As the Asian Longhorned tick (Haemophysalis longicornis) continues to spread in the US, we wait for it to make an appearance in Canada. This “exotic tick” was introduced to the US from Asia possibly a while ago, but was only first detected in 2017 in New Jersey.  It has since clearly established itself as a resident tick species in many states. It’s pretty much inevitable that it will make it to Canada, with southern Ontario or Quebec being the likely entry points.

This tick is a concern for a few reasons. One is that it’s an aggressive feeder. When you combine that with the biological quirk of females being able to reproduce without mating, you can get massive infestations of these voracious feeders on some animals, to the degree that species as large as cattle can die from blood loss.  (This is similar to what the winter tick (Dermacentor albipictus) can do to moose.)

Haemophysalis longicornis can also be the vector of a various infectious diseases of people and animals. Which diseases this tick can transmit in North America is an current area of investigation, since importation of the tick doesn’t necessarily mean all the potential diseases were also imported. We don’t know the extent of that risk yet.

So, what about companion animals?

There are a few issues to consider with dogs and cats when it comes to this tick as well. One is the potential for health effects from massive tick burdens. Hopefully the risk of serious effects from that is lower than in wildlife and livestock since pets are usually monitored more closely, but it’s still a concern. Disease threats are still pretty unclear at the moment but can’t be dismissed.

The other issue is the potential for pets to act as sentinels for this tick. If you look at the USDA’s latest Situation Report on H. longicornis (including the images above), dogs are #3 on the list of most commonly identified hosts, after the environment and white-tailed deer. This is the case despite any formal surveillance directed at this tick in dogs. It’s not particularly surprising since dogs can spend time in tick-rich areas, running through sites where ticks are looking for a host. As a low-to-the-ground haired species, they can pick up ticks quite easily, and a tick on a dog may be more likely to be spotted than a tick on most other species.

Back to Canada…

The fact that this tick entered the US first has given us a head start for planning, and there are various activities underway to optimize the response to this tick when it’s found, including detection, identification, testing, and communication. The key first step, though, is finding the tick, and finding it as early as possible. Here’s where dog (and cat) surveillance can come in. Since dogs can be such great sentinels for ticks, it’s quite possible we’ll find it first on on dogs – if we’re looking, and communicating.

There are a variety of ways this kind of detection might happen, such as:

  • An owner finding a tick on their dog and taking it to their vet, who realizes it’s different than a typical tick and sends it off for further investigation.
  • A submission to a surveillance program such as our PetTickTracker or, for some provinces, eTick.
  • A tick found as part of ongoing pet surveillance such as our Canadian Pet Tick Survey (active surveillance through participating vet clinics) or our Lifetime Lyme Study.

Tick surveillance is a great example of the potential impact of citizen science. A curious veterinarian or pet owner might be the first to find this tick, allowing a quicker intervention than if we relied solely on traditional sources.

Tick image: https://www.cdc.gov/ticks/longhorned-tick/index.html

It wasn’t a snake and Samuel L. Jackson (presumably) wasn’t there to save the day, but Spirit Airlines passengers on a recent flight had to deal with an unwanted stowaway. During a flight from Charlotte to Newark, a bat started flying around the cabin of the Spirit Airlines aircraft. It likely flew into the plane through an open cabin door at some point and hid out for a while, emerging halfway through the flight. The bat was likely as distressed as the people by its presence in that abnormal, confined space, so it flew around for a while, eventually being caught with a cup and a book, and locked away in a bathroom.

That’s a pretty good way to handle it if you can catch the bat without being bitten. Otherwise, leaving the bat alone makes the most sense, as it’s unlikely to land on or bite anyone, but the passengers would probably have been less impressed with that approach.

Upon landing, the bat was taken away by animal control.  It was presumably euthanized since releasing wildlife well away from where they originated is not commonly done, particularly due to disease transmission risks.

When bats are involved, rabies obviously gets discussed as bats are a prime source of rabies exposure in North America. But, what’s the risk?

  • For rabies to be a concern, the bat has to be rabid (prevalence is usually only up to a few percent in any given bat population) and you have to get bitten (largely avoidable). Aerosol exposure (breathing in rabies virus) is a concern is densely populated bat caves, but I can’t see a single bat (if it was infected) in a space that size, with that exceptional ventilation that is present on modern airplanes, posing any plausible risk.

Realistically, your biggest health risk is probably the concussion you might get from your neighbour who’s freaking out and frantically swinging his laptop.

As the US salmonellosis outbreak linked to contaminated pig ear treats continues, the FDA and CDC are now taking the additional step of advising people to avoid all pig ear treats and for retailers to stop selling them. As the investigation continues, links to treats imported from Argentina and Brazil have been made, but the full scope of the problem is still unclear.

Related to this, Lennox Itnl has recalled Natural Link Pig Ears because of contamination concerns, and the pet store chain Pet Supplies Plus has recalled bulk pig ear treats because of the potential for contamination. Bulk bins are a particular problem because they get topped up regularly, lots of hands go in them and cross-contamination can occur easily.

I haven’t seen any reports or recalls from other countries but it’s likely that similar issues exist given the international market for pig ear treats. So, it’s prudent for people outside the US to take a similar approach (and it’s why we recommend caution with any raw animal based pet treats at all times).

Since the recently reported case of rabies in a man from BC, Canada, I’ve done a lot of interviews. One thing that has struck me is the continued misconception about what rabies post-exposure prophylaxis (PEP) is, and the perception that it’s a long, painful ordeal.

It isn’t (at least not anymore)… and I know that from personal experience.

Rabies PEP is a set of injections given to someone who’s been exposed to rabies virus to prevent (prophylactically) the onset of disease. A long time ago, PEP involved enduring a large set of ~21 injections into the abdomen, which was quite unpleasant. Even though this is no longer the case, there’s an ongoing perception that rabies PEP is bad, painful or difficult (however it is still very expensive).

So, what does current-day rabies PEP involve?

There are two approaches to PEP, depending on whether the person has been previously vaccinated (and has an adequate antibody titre) or not.

PEP for an unvaccinated individual

  • The first day (day 0), the person gets a dose of anti-rabies antibodies (also known as rabies immunoglobulin or RIG), and a rabies vaccine (so the body will make more of its own anti-rabies antibodies).
  • The RIG is dosed based on the person’s weight.  If there is a wound (e.g. bite) where the virus likely entered the body, as much of the RIG as possible is injected around the wound (this can be tricky when the wound is on a small part of the body like a finger).  The rest is given in a large muscle.
  • Then the person get a rabies vaccine booster on days 3, 7 and 14.

PEP for a vaccinated individual 

  • We have it easier. We just get two doses of vaccine on days 0 and 3 (in a large muscle, e.g. upper arm).
  • No RIG is given, as it’s assumed a previously vaccinated person already has some anti-rabies antibodies and will respond to the first dose of vaccine very quickly because the immune system has already been primed.
  • This is the same reason an exposed domestic animal should be vaccinated again as soon as possible, even if it’s vaccines are up-to-date.  The goal is to activate the immune system again to help “intercept” any rabies virus in the body before it can cause infection of the central nervous system.  The response is typically much better in a previously vaccinated animal, and there is no RIG that can be given to animals.

Does it hurt?

  • A bit. It’s no different than any vaccine. I’d say my annual flu shot hurts at least as much as my rabies shots did.

Regardless, a rabies vaccine is a lot better to get than rabies. Anything we can do to encourage self-reporting of potential exposure, including making people aware that PEP isn’t a horrible ordeal, is important.  That message hasn’t apparently gotten out well enough.  However, avoiding exposure to the virus in the first place, by not handling wildlife and avoiding bites from domestic and wild animals alike, should always be the first line of defense.  While PEP may not be as painful as it once was, it is still very expensive and there is a limited supply, so it should be saved for those who truly need it.

The multi-state outbreak of salmonellosis linked to pig ear treats continues in the US. In the latest CDC report on the outbreak, 48 new infections have been added to the investigation since July 3, and 3 new Salmonella types are now involved (Salmonella Infantis, London and Newport). This brings them to a total of 93 cases of infection with the outbreak strains… or, I should say, reported infections. As always, reported cases are likely just the tip of the iceberg, since people who get sick have to go to a doctor, submit a fecal sample, Salmonella has be identified and it has to be linked to the outbreak. Most cases presumably are never diagnosed.

Of the 93 infections, 20 required hospitalization. Fortunately, no one has died.

Contact with pig ear treats has been implicated as the source. This isn’t surprising since they’ve been linked to outbreaks in the past. Pig ear treats are just dried pig ears. Pigs can shed Salmonella, leading to contamination of the treats. They can also be contaminated during handling, processing or later, such as through contamination of bulk bins in stores. The latter might be important in this situation, and there was a recall of bulk pig ear products because Salmonella contamination was identified.

Some key points for reducing the risk of Salmonella in people and pets from treats include:

  • Remember that raw animal-based products are prone to contamination with potentially harmful bacteria such as Salmonella, E. coli and Listeria.
  • Check to see if the treats have been processed in a way to kill bacteria, such as cooking. Dehydrating is not the same thing.
  • Avoid buying treats from bulk bins. All it takes is one contaminated treat (or hand) and many other treats can become contaminated.
  • Avoid feeding raw animal-based treats (such as pig ears) when you have a high-risk person in the household. This includes children less than 5 years of age, people over 65 years of age, pregnant women and individuals with compromised immune systems (e.g. due to illness or drug therapy).
  • Avoid feeding raw animal-based treats in households with pets that fit into high-risk groups as well. Also avoid them in dogs that are used for hospital visitation programs, where the dogs will be in contact with a lot of high-risk patients.
  • Wash your hands after handing any pet treat, especially those from raw animal products.

Rabies is a high-profile disease and human rabies is exceptionally rare in Canada. While rabies is relatively widespread in wildlife in North America, it’s is rare in domestic animals in Canada, and spillover into people is fortunately rarer still because people have less direct contact with wildlife reservoirs, and because post-exposure prophylaxis is so effective if it is given in a timely manner.

However, the risk is ever-present, as was demonstrated by the recently reported case of rabies in a 21-year-old man from British Columbia, the first human rabies death in Canada since 2012, and only the second case on record in BC (the first case in this province was in 2003).

The man was infected after contact with a bat on Vancouver Island in May.  The bat reportedly merely “ran into his hand” so he likely did not realize the risk at the time and did not seek medical attention.  But bats have very tiny teeth, and a small puncture wound from a bat bite can be easily overlooked.  If there’s little damage from the bite and people don’t know about the rabies risk, the contact may go unreported, as in this case.  The encounter only came to light after the young man began to show signs of disease.  Rabies is basically 100% preventable of post-exposure prophylaxis is provided, but it’s almost 100% fatal otherwise.

Rabies infections like this are the tragic result of a breakdown in education and communication regarding rabies risk. People need to know when rabies exposure is a concern, to make sure they seek proper medical care. We have a good public health system that’s adept at handling rabies exposure, but it’s all for naught if the exposure isn’t reported. This case highlights the need for ongoing rabies education, despite the rarity of rabies in people in North America.

I’ve been slow to write about this (and other things lately… busy/lazy) but a rabid feral cat found in the vicinity of Disney’s Epcot Center in Orlando, FL  has attracted a lot of attention. The Department of Health in Orange County has issued a 60 day alert for a two mile radius around where the cat was found, an area that hits Epcot.

Why 60 days?

  • Who knows? You have to pick a number. That’s about all the science that went into that, I assume (since raccoon-variant rabies and bat rabies are both still endemic in most parts of Florida).

Anyway, two Disney employees were scratched by the cat when they encountered it in a parking lot of an office building outside the park. It’s not clear why the cat was caught and tested, and whether it had signs of rabies, but it was, and it did.

Scratches aren’t typically considered a risk for rabies exposure but they’re a grey area. Rabies is transmitted by saliva. There are no salivary glands in claws. However, there’s a theoretical potential of rabies virus being there if the cat had just licked its paw, or if saliva was deposited on the person’s skin during a struggle and was driven into the body by the scratch, or if saliva came in contact with the broken skin afterward. So, while scratches are not technically considered a source of exposure by some guidelines, it’s a case-by-case decision, depending on the circumstances. Since rabies is almost invariably fatal but almost completely preventable with post-exposure prophylaxis, treatment of people that are scratched isn’t uncommon.

What does this mean for anyone visiting Disney?

  • Not much. Rabies is endemic in wildlife in Florida. While dogs get more attention, cats are the most commonly affected domestic animal, probably because outdoor cats tangle with wildlife more often and are less likely to be vaccinated.

This doesn’t really change the messaging relating to contact with animals at Disney, or elsewhere.

  • Stay away from unknown animals.
  • If you are bitten or scratched, wash the area thoroughly with running water.
  • Identify the animal, it at all possible, since if it is caught and quarantine or tested, it’s rabies status can be definitively determined.
  • Stay away from unknown animals. (Yes, I realize I already said that, and yes, that includes cute little stray kittens, since they are an important source of rabies exposure.)

Maybe they need to get rid of all of those over-sized mice in Orlando to help reduce the feral cat population.

New antimicrobial resistance challenges continue to emerge. In the veterinary field (especially in small animals), we have the advantage of seeing what’s happening in human medicine first, since that’s often an early warning system for what we’re going to encounter. We’ve seen a variety of resistant bacteria first became a problem in people, and then became a problem in animals, either because of spread of the bacterium from people to pets, or because of the same inciting cause (antibiotic use) leading to development of similar issues.

Lately, we’ve been working on a lot of resistant Gram negative bacteria like E. coli. In particular, we’ve been studying E. coli (and other bacteria from the Enterobacteriaceae family) that produce extended spectrum beta-lactamases (ESBLs). These are enzymes that break down a range of antibiotics in the very commonly-used penicillin and cephalosporin classes. The bacteria also tend to become resistant to other antibiotics at the same time (by acquiring other resistance mechanisms), making them potentially even harder to treat. A common solution for for infections involving ESBL bacteria is to use drugs from the carbapenem class, such as meropenem.

Unfortunately (but not surprisingly), more use leads to more resistance. Carbapenemase-producing Enterobacteriaceae (CPE) are now a big problem in human medicine as they can be very difficult to treat, especially since some have developed resistance to other last resort drugs as well.

We’ve been looking out for these in veterinary medicine. I’ve seen a few cases, all from the US so far. We don’t use meropenem much (although it can be overused), so there’s less selection pressure in our veterinary patients. However, with more antibiotic use of any sort, rare use of meropenem and the potential spread of CPE from humans to their pets, we’ve known it’s coming.

Our concerns are highlighted but a cluster of 15 cases of CPE infection at the University of Pennsylvania’s small animal hospital. Here’s a summary of the cases from the hospital:

Fourteen dogs and one cat were diagnosed with CPE in the past year.  That’s a pretty astounding and concerning number.

  • A cluster of 6 cases was identified in their ICU in July 2018. A second cluster of 3 cases was identified in September and an additional 6 were identified through June 2019 (it’s not clear to me whether the latter group was a cluster or independent cases).
  • Infected animals were isolated as per hospital protocols.
  • Carbapenem resistance in these cases was due to a gene called NDM-5. Finding the same uncommon gene in multiple isolates of the same bacterial species suggests that these are all linked, but it’s hard to say how the different clusters relate (or if they do).
  • 13/15 infected animals were discharged from the hospital and two were euthanized because of unrelated problems. CPE is usually treatable if the diagnosis is made and a appropriate antimicrobial (and adjunct) therapy is started in a timely manner.

From a population standpoint, I’d be happy to hear that these were all linked infections. That’s not something we want to see in a hospital, but 15 linked cases would be better than 15 individual cases, since the latter would suggest there’s a lot of CPE in the community. CPE are no more likely to cause disease than susceptible Enterobacteriaceae, they’re just harder to treat when they do. Diagnosed infections presumably represent the minority of infected dogs and cats, since the bug most often lives harmlessly in the intestinal tract (and gets passed in the feces, thus creating exposure risk for other animals and people).

One concern here is what happened after discharge from the hospital. An animal with a CPE infection probably also has the bacterium living in its intestine. It’s been shown that dogs infected with ESBL-producing Enterobacteriaceae can shed the bacterium for months. We don’t know much at all about CPE shedding in dogs and cats, but it’s likely that some of these animals have been (or still are) shedding CPE.

This won’t be the last we hear about CPE in dogs and cats. Hopefully it remains a rare issue but we’re trying to figure out more about these bugs and how to limit their spread.

Canine influenza is (once again) causing big problems in some parts of the western US. Following reports of influenza outbreaks in animal shelters in Oakland, California, it’s apparent that it has spread within California shelters and to an Oregon shelter. It is also affecting pet dogs in various cities in California.

It’s not surprising that these problems have surfaced again. H3N2 canine flu has been present in the US since it was first introduced from Asia in 2015, and continual re-introductions are probably occurring from importation of dogs from endemic areas. That’s how we got it in Canada, but we were able to contain and eradicate it Ontario (twice).

Here are a few key points for people in affected areas OR who are travelling with dogs to those areas OR moving dogs from those areas.

  • Canine influenza looks like any other type of “kennel cough.” There’s nothing clinically that says a dog’s illness is “flu” vs “not flu.” Dogs with respiratory disease that have been in affected areas should be considered flu suspects.
  • If your dog has a fever, cough, runny nose or eyes, or any other signs of respiratory disease, keep it away from other dogs. Dogs can shed H3N2 for a few weeks, so keeping any flu cases isolated from other dogs for at least 28 days is the goal.
  • If your dog has signs of respiratory disease, definitely don’t take it to a kennel or other place where there are lots of other dogs. That’s how we end up with rapid widespread transmission.  When the flu virus gets into a place like a shelter or kennel, it spreads quickly. Often, most or all dogs get infected. Some might not look sick, but they can still be infectious.
  • If you think your dog might have flu, call your vet. Don’t just show up at the clinic. If your dog needs to be seen by a vet, calling in advance can let them make plans to reduce the risk of exposure of other dogs at the clinic.

Vaccination against H3N2 can be useful but cannot be relied on as the primary means of infection control. It’s like any influenza vaccination (including the ones used in people) – it’s not going to totally prevent most individuals from getting infected. It’s designed to reduce the incidence and severity of disease. For me, its role is to reduce the likelihood that an infected dog will get seriously ill or die. That’s certainly useful, but vaccination is not a way to prevent flu from getting into a kennel or shelter, or spreading once it’s there.

While canine flu is highly contagious, it can be contained, with effort. We were able to contain it when it hit Ontario a couple times in 2018, with a lot of testing, communication, quarantine and probably a healthy dose of luck, to be honest. Sometimes, people take an “oh well, it’s here and there’s nothing we can do” approach. There’s almost always something that can be done -usually good ol’ basic infection control measures will go a long way.

Part of me thinks this is interesting and part of me wonders why it’s noteworthy. Let’s go with the first thought and consider the interesting aspects of a presentation at the recent ASM Microbe 2019 Conference, “79 cases of pet-associated Pasteurella multocida infections in a 30-month period with reports of novel modes of non-bite transmission and their significance,” as reported by Healio Infectious Disease News.

Pasteurella multocida is a bacterium that’s commonly found in the mouths of dogs and cats. So, not surprisingly, it’s commonly associated with bite infections. However, since it’s in saliva and exposure to dog/cat saliva isn’t uncommon, other routes of infection are possible. There are lots of case reports from things like dogs licking faces (causing ear infections) or wounds (e.g. cuts, diabetic ulcers, leading to wound infections), or infections of indwelling devices like feeding tubes and catheters (either from close contact of the animal with the insertion site or contamination of the person’s hands, resulting in contamination of the insertion site).  Anytime pet saliva reachs non-intact skin or mucous membranes (e.g. nose, mouth, eyes), there’s some, albeit low, risk of infection.

The conference presentation by Dr. Don Walter Kannangara described  79 cases of Pasteurella multocida infection in people over a 30 month period. 43% of those were not linked to a bite, which is a somewhat impressive number.

Twenty-nine cases were linked to cat bites, and 16 to dog bites. The rest had various assumed non-bite exposures, including:

  • Licking wounds or ulcers
  • A foot with a diabetic ulcer stepping on dog drool
  • “Falling down when drunk and contaminating abrasions with dog saliva” (Okay, that’s a new one for me)
  • “Epiglottitis (inflammation of a structure in the throat) after eating peanut butter and crackers that had been half-eaten by a dog” (Gross… also a new one for me)

The report has some interesting points but the take-home message remains unchanged: there is a variety of bacteria present in dog and cat saliva that can cause disease. It rarely occurs but it can, and it’s more common in people with wounds, compromised immune systems and the very young or very old.

  • Avoiding bites is obviously a key preventive measure.
  • Avoiding contact of dog and cat saliva with broken skin is another. The higher risk the person, the greater the required diligence in terms of avoiding saliva and responding promptly when there is contact (i.e.  washing).

A little common sense and hygiene go a long way.  Avoiding getting fall-down-drunk and not eating food partially consumed by dogs would fit into those categories as well.