British champion rower Andy Holmes has died of leptospirosis, which was suspected to have been acquired from the water during the annual Boston Rowing Marathon on the River Witham (UK) in September. The 51-year-old Holmes, an accomplished Olympic rower from the 1980s, started to feel unwell in the days after the race, and developed a fever. He was subsequently diagnosed with Weil’s disease, a serious form of leptospirosis that can cause liver failure.

In some ways, this is being written off as a very rare and unfortunate event. It’s always hard to determine how aggressive to be when making recommendations about avoiding infections that can be acquired from common recreational and occupational activities.

The race’s welfare officer stated "Part of any rower’s training is being warned about water safety. If you fall into water you must wash thoroughly and if you think you have ingested any water seek medical advice." The problem is, exposure to water during rowing and similar events is basically unavoidable. Splashes of small amounts of water into the eyes, nose, mouth or cuts/scrapes could be enough to inoculate potentially harmful microorganisms into the tissues. People aren’t going to run to the physician after every potential exposure. Knowing whether or not the water source has previously been implicated in leptospirosis infections may be useful, but it doesn’t tell you anything for certain.

General recommendations for people working around water include:

  • Covering cuts and sores with waterproof bandages.
  • Washing hands, particularly before eating.
  • Avoiding contact of water with the eyes, mouth and nose, whenever possible.
  • Avoiding ingestion of any amount of water.
  • Ensuring their physician knows about the potential for water exposure should they become sick.

Obviously, complete avoidance of water exposure is impossible for many people, and the overall risk is very low. Weil’s disease is a rare condition but it does occur, both as sporadic cases and large outbreaks. It’s usually treatable but can be fatal, so it shouldn’t be dismissed.

Issues with pets and leptospirosis are similar. Pets, mainly dogs, become exposed from contact with water that has been infected by Leptospira bacteria from the urine of infected wildlife.  Infection can cause a broad range of disease in dogs as well, from subclinical to acutely fatal.  Vaccines for certain strains are available for dogs who are at higher risk of exposure.  Talk to your veterinarian about whether your dog should be vaccinated against leptospirosis.  More information about leptospirosis in dogs and cats is available on the Worms & Germs Resources page.

Image: Andy Holmes sits behind Steve Redgrave after winning a gold medal for Britain at the 1988 Seoul Olympics.

Veterinarians are reporting a potential cluster of leptospirosis cases in dogs near Lake Aquitaine in Mississauga (Winston Churchill Blvd. & Derry Rd. area). Leptospira gryppotyphosa has been confirmed in one dog, with other cases being suspected but not confirmed because owners declined testing.

Leptospirosis is a bacterial infection caused by different types Leptospira spp. These bacteria like to live in water and in moist conditions, and infections in dogs most often result in kidney disease. The bacterium is shed in the urine of infected animals. Leptospira gryppotyphosa is mainly found in wild voles, raccoons, skunks and opossums, and these animals can infect various environmental areas. Any animals exposed to outdoor environments in endemic areas can become infected from ingesting infected water or from contact of infected water with the mouth, eyes or nose, or cuts or other broken skin.

People in the area where these cases have been found should take particular care and probably avoid letting their animals wander into the water or wet areas. A vaccine is available to reduce the risk of leptospirosis, including disease caused by this Leptospira type. Vaccination of pets that are exposed to water or wet habitats in areas where lepto is present is a good idea. People in the Lake Aquitaine area should be particularly vigilant and vaccination of pets would be a good idea.

(click image for source)

Veterinarians are reporting an apparent spike in cases of leptospirosis in dogs in southern Michigan. Leptospirosis is considered a re-emerging disease in many areas of North America. This disease, caused by various types of the Leptospira bacterium, can affect many different species, including dogs and people. A wide range of illnesses can result, including fatal infections. In dogs, kidney failure is a common problem. 

Classically, leptospirosis is diagnosed in dogs that spend time in the woods and similar areas, where they may be exposed to the bacterium from contact with the urine of infected wildlife. Different types of Leptospira have different animal hosts, and infected hosts can shed large numbers of bacteria in urine. These bacteria can survive in wet conditions for long periods of time, and other animals can be infected through ingestion of urine-contaminated water or contact of urine-contaminated water with broken skin (e.g. tiny cuts or open sores on their feet) or mucous membranes (eyes, mouth, nose).

Michigan vets have suggested that the recent spike in cases is the result of local highway construction, which may have driven rats out of their normal habitats and into areas that people and dogs frequent. That’s possible, but it could also be increasing natural re-emergence of the disease, or increasing recognition of the disease, as more attention is being paid to it. Regardless, an understanding that this disease is a problem in the area is important to allow for prompt diagnosis (and proper treatment), as well as preventive measures.

A vaccine is available, but it is not 100% protective and only protects against certain strains of Leptospira. Nonetheless, it’s still a good idea in areas where disease is caused by the strains present in the vaccine and when dogs have a reasonable chance of being exposed.

People can also get leptospirosis. Most often, they are exposed just like dogs: from the outdoor environment. However, pet-to-human transmission has been reported, mainly involving pet rats (since rats are an important reservoir host). People who have contact with an infected dog must take precautions to reduce the risk of transmission. This includes avoiding contact with urine, good attention to personal hygiene (especially hand washing), and proper cleaning and disinfection of any areas potentially contaminated with urine. Prompt diagnosis of canine lepto is very important because treatment rapidly stops the animal from shedding the bacterium. The earlier it’s diagnosed, the quicker it can be treated, and the less contamination can occur.

More information about leptospirosis and Leptospira is available on the Worms & Germs Resources page, and in our archives.

(photo by costi)

When we have a -30C windchill and snow on the ground, my first thoughts usually aren’t about survival of bacteria in the outdoor environment. However, some microorganisms are well adapted for survival in various adverse conditions and we shouldn’t assume that cold=dead for every bug of concern. Along that line, we received a question recently about survival of Leptospira and I passed it along to our lepto expert, Dr. John Prescott. Here’s his guest post:

A reader in Ohio owns a dog that had leptospirosis, and had some questions about leptospirosis that may be of general interest.

Q1. Since the yard is likely contaminated with leptospires, she asked “How cold does the temperature have to get before the Lepto organisms are killed?

A1. Once it’s frozen, as it is now in January, they’re dead. Leptospires are fragile bacteria that are killed by dry heat and by freezing. They survive well in moist or wet environments, with moderate temperatures. In some countries leptospirosis is called “mud fever” or “fall fever” since this description captures so well the environmental conditions under which they thrive.

Although leptospirosis in dogs can occur at any time in the year, it mainly causes disease in the fall, late September to December, peaking in November. The increasingly mild and prolonged falls that we have experienced in the last decade are thought to be an important reason that leptospirosis has resurged in dogs. Interestingly, there is often a “blip” of leptospirosis in dogs in March in Ontario (and likely Ohio), since this is when the snow melts and conditions are wet, even though we can still get freezing at that time. I suspect that this is also the time when the raccoons that are thought to be the main source of leptospirosis for dogs are again active after the winter, and are foraging for food for themselves and their babies.

Q2. Do dogs still shed leptospires after they’ve been treated?

A2. No. Leptospires are quickly killed by the antibiotics used in treatment, amoxicillin or doxycycline. There is no danger that dogs treated for a week with these drugs are a risk to people or other animals. You may read in otherwise very reputable textbooks that these antibiotics “do not eliminate the carrier state” but I have no idea where this misunderstanding comes from.

Q3. Where can I find out more about leptospirosis in dogs?

A3. I like the web site, which is maintained by a vaccine company. I was surprised how many web sites devoted to leptospirosis that there are, but like much on the internet some contain highly misleading information. The “Worms & Germs” site has good past blogs about canine leptospirosis and is usually (just kidding, Scott) a reliable source of information.

One very common entrenched misconception, which is very hard to kill, is that vaccination does not stop animals shedding the organism. This is quite wrong. I suspect this misconception came from an experimental study half a century ago when dogs with pre-existing kidney infection with a leptospiral serovar called Canicola were vaccinated. It would not be expected by anyone that these animals would stop shedding since antibodies don’t penetrate into the place in the kidney where the leptospires live and from which they are shed in the urine. What vaccination does incredibly effectively is to prevent leptospires from actually reaching the kidney and setting up home there. The leptospires are removed by antibodies in the blood, so they never reach the kidney.

Back in the 1980s, Vietnamese Pot-Bellied Pigs were a popular fad pet.  These stout little oinkers are still out there, though they’re not quite as popular as they once were.  Potbellied pigs are cute (at least to some people… to each their own!), supposedly quite smart, and can even be house trained/litter trained.  As with any new pet though, it’s very important to do your research before going hog-wild and getting yourself a pot-bellied pig.  Talk to your veterinarian about what your pig will need in terms of medical care – vaccines, deworming, spay/neuter, hoof trimming, tusk trimming… Because they are uncommon pets, some veterinarians may not be comfortable treating a pig.  Make sure you ask ahead of time so you know to which veterinarian(s) in your area you can (and will!) take your pig.

We recently received a question about vaccination of pot-bellied pigs.  Just like dogs, in some areas pigs need to be licensed by the city, and certain vaccines are required in order to obtain a license.  In this particular case, pigs are required to be vaccinated against rabies, swine erysipelas and leptospirosis.  Regular visitors to this site are no doubt familiar with the issues around rabies and why it’s important to vaccinate for this deadly disease.  (More information about rabies is available on the Worms & Germs Resources page and in our archives.)  Swine erysipelas is a systemic bacterial infection caused by Erysipelothrix rhusiopathia, which can rarely cause a skin infection known as erysipeloid in humans.  This is not to be confused with human erysipelas, which is a skin infection caused by various species of Streptococcus (particularly Streptococcus pyogenes). 

But the question was about leptospirosis vaccination in pot-bellied pigs.  Pigs are susceptible to infection by Leptospira interrogans, just like dogs and people, and if infected a pet pig would be equally capable of shedding the bacterium in its urine and potentially transmitting the disease.  The issues around requiring vaccination of pigs for leptospirosis are very similar to those around making leptospirosis a "core" vaccine in dogs.  More information about this is available in the Worms & Germs post entitled "Should all dogs in Ontario be vaccinated for leptospirosis?"  A pet pig would likely be exposed to the same serovars of Leptospira as a dog kept in the same area, typically by coming in contact with urine from infected wild animals such as raccoons and skunks when they go outside.  However, the risk of exposure for a pig that rarely or never leaves the house would be extremely low compared to a pig that has outdoor access.  Another important consideration is whether or not the pig vaccine is against the same serovars that a pet pig, instead of a commercial pig, might encounter.  This will also vary depending on in what area the pig lives.  The Leptospira servoars pomona and bratislava are actually host-adapted to pigs.

It is also important to vaccinate an animal with vaccines that are labeled for use in its own species.  Vaccinating a pig with a vaccine meant for dogs could have unpredictable results – it may increase the risk of an adverse reaction, or it may not adequately stimulate an immune response, thereby leaving the pig essentially unvaccinated.  Your veterinarian can discuss the pros and cons of vaccination in your pet with the available vaccine products.

More information about leptospirosis is also available on the Worms & Germs Resources page.

From Guest Author Dr. John Prescott, Professor, Department of Pathobiology, University of Guelph.  More information about Leptospira and leptospirosis can be found on our Resources page.

The last decade has witnessed a surge in leptospirosis in dogs throughout much of North America. Ontario and Québec have been part of the surge, which is associated with two serovars of Leptospira, grippotyphosa and pomona.

The reasons for the dramatic increase relate to: 1. The apparent spread of infection in raccoons and to a lesser extent skunks; 2. A changing climate that favours prolonged survival of these bacteria outdoors in the milder fall temperatures; 3. Perhaps to a minor extent increased awareness of the disease by veterinarians. Gillian Alton, a Masters student at the University of Guelph, has shown that the increased infection rate observed in recent years appears to have leveled off, which may be the result of widespread vaccination.

Leptospirosis should be suspected whenever there is kidney or liver inflammation of unknown origin, particularly in the fall of the year. In 2007, there were about 80 positive and 170 suspicious cases in Ontario based on blood tests submitted to the Animal Health Laboratory (AHL), University of Guelph. Since not all such blood tests go through the AHL, it is likely that there would have been about 160 positive and 350 suspicious cases based on this testing throughout Ontario, and an unknown number of cases diagnosed by PCR (a DNA-based test). If one includes cases diagnosed based on clinical signs but without laboratory testing, and about half the suspicious cases as positive cases, then there may be about 400 clinical cases (i.e. cases where the animal actually gets sick) of leptospirosis in dogs occurring annually in Ontario. Clinical leptospirosis in dogs is a serious disease and this number, if the assumptions are correct, represents a high burden of infection.

Arguments for recommending the new 4-way leptospiral vaccines as a “core” vaccine (i.e. all dogs should be vaccinated) in Ontario are:

  1. The suggested size of the problem;
  2. The often serious nature of the disease;
  3. The zoonotic potential of the infection (a small number of human infections acquired from dogs have been recognized in Ontario and Québec in recent years);
  4. The ongoing widespread presence and sometimes large numbers of raccoons in suburban and urban Ontario;
  5. The diagnosis of canine leptospirosis throughout the province;
  6. The diagnosis of the disease in dogs of all types, not just the “male hunting dog” which is sometimes conventionally regarded as “high risk”.

Arguments against recommending the new 4-way vaccines as a “core” vaccine are:

  1. The sporadic nature of the infection, including the lack of exposure of some dogs to raccoons and other wildlife sources;
  2. The number of vaccine reactions associated with leptospiral vaccines (this is not a significant problem with at least one of the vaccines);
  3. The considerable confusion caused by the (almost certainly totally unfounded) suspicion that serovar autumnalis causes canine leptospirosis, but is not in the new vaccines;
  4. The lack of inclusion of serovar bratislava in the vaccine (although this serovar seems to cause only mild disease in dogs);
  5. The annual cost of revaccination.

The vaccine manufacturers have the responsibility to provide the supporting data on which a “core vaccine” recommendation should be based, by testing dogs in Ontario for exposure to the different serovars. In the absence of such data, but knowing the possible extent of the problem, veterinarians should always discuss the pros and cons of leptospiral vaccination with dog owners. My opinion is that, barring problems of vaccine reactions and hypersensitivity in individual dogs, annual leptospiral vaccination with a 4-way vaccine should be recommended.

A large and eagerly-awaited follow up study on adverse post-vaccination events in dogs was recently published recently, and it provides a lot of solid – but unsurprising – data.

The study (Moore et al. 2023), published in the Journal of the American Veterinary Medical Association and led by Dr. George Moore from Purdue, used medical records from a large corporate practice network in the US (Banfield) to study adverse events that occurred within 3 days of vaccination of dogs. In total, they had data from 4,654,187 dogs (quite impressive) from 1119 veterinary clinics.

Here are some of the study highlights:

  • A total of 31,197 adverse events were identified. That corresponds to a rate of 19.4 events per 10,000 vaccinations, or 0.19%.
  • Forty-five percent (45%) of vaccine reactions were classified as mild, while 15% were considered severe.
  • As expected, adverse events were more common in small dogs. The figure below shows the decrease in adverse events with increasing dog size.

We’ve known about this association for a while, and it still holds true. The highest rates of adverse events were in French bulldogs (55.9/10,000), dachshunds (49.4/10,000) and Boston terriers (44.9/10,000). The lowest risk breeds were mixed breed dogs (14.0/10,000), golden retrievers (12.6/10,000), Labrador retrievers (11.1/10,000… Ozzie and Merlin will be happy about that), German shepherds (9.2/10,000) and border collies (8.6/10,000).

Adverse events were also more common in younger dogs. Rates were 24.6/10,000 for 2-9 month-old dogs and 25.6/10,000 for 9-18 month-old dogs.

There was some variation in adverse event rates between different vaccine types, but nothing dramatic. Rabies vaccines had the highest incidence of adverse reactions, coming in at 24.8/10,000, just a smidge ahead of other core vaccines (i.e. distemper virus, parvovirus, adenovirus) for which the rate was 24.6/10,000 (see table below)

There are often unwarranted fears about (current) leptospirosis vaccines, likely based on historical issues since much older lepto vaccines seemed to cause more reactions. However, the incidence of adverse events with our current vaccines was lower than that for core and rabies vaccines (21.4/10,000).

When the researchers looked at moderate and severe reactions, rabies and other core vaccines had the highest risk. Lepto vaccines were associated with highest risk of mild reactions.

  • This shouldn’t be taken as indicating core and rabies vaccines are dangerous. Rather, it highlights that lepto vaccines are low risk.

As expected, adverse events increased with more vaccines administered at a single visit. Note that this refers to more vaccines, not more antigens (a core vaccine that covers parvo, distemper, adenovirus and paraflu is one vaccine). The figure below shows that. The increase for large dogs was pretty unremarkable but it was pretty clear for medium and small dogs.

Overall, none of the results are surprising. They fit with what we’ve known and observed for a while, but it’s great to have very solid data to back it up.

Vaccines save lives. There’s no denying that.

Vaccines can cause adverse effects. There’s also no denying that.

The low risk of adverse effects and the high risk (and implication) of these infectious diseases make the cost:benefit ratio very clear to me.


Vaccine hesitancy by pet owners has been in the news a lot recently, largely due to a recent study about the prevalence and consequences of vaccine hesitancy among dog owners in the US (Motta et al. 2023). The survey-based study reported 37% of respondents think vaccines can cause “cognitive issues, like canine/feline autism”, 22% think the risks of vaccination outweigh the benefits, and 30% think most dogs receive vaccines that are not necessary. A colleague and I wrote a commentary for the San Francisco Chronicle about how this kind of vaccine hesitancy among pet owners is a concern for both people and pet, especially if it results in reduced rabies vaccination coverage.

The survey by Motta et al. only scratched the surface of the issues. We need a lot more information about vaccine hesitancy to truly understand the problem, and to be able to properly address it, but it’s definitely a concern.

Vaccine hesitancy, in both people and animals, is a really complex area. I think we’ve tended to over-simplify the issue in the past by lumping people into really broad groups (e.g. “anti-vaxxer,” “cheap”) without properly investigating the reasons behind their actions. People who don’t want to use vaccines aren’t one homogenous group.

  • Some are hardcore, true “anti-vaxxers.” This is often driven by mistrust in the system or science, and it’s hard to address this group. You can’t convince someone to trust, and trying to throw more facts at them doesn’t help.
  • Most are “vaccine hesitant,” with concerns that are not unreasonable but may be misplaced, misunderstood or simply not adequately addressed. This is the group on which we should focus, because it’s the group with which we have the most potential to engage, address their concerns and hopefully alleviate those concerns.

A lot of people who are vaccine-hesitant are worried about adverse effects of vaccination. We have to be honest: adverse effects occur. There’s a basic level of risk that we accept when we use vaccines because of the broader benefits. I have no doubt that the core vaccines we currently use in pets do more good than harm. But, I also have no doubt that some harm can occur. I’ve seen it.

That’s tough messaging, because a lot of people don’t really care what happens to 99.9% of the population after vaccination. They care what happens to their individual pet. While we can never tell people that the risk is zero, we can explain what the risks are and try to put them into perspective, so they can make an informed cost-benefit decision.

To do that, we need to understand what the risks really are. What data do we have on vaccine adverse effects in animals?

A landmark study about adverse events in dogs within 3 days of vaccination was published in 2005 in the Journal of the American Veterinary Medical Assocaition (Moore et al, 2005). The authors studied medical records from over 1.2 million vaccinated dogs. Here are a few of the things they found:

  • An adverse event rate of 38.2/10,000 dogs (0.38%).
  • Adverse events were more common in smaller dogs and when more vaccine doses were administered. It’s important to note that this means doses of different vaccines (i.e. number of injections), not the number of antigens. A vaccine that contains 5 different antigens is still just one vaccine dose from the standpoint of adverse event risks.
  • Each additional vaccine increased the risk of an adverse event by 27% in small (<10kg) dogs and by 12% in larger dogs.
  • The highest adverse event rates were in dachshunds, pugs, Boston terriers, miniature pinschers and chihuahuas.
  • 1.7% of the reactions were anaphylaxis (the most serious kind of reaction). That corresponds to about 0.006%.

By vaccine, the adverse event rates were:

  • Injectable Bordetella: 15.4/10,000
  • Rabies: 24.7/10,000
  • DAPP (distemper, adenovirus, parvovirus, parainfluenza): 26.2/10,000
  • Leptospirosis: 28.8/10,000
  • Borrelia (Lyme disease): 43.7/10,000

The highest overall rate was when a combination of rabies and Borrelia vaccines was given (54/10,000). The very common combination of rabies and core vaccines (DAPP) resulted in a rate of 39.3/10,000.

A subset of these records were investigated further to look in more detail at the adverse effects.

  • Facial swelling was the most commonly reported problem (31%), followed by wheals or welts (21%), general itchiness (15%) and vomiting (10%). 
  • Collapse was noted in 1% of dogs with a reaction.

A similar study in cats (Moore et al, JAVMA 2007) looked at adverse reactions in 496,189 cats within 30 days of vaccination. The overall adverse event rate was 51.6/10,000 cats. As for dogs, the risk increased with the number of vaccine doses that were administered. Lethargy was the most commonly reported problem.

The canine study has recently been repeated. I haven’t seen the results published yet, but snippets have been reported, and some data were presented by Dr. George Moore at the 2022 ACVIM Forum.

  • They evaluated the records of 4.9 million dogs that were vaccinated at Banfield Pet Hospitals in the US from 2016-2020.
  • The incidence of adverse events linked to vaccination within 3 days of vaccination was 18.45 per 10,000 dogs (or 0.18% of dogs). That’s less than half the rate of the older study.
  • Dachshunds, Boston terriers, miniature pinschers, French bulldogs and havanese were over-represented, continuing to show the increased risk in small breeds. The higher risk for certain breeds (and consistency between studies over a 20 year timespan) suggests that there are possibly genetic factors that drive the risk.
  • Increased number of vaccine doses given at the same time increased the risk in dogs les than 20kg but not in dogs over 20 kg.
  • There were no significant differences between adverse event rates for DAPP, leptospirosis, rabies or Lyme disease vaccines, with rates ranging between 19.2-21.3/10,000.

With these numbers, we can pretty confidently say that adverse event rates are low in dogs, and the most recent study suggests that they’ve actually dropped. A reason for that is unclear, but it could relate to newer, more refined, vaccines.

So, while I’d never guarantee that someone’s dog or cat won’t have a vaccine reaction, we know the rates are low and we have ways to reduce the risk even further. If we had lower vaccination rates we’d have fewer animals with vaccine reactions (that are almost always transient) but a lot more animals with severe and potentially fatal disease (which can have permanent long-term consequences, even if the animal survives.

The cost:benefit calculation is clear to me.

Lyme disease vaccine is a non-core vaccine, meaning it’s not needed for all dogs in all areas. It’s an effective vaccine, and I’d consider it a reasonable vaccine to give to dogs in (or visiting) higher risk areas, especially when there might be owner compliance issues with tick preventive medication. Available tick preventatives are very good, but sometimes people forget to give them on time, so vaccination is a good backup plan for those situations and in areas where the risk of exposure is particularly high.

Lyme disease vaccines are a bit unusual, in that they are primarily aimed at vaccinating the tick, not the dog (strange as that sounds). They usually target two proteins on Borrelia burgdorferi , the bacterium that causes Lyme disease. One of those is outer surface protein A (OspA), which is “expressed” on the  surface of the bacterium when it’s inside the tick. After the tick has attached to a host (like a dog) for a while, the bacterium changes to make itself more adept at infecting animals. That results in a change in the outer surface protein from OspA to OspC.

Lyme disease vaccines contain OspA, which induces the dog’s immune system to produce antibodies against that protein. When a tick starts to feed, it ingests the antibodies in the dog’s blood, which attack the bacterium before it’s ready to migrate to the dog.

Lyme disease vaccines can also contain OspC, to target the bacterium in the tick as it starts to produce that protein, and provide backup protection if the bacterium happens to evade the OspA antibodies and makes it into the body.

With typical vaccines, if an individual is exposed to the bacterium/virus for which they’ve been “primed” by the vaccine, they then get an immune response boost to generate even more antibodies. However, that doesn’t really apply to Lyme disease.  Since the dog’s antibodies flow into the tick, there’s no extra immune boost because the bacterium isn’t yet in the dog’s body (so the dog’s immune system doesn’t get exposed directly). Decreased antibody levels in the dog therefore more directly correspond with decreased protection. There will be some booster effect with exposure to OspC if the bacterium makes its way into the dog, but ideally we’d like to stop the process before it gets that far.

Lyme disease vaccines are given as an initial series of 2 doses, 2-4 weeks apart, and then an annual booster. But,  there’s concern that immunity from Lyme disease vaccines doesn’t last as long as others, so there’s less leeway for overdue dogs. It’s been recommended to re-start the 2 dose series from scratch if the dog is overdue for it’s yearly booster by more than 1 month. That’s pretty conservative, but it’s fair to assume that this vaccine’s long-term protective effect could be less predictable and solid than leptospirosis vaccines (where we accept up to 3 month delay).

Based on that, when it comes to Lyme disease vaccines, if a dog gets its:

First dose, but is late for the 2-4 week booster

  • Restart the whole series (i.e. 2 doses 2-4 weeks apart, then yearly)
  • We don’t have good guidance on what constitutes “late” or “overdue” here.  The American Animal Hospital Association vaccination guidance says within 6 weeks of the first dose is still okay, and that’s reasonable. It’s quite possible that the dog would respond well to a later booster, but we don’t have confidence in that.

First dose, 2-4 week booster, and then a yearly booster not more than 1 month late

  • Continue with the single annual boosters

First dose, 2-4 week booster, but is more than 1 month late for the yearly booster

  • Restart the whole series (i.e. 2 doses 2-4 weeks apart, then yearly)

As I mentioned above, tick prevention is still key, particularly for unvaccinated or inadequately vaccinated dogs. If vaccination has lapsed, it’s even more important to avoid ticks, do tick checks and use a good tick preventive medication (on schedule).

Lots of things you can get at a convenience store aren’t great for your health, but I wouldn’t have thought we’d have to add rabies to the list of concerns.

Public health officials in Niagara Falls, NY, are trying to track down nine baby raccoons that were handed out by someone outside a 7-Eleven store. Rabies is the big concern, raccoons being an important rabies reservoir species in this area. However, the list of potential diseases that could be transmitted by these raccoons is longer than that, with leptospirosis and the raccoon roundworm (Baylisascaris procyonis) being two other important issues.

As of the last report I saw, seven of the nine (too bad there weren’t eleven… that would have been funnier to report) baby raccoons had been recovered.

The list of reasons that handing out (or accepting) baby raccoons is bad is long, but to name just a few:

  • Wildlife belong in the wild.
  • Often, “rescued” baby wildlife are actually animals that were perfectly fine and temporarily left alone by their parents. Baby wildlife rescued by the public rarely survive and make it back to the wild.
  • Possession of wildlife is illegal in many areas, including New York state. Only licensed wildlife rehabilitators can posses wildlife, so that they are cared for properly and, when possible, re-introduced to the wild.
  • Baby raccoons are cute. However, they grow up to be large, curious and destructive adult raccoons that often end up being abandoned – but then they think they belong with people which makes them even bigger nuisances.
  • Baby raccoons rescued by members of the general public are often handled a lot in the process, leading to a lot of potential rabies exposures.
  • Wildlife belong in the wild.

More information about rabies (as well as leptospirosis) can be found on the Worms & Germs Resources – Pets page.