can be found in many diverse areas. An interesting example was recently published in Ecological Economics and reported by the Toronto Star. It described the unintended consequences that linked use of a cattle drug to rabies deaths in India. Here's here story:
- Didofenac is a drug that was routinely used in cattle in India
- The drug is apparently highly toxic to vultures
- Vultures fed on cattle that died of natural causes, but that had didofenac in their bodies
- Millions of vultures died, which led to a larger food supply for feral dogs
- It was estimated that this lead to 5.5 million more feral dogs in India from 1992 to 2006
- These additional dogs would have accounted for at least 38.5 million dog bites
- Rabies is a serious problem in feral dogs in India
- In India, 123 people die of rabies per 100 000 dog bites.
Putting these numbers together, the unintended consequences of didofenac use in cattle may have result in 47 000 human deaths from rabies and $34 billion in health care costs. There are a lot of assumptions in this report, but it is an interesting story and highlights the unpredictable nature of infectious diseases, and the varying effects that seemingly unrelated actions can have.
More information on rabies can be found on the Worms & Germs Resources page.
There is no doubt that the beneficial effects of vaccination greatly outweigh the risks, but even so adverse effects cannot be ignored. Information about duration of immunity after vaccination, vaccine safety and disease rates need to be considered when determining how often to vaccinate an animal. Unfortunately, minimal information is available about how long most vaccines are protective in dogs and cats. So there is a logical tendency to err on the side of caution and vaccinate more frequently, rather than less.
New guidelines for vaccination of cats are now available from the American Association of Feline Practitioners. The guidelines recommend longer intervals between vaccines in most older cats that have been previously (and adequately) vaccinated.
Rabies vaccination also has important legal aspects to consider. Different jurisdictions have different requirements. While a three-year rabies vaccine is available, many regions still require more frequent vaccination. Even if an animal is properly vaccinated with a three-year vaccine, if local rules require yearly vaccination, an animal vaccinated more than one year earlier could be considered unvaccinated. This can have a tremendous impact if the animal is exposed to rabies - it could mean the difference between monitoring the pet at home, or a long quarantine, or even euthanasia. Therefore, it is important to consider the duration of immunity induced by the rabies vaccine used AND the local regulations. Rabies vaccination is even important for indoor cats.
The bottom line is:
- Vaccination is an important part of your pet's preventive medicine program.
- Different cats need different vaccination programs, depending on their age and what diseases they may be exposed to.
- Potential vaccine reactions should be reported to your veterinarian, who should then report them to the appropriate regulatory authorities, so that a better understanding of adverse reaction rates can be obtained.
- Don't let vague fears of adverse reactions deter you from vaccinating your pet. If you have concerns, get informed, talk to your veterinarian, and get accurate information.
Some animals make good pets, some are mediocre and some are completely inappropriate. Bats are in the last category. Bats are the main vector for rabies virus in North America and they do not have to look sick to be carrying rabies. Bats can bite when being handled and bites are often very small, so they are not always taken care of or even noticed. A person not reporting a seemingly harmless bat bite is a common history in human rabies cases.
Even if rabies didn't exist, keeping pet bats would still be a bad idea. Bats are very difficult to care for properly, and rarely survive for long in captivity, except in well-run zoos with excellent facilities and very knowledgeable caretakers.
More information on rabies is available on our Resources page.
This incident highlights a few things, including the fact that rabies, even in dogs, can be quite common in some areas of the world, and that movement of animals across borders may increase the risk of introducing infectious diseases. Certainly, cases such as this should not be used to say that these dogs should not be adopted. Rabies (or other serious disease) is a rare event in these situations, and the overall risks to people are minimal if proper procedures are followed. This includes making sure that all animals remain accounted for after arrival, and pursing proper diagnostic testing in the event that they show signs of illness (as was done here). The other dogs that came back with the rabid dog are being monitored. The risk of transmission from this dog to the others is quite low, since it is unlikely that the dog was able to transmit rabies 3 weeks ago, well in advance of developing signs of disease. In some cases it can be weeks to months from the time a dog (or other animal) is exposed to rabies until they become infectious to others. Presumably, people that had contact with this dog recently are now undergoing post-exposure treatment.
More information about rabies can be found on the Worms & Germs Resources page.
You should see a doctor about any cat bite on a hand, over a joint, over a tendon sheath (such as the wrist or ankle), over a prosthesis or implant, in the genital area, or that causes a deep tear. You should also see a doctor for any bite if you happen to have a weakened immune system for any reason (e.g. HIV/AIDS, cancer or transplant patients).
The best way to prevent infection is to prevent the cat from biting you in the first place!
- Use common sense – know how to handle a cat properly so that it is not frightened or uncomfortable. If a cat growls at you or tries to get away, let it go!
- Don’t let cats play with your hands, feet or hair. Use a nice cat toy instead.
- Don’t approach strange cats, especially strays. If you are bitten by a cat that may not have been vaccinated for rabies, it is very important to report the incident to you local public health department and your doctor, as you may need to receive rabies post-exposure prophylaxis (PEP).
Important points to remember about rabies and bats are:
- Never touch a bat.
- Consider every bat to have rabies until proven otherwise.
- If you have slept in a house overnight with a bat, you are considered exposed. Unless the bat is caught and tested (and shown to be negative) you should undergo post-exposure treatment.
- If you or your pet may have been in contact with a bat, try to catch it (safely) so that it can be tested for rabies.
- Vaccinate your pets against rabies, even if they never leave the house.
Photo: Little brown bat (M.B. Fenton)
If you care about your family and your pets, vaccinate you pets against rabies.
More information about rabies is available in our Resources page.
Various bacteria that can cause diarrhea in people can be carried by kittens, including Salmonella and Campylobacter. These are shed in the stool of infected animals, and people can become ill from handling the animal or stool-contaminated areas. Kittens may have higher rates of carriage of these bacteria than adult cats. Another bacterium that can be carried commonly by kittens is Bartonella henselae, the cause of cat scratch disease. This is transmitted by bites, scratches and fleas, and is just one reason for proper flea control.
Stray kittens are also more likely to carry Toxoplasma, a parasite that is a concern in pregnant women and immunocompromised individuals. Other intestinal parasites such a roundworms are also a concern. Kittens are more likely to have these parasites than adult cats. Stool contamination of the haircoat is presumably more common in kittens as well because they are not as good about cleaning themselves as adult cats. So just handling a kitten, even if you avoid its stool, may result in exposure to some of these parasites and bacteria.
Rabies is always a concern, and widespread exposure of people to rabies has occurred from infected litters of kittens. While uncommon, rabies is a major concern because it is almost invariably fatal. Any stray (or recently rescued) animal that starts acting strangely should be considered a rabies-suspect and be taken to a vet immediately. [More information on rabies, and other topics, is available in our Resources page].
Stray kittens can also carry various infectious diseases that can be transmitted to other cats in the household, such as feline leukemia virus, panleukopenia, rhinotracheitis and calicivirus.
Overall, the risks from adopting stray kittens are low, but they are real. If you are going to adopt/rescue a stray kitten, keep these things in mind:
- Take the kitten to your vet as soon as possible to identify any health issues and determine the required vaccination, deworming and flea control program
- Wash your hands after handling the new kitten
- Keep the new kitten in a confined area while litterbox training is underway to reduce accidents throughout the house
- If you have another cat, make sure it is up-to-date on vaccinations before the kitten comes into the house.
- If the kitten gets sick, make sure it is taken to a vet. If it dies suddenly, make sure you take it to your vet to determine whether testing for rabies is required.
- Pregnant women and households with immunocompromised individuals should not adopt stray kittens.
Wildlife should be left in the wild. While some wild animals, especially babies, are hard to resist, little good usually comes from intervention of the general public. This is particularly true when well meaning people ‘rescue’ baby wildlife. Often, ‘orphaned’ wildlife are not orphans; the parents are hiding nearby and would have returned. Few animal facilities are properly equipped or licensed to properly deal with wildlife, and these ‘rescued’ orphans often end up being euthanized. Some people try to nurse these animals themselves but few can do it properly. It’s also illegal in many areas. Add that to the obvious risk of rabies, as highlighted here, and it should be clear that wildlife should be left alone. It’s also a good reminder of the need to vaccinate your pets because rabies exposure can occur in many different ways. The pets in this situation are reportedly under 45 day quarantine, which is certainly not something you want to do, but is much better than what would happen in many jurisdictions in the case of rabies exposure of an unvaccinated pet (long strict quarantine or euthanasia).
Baby raccoons are very cute and hard to resist, but like many other forms of temptation, danger, in this case in the form of infectious diseases, can lurk just around the corner. More information on rabies is available in our Resources section.
But there are also dangers lurking in the forests – microscopic dangers carried by tiny insects and other bugs. Ticks in particular are problematic. Certain ticks can carry a number of diseases that can make dogs sick, including Lyme disease (caused by Borrelia burgdorferi) and Rocky Mountain Spotted Fever (RMSF)(caused by Rickettsia rickettsii ). Both Lyme disease and RMSF are more common in certain areas where the tick species that carry them are present. You can NOT catch these diseases from your dog, but both you and your dog can be infected by the ticks that carry them. People can also be exposed to these pathogens by accidentally crushing an infected tick while trying to remove it from their dog. Ticks must be removed very carefully to ensure that the entire tick is removed, including the head and mouth pieces, without crushing it. If you're not sure how, contact your veterinarian. Also, the sooner the tick is removed, the less likely it is to transmit certain diseases, so be sure to check your dog thoroughly for ticks when you come back from a walk in the bush.
The Minnesota Department of Health recently reported that the number of cases of (human) Lyme disease increased in that state in 2007. This could be because of spreading tick populations, more people participating in activities in tick-inhabited areas, or increasing awareness and diagnosis of the disease by physicians.
If you and your canine companion will be spending time in some of the wilder and woodier parts of the great outdoors, talk to your veterinarian about what you can do to protect your dog. There are vaccines available for Lyme disease and the bacterial infection leptospirosis (which is also transmissible to people). Flea and tick preventatives are also very important, and many of today’s products are very effective. People should always wear insect repellent when camping or hiking in the woods. Visit the Health Canada website for safety tips on using personal insect repellents. All dogs should be vaccinated for rabies, whether they go camping in the backwoods or they’re house-bound city-slickers.
- Never handle a bat
- Assume all bats are rabid until proven otherwise
- Any contact with a bat is considered to be rabies exposure unless the bat has been tested and shown to be negative. All bat exposures should be reported to the appropriate public health authorities.
- Despite all the old stories, rabies exposure treatment is not horrible…it’s just a series of shots in the arm.
- Vaccinate your pets. You never know when they’ll encounter a bat…inside or out.
More information on rabies is available in our Resources area.
Unfortunately, rabies is common in China, with the number of cases increasing dramatically over the last decade. In 1996, there were 163 humans deaths due to rabies. This number increased to 3380 in 2007. Because of the seriousness of disease, the number of deaths and the low vaccination rate in dogs, a mandatory vaccination policy for dogs has been put in place. Free rabies vaccination is provided annually for each licensed dog. This could have a tremendous impact on the number of rabies cases, at least in certain regions. Control of rabies in rural areas is more problematic because of the lack of an organized registration and vaccination system for dogs in those areas. Perhaps not surprisingly, most cases of rabies occur in these rural regions.
So, the 2008 Beijing Olympics may have benefits for the dogs of China as well, or at least those in Beijing. This is certainly a preferred approach to the reports from last year of mass killing of thousands of dogs (including pets). Let's hope this progressive approach continues and the impact of this horrible disease decreases.
On a related note, the latest human death from rabies in Beijing was a person who was bitten by a stray dog two months before he became ill. He didn't seek medical attention at the time of the bite, he just cleaned the wound himself. If he had been treated for possible rabies exposure, he'd be alive today. While rabies is uncommon in many areas, no bite from an animal should be taken lightly. Rabies should always be considered and appropriate measures taken. More information about rabies is available in our Resources section.
Why should I vaccinate Fluffy, he's an indoor cat? (aka Why I'm glad I vaccinated Finnegan, my indoor cat)
Protocols for rabies exposure in non-vaccinated animals vary between jurisdictions, but long quarantines are the norm, and euthanasia often is chosen.
The take home message is, even with indoor-only animals….if you care about yourself, your family and your pets, vaccinate your pets against rabies. In most places it’s the law. It’s also good sense.
INFORMATION SHEETS specifically for KIDS, for VETERINARIANS, for PHYSICIANS and for PUBLIC HEALTH PERSONNEL are also available on the Worms & Germs RESOURCES page!
Click on the highlighted topics below for information sheets. Topics that are not highlighted are in development and coming soon. Sheets for other animal species and diseases are also under development and will be added when they are available.
- Your veterinarian and physician are your ultimate resource for information about the health of your pets or your family.
- Information provided here is accurate to the best of our knowledge, but infectious diseases can be unpredictable and these sheets are for general information purposes only.
- There can be great variation in disease risks in different geographic areas. The information provided was developed for Ontario, Canada, but most of the information is relevant for other regions as well.
Click on any of the highlighted links below for more information about these horse-related infectious disease topics. Topics that are not highlighted are in development and coming soon. New information will be added as it becomes available, so be sure to check this page regularly for the latest updates.
|Clostridial Myonecrosis||Eastern Equine Encephalitis||Equine Protozoal Myeloencephalitis (EPM)||Neonatal Diarrhea|
|Strangles (Streptococcus equi)||Equine Herpesvirus||Cyathostomes
|Methicillin-resistant Staph aureus (MRSA)||Equine Influenza||Large Strongyles||Colostrum|
|Lawsonia||West Nile Virus||Tapeworms|
All information sheets found on this page can be freely downloaded, printed and distributed. The authors only request that this website (www.wormsandgermsblog.com, previously www.equIDblog.com) is acknowledged as the source. The downloadable files on this page can be opened with Adobe® Reader®. To get the latest version of Adobe® Reader® for free, click here.
2012 International Clostridium difficile Symposium
2012 International Conference on Equine Infectious Diseases IX
2011 ASM-ESCMID Conference on Methicillin-resistant staphylococci in animals
- Miconazole susceptibility of MRSA and MRSP
- Livestock associated MRSA in community hospitals in Ontario
- Equine hospital MRSA surveillance
- Biofilm production by S. pseudintermedius
- Methicillin-resistant staphylococcal pyoderma in dogs, and impact of treatment on colonization rates
- Surgical site infections in a small animal hospital
2011 University of Guelph Centre for Public Health and Zoonoses Symposium
- Pet ownership, interactions and animal-associated disease risks in Canadian households
- Metagenomic investigation of the oral microflora in healthy dogs
2011 Canadian Animal Health Laboratorians Conference
2011 Canadian Association of Clinical Microbiology and Infectious Diseases
- 2011 American College of Veterinary Internal Medicine Forum, June
- 2011 ASM-ESCMID conference on methicillin-resistant staphylococci in animals, Sept