Worms & Germs Blog

H3N2 Canine Flu in Florida

Posted in Cats, Dogs, Vaccination

The recent H3N2 canine flu outbreak centred around dog shows in Florida has led to the usual round of questions and concerns.

How many dogs have been affected?

  • 3 dogs at parkHard to say. Cases aren’t carefully tracked and it is reasonable to assume that the majority of dogs that developed influenza (especially mild disease) were never diagnosed. Testing costs money and often doesn’t change how a dog with respiratory disease is managed, especially in the midst of an outbreak where influenza is assumed to be the cause. Therefore, a lot of cases get presumptively diagnosed but not confirmed. We keep working on ways to better track diseases like this but getting uptake is a challenge.

Is this a sign of a new problem?

  • No. Canine flu has been around for a while, although H3N2 canine flu is a relatively new arrival to the US. The virus causes sporadic larger-scale problems (like this outbreak), but then tends to retreat back to being a low-level disease. Outbreaks are always possible with a flu virus when it gets into a dog population with lots of close contact and limited immunity (not previously exposed or not vaccinated). A dog show is a great mixing vessel for viruses like influenza. All it takes is one infectious dog to cause an outbreak that can spread rapidly, as opposed to an infected household dog that has far fewer opportunities to infect other dogs during the relatively short infectious period.

Should my dog be vaccinated?

  • There’s rarely a yes/no answer to this question. Vaccination decisions should be based on a risk assessment, considering the likelihood that your dog will be exposed and the implications of infection. Things that increase the risk/need would include:
  1. Known presence of circulating canine flu in the area.
  2. Planned travel to an area where canine flu is present.
  3. Regular or upcoming interaction with lots of different dogs.
  4. Regular or upcoming interaction with dogs from areas where canine flu may be present.
  5. Dogs that are at increased risk of complications following infection.
  • This last factor is something I think is often overlooked (and we don’t have a lot of data to go on). Influenza infection is usually relatively benign, but it can be serious. In humans, we know that certain groups are at increased risk of complications. The same presumably applies to dogs, although it’s less well defined. For me, I get concerned about dogs with underlying heart and respiratory tract disease that might not tolerate infection well. I’m also concerned about elderly dogs and dogs with diseases that compromise their immune systems. These are groups of dogs that probably also have fairly low vaccination coverage rates in general.

What should I do if I live in an area where canine flu is present?

  • Know what’s happening, as much as you can. If an outbreak is largely confined to show dogs, average pet dogs are at lower risk, but show dogs may still interact with pet dogs at parks and other areas. If there are anecdotal reports of dogs getting sick from parks or other routine contacts, that’s useful to know (even though you have to take those types of reports with a grain of salt).
  • If there is known flu activity in the area (or vague reports of coughing dogs without a diagnosis), consider keeping you dog away from other dogs for a while. Influenza usually burns through a population fairly quickly, so we’re talking about days rather than weeks, in most situations. The less dog-dog contact, the less risk of flu spreading. To maintain an outbreak, the average dog with flu must encounter and infect another susceptible dog during the fairly short time it is shedding the virus.
  • If your dog develops signs consistent with influenza (e.g. cough, runny nose and eyes, lethargy, decreased appetite), keep it at home and away from other dogs. If you need to take it to the vet, call ahead so they can make a plan to prevent exposure of other dogs (e.g. examine your pet outside, bring it right into an exam room or isolation to prevent it from mixing with other patients).
  • Talk to your vet about vaccination.

What should I do if I live in an area where canine flu is not present?

  • Pretty much the same list as above. “Not present” really means “Not present at the moment” or “Not known to be present,” since any dog you pass on the street could potentially be infected. The risks are obviously much lower in areas where flu activity hasn’t been reported, but disease reporting in dogs is pretty lax.

Can cats be infected?

  • Yes, although it’s much rarer in cats than dogs.

Is there a risk to people?

  • I should say there’s “no risk” since that makes my life easier, but the answer is probably more accurately “there’s virtually no risk.” Infectious diseases like to do odd things ,and while there’s no evidence that H3N2 is a zoonotic disease concern, I can’t say with complete confidence that there’s not a rare subset of people who would be susceptible (usually with mild infection). Most likely, lots of people have been exposed and some have had the virus enter their bodies, where their immune system took care of it with no problems. Rare mild disease may not be occurring or may easily be overlooked. The bigger concern is the potential for a dog or other species to be infected with H3N2 and another flu virus at the same time, creating a new virus that could be more virulent in people. This is always a concern, but the odds of this happening are very low. The fact that it’s past peak human flu season probably helps too, reducing the odds of a co-infection.

New Ontario Lyme Disease Risk Map

Posted in Cats, Dogs, Horses

To continue the map-posting binge that I’ve been on lately, Public Health Ontario has just posted their updated Lyme Disease Risk Areas map for 2017.  For comparison, you can still also access the 2016 map too, and you can see that the risk areas have indeed expanded somewhat, particularly in Eastern Ontario.

  • The estimated risk areas are calculated as a 20 km radius from the centre of a location where blacklegged ticks were found through active drag sampling.
  • While low, there is a probability of encountering blacklegged ticks almost anywhere in the province.
  • Within estimated risk areas, blacklegged ticks are mainly found in woody and/or brushy areas.

For more information about how these maps are generated and how areas are selected for active tick dragging, download the complete pdf document here, or check out the PHO Lyme Disease website.

Lyme_disease_risk_areas_map_2017 copy 2

Tick Tracker Update

Posted in Cats, Dogs, Horses

Our online Pet Tick Tracker continues to receive lots of submissions, so here are some interesting maps showing some of the preliminary information compiled so far.  The maps show where the ticks are being reported, but remember that they’re not necessarily reflective of the true overall picture, since it depends on who is reporting and who isn’t reporting. However, it’s still useful for looking for trends, e.g. where certain ticks are more common. We’re also looking for outliers, e.g. tick reports from areas where we don’t expect to find them.  Outliers can potentially be followed up with active tick surveillance to see what’s there.  Most submissions so far have been from Ontario, so I’ve only posted those maps.

Map 1: Dermacentor (American dog tick, green) and Ixodes scapularis (black legged tick, purple).

  • Here, not surprisingly, we see Ixodes predominating in eastern Ontario, with Dermacentor predominating around Toronto and to the west.

Derm Ixodes 0removed copy

Map 2: Hot spot analysis of Ixodes scapularis reports

  • This is an analysis of the data that shows “hot spots” – places where Ixodes ticks are under- or over-represented

hot spot ixodes with legend copy

More to follow. Please keep the submissions coming!  Visit PetTickTracker.


Rabies in Northern Quebec

Posted in Dogs, Rabies, Vaccination

Whapmagoostui-Kuujjuarapik_1695Two rabid dogs have been identified in Whapmagoostui, a Cree community in a remote region of northern Quebec. Rabies is very rare in dogs in Canada, and in recent years, much of the concern has revolved around rabies in dogs from northern communities. Rabies is endemic in Arctic foxes, and dogs can be infected from contact with such animal, and then act as a bridge for transmission to other dogs and people. Rabid dogs have also inadvertently been shipped to more southern regions of Canada as part of rescue programs.

Whapmagoostui, along the east coast of Hudson Bay, has many of the typical challenges of northern communities based on its remote location, with access only by plane or seasonally by boat, no veterinarian and a roaming dog population. The presence of packs of roaming dogs appears to be new, as indicated by public health officer Reggie Tomatuk in a CBC interview. “When I listen to our elders, they said to me ‘we never let our dogs loose in the community. That never happened before. It’s not just Whapmagoostui, but it’s all over the Cree Nation.”

While challenges in the north are different than in the south, the same big issues create risk, including unvaccinated, roaming animals. Increasing rabies vaccination coverage in dogs in the north is important but can be difficult and expensive. Reducing roaming and encounters with wildlife requires efforts in (and directed by) communities. These cases also highlight the need for care when transporting dogs, whether it’s importing from another country or from a region with different disease risks within the same country.

Bandicoots, Sandboxes and Salmonella

Posted in Other animals, Salmonella

800px-Perameles_gunniA playground in New South Wales, Australia, has been closed because its sandpit was linked to salmonellosis in two children. Sandboxes are a potential source of a few different infectious diseases since they can be used as litterboxes by animals such as cats, raccoons, and apparently, bandicoots.

In the Australian incident, two kids were diagnosed with salmonellosis and public health’s investigation presumably identified the sandpit as a common exposure. The kids were infected with Salmonella Java, a type that’s been found in various animals and has been linked to bandicoots in AustraliaSalmonella Java has previously been implicated as the cause of a sandbox-associated outbreak in Australia, along with an outbreak associated with beaches.

It’s not clear from the news report whether there was confirmation of the sandbox as the source. It says the sandbox was tested, but not whether it was positive. Given the Salmonella serovar and the sandbox link, it would be a fairly solid presumptive diagnosis even without a confirmed bacterial culture.

Prevention of sandbox-associated disease can be difficult, depending on the situation. Covering sandboxes is ideal, but not always feasible (and not an option for a beach, obviously). Additional protective measures such as paying attention to hand hygiene, supervising kids so they don’t put sand or sandy objects in their mouths (sometimes easier said than done!) and paying extra attention to hygiene if they are eating in/around sand make sense and are practical. These measures don’t remove all the risk, but zero risk isn’t a realistic goal.

More information about reducing the risk associated with sandboxes can be found in the Sandbox infosheet on the Worms & Germ Resources – Pets page.

Image: Eastern barred bandicoot, Australia (credit: JJ Harrison 2010)

PetTickTracker Update

Posted in Cats, Dogs, Horses

Dog in grassOver the years, we’ve tried a variety of new approaches to promote awareness (among the public, veterinarians and others) and to collect relevant research information. Some (like this blog) have taken on a life of their own and exceeded our expectations. Some didn’t go very far. Our most recent initiative is the PetTickTracker, a website designed to collect information about ticks found on animals. The goal is to raise awareness, see where ticks are being found currently, see if ticks are being reported in areas where they haven’t been in the past, and identify movement of new tick species in the area. This type of information can help inform where and what education campaigns might be needed, or identify specific areas where targeted tick dragging might be useful to follow up on interesting results.

That was the thought, at least.  It was launched two weeks ago, and I had no idea what to expect.

So far, we’ve had over 1100 responses… that’s way more than I thought we’d get, and great news. We’re in the process of looking at the data now, and hopefully we’ll have some mapping data to present soon. In the interim, here are some interesting tidbits:

  • Most reports were ticks from dogs, accounting for 84% of responses. That’s probably a reflection of their likelihood of exposure, their close observation by owners and the overall number of households with dogs.
  • The black legged tick (Ixodes scapularis) was most commonly reported, accounting for the majority of identified ticks. Dermacentor variabilis, the American dog tick, was the second most common. “I don’t know” was the next most common, showing how more tick ID education and resources are needed (there is a chart included on the PetTickTracker site itself).
  • The Lone Star tick (Amblyomma americanum) was reported 20 times in Ontario. That’s a tick type we’re watching in case it’s establishing itself in the province.
  • 70% were thought to be adult ticks. Age wasn’t certain for 22% of submission, and 8% were identified as nymphs.
  • Approximately 17% of animals had travelled over 20 km from home in the past 2 weeks. This shows how mobile out domestic animal populations are and how it’s possible for them to move ticks around between regions.

TickTracker short QR codeKeep the submissions coming! Access the PetTickTracker here, or copy the link below into your web browser, or scan the QR code with your smart phone. https://uoguelph.eu.qualtrics.com/jfe/form/SV_8pEFcT8xAEyK6hv



Human Rabies: Virginia

Posted in Dogs, Rabies, Vaccination

scruffy-puppyEvery few weeks I get a call or an email about travel-associated rabies exposure concerns. It’s usually from someone traveling to southeast Asia or India who has been bitten by a stray dog. Most of the time, it’s an unvaccinated person and the dog isn’t available for monitoring or testing. Since rabies is endemic in dogs in those areas and there’s no way to rule it out if the dog isn’t identified, it has to be considered a possible rabies exposure and is an indication for post-exposure prophylaxis (PEP). Sometimes PEP can be done in the country being visited, but often it’s done when the person gets home. In most situations, rabies exposure is best considered a medical urgency not a medical emergency. The incubation period for rabies is pretty long, and as long as PEP is started in a reasonable period of time, rabies is virtually 100% preventable. There are some situations where very prompt treatment is indicated, such as a bad bite to the head or neck, since rabies virus can move through the nerves to the brain much quicker in such a case given the close proximity.  With most exposures, there’s usually ample time to organize things and get home for treatment, often without needing to change travel plans.

Unfortunately, lack of awareness leads to rabies deaths. That’s a big problem in developing countries where the virus is endemic and thousands die ever year, but public awareness of what to do is still poor.

It’s also an issue with travelers. People often don’t go to travel clinics before visiting these regions or if they do, they don’t want to pay the rather expensive cost of pre-exposure rabies vaccination. Most often, they get away with it. However, travel associated rabies deaths occur occasionally.

A recent example is a person from Virginia who contracted rabies from a dog bite in India. I haven’t seen many details about the case, but I expect more information will come in the form of a CDC publication in the future.

Regardless, it’s a reminder that this disease is a major concern in many parts of the world, particularly areas in Asia, India and Africa. Vaccination isn’t cheap, but it’s a highly effective preventive measure for an almost invariably fatal disease.

It’s also a reminder that travelers need to know the risks and what to do. Without vaccination, rabies is still almost completely preventable if post-exposure prophylaxis is started, even weeks after exposure.

Thinking about things that can kill you isn’t at the forefront of people’s minds when planning a trip, but a little prevention can go a long way.

Pet Tick Tracker

Posted in Cats, Dogs, Horses

PHIL 22182 IxodesIt’s pretty clear that tick ranges are changing. In Ontario, we’ve seen movement of ticks into areas where they were never seen before, as well as potential changes in the types of ticks that are found in different areas. The potential for tickborne diseases like Lyme disease highlights the importance of understanding tick distributions. Knowing where ticks are helps determine the need for tick prevention practices, and knowing the types of ticks that are present helps determine what diseases need to be considered. As some tick species establish footholds in new areas, it’s important to recognize and communicate this as early as possible.  (Image shows a female Ixodes scapularis tick laying  her clutch of eggs, CDC Public Health Image Library 22182).

Various efforts are underway to track ticks and to figure out what pathogens they carry. We’re launching a preliminary project as well, the Pet Tick Tracker. This is a simple online tool where owners and veterinarians can enter information about ticks that they find on dogs, cats, horses or other domestic animals. This is the “lite” version for now – a slightly more comprehensive version that obtains a little more location information and includes a comment box will be released when it clear the University of Guelph Research Ethics Board. Stay tuned for that, but in the interim, people finding ticks on domestic animals can access it here:


The QR code below can also be scanned directly or printed off for future reference. With a QR code reader, a smart phone will be taken directly to the Pet Tick Tracker.

TickTracker short QR code


Modified Live Vaccines: Pets and Immunocompromised Owners

Posted in Dogs, Vaccination

Lately I’ve had a run on questions from veterinarians along the lines of “I have a client who is immunocompromised and their physician has said their pet should not receive a modified live vaccine. What should we do?

  • dog-nose-closeup There are a few different types of vaccines. Modified live vaccines are vaccines comprised of (as the name suggests) bacteria or viruses that have been modified to make them less virulent. They can be highly effective vaccines, as they help the immune system learn to defend the body from the normal bacterium/virus (in the same way) without having to handle the disease itself. They’re safe for normal individuals, but in immunocompromised people, these types of vaccines are typically avoided because the body still needs to “fight” the much less dangerous but still live vaccine version of the pathogen.

But what about pet vaccines?

There’s concern that giving a pet a modified live vaccine might result in a person being exposed to the same modified bacterium or virus.

But, what is the real risk?  We don’t know. However, when you think about what the issues really are, there are clearly some things to consider.

Is the “normal” bacterium/virus a problem in people?

  • If not, then the modified version won’t be a problem either. Most of the diseases we vaccinate pets against using a modified live vaccine are not caused by bacteria or viruses that can infect people, even at “full strength”. So, those vaccines are no concern at all.
  • If yes, it’s a tougher call. The main vaccine that causes concern is intranasal or oral administration of modified live Bordetella bronchiseptica, a bacterium that is one of the component causes of “kennel cough” (or more appropriately canine infectious disease respiratory complex (CIRDC)). This bacterium causes occasional infections in people. There are also a couple of reports of infections in people with the intranasal vaccine strain, but these cases either aren’t particularly strong or involve abnormal situations (such as accidentally being squirted in the eye with the vaccine).

What’s the cost-benefit?

  • If there is a potential risk, what’s the potential benefit? Does preventing disease in the animal reduce the risk to the person, because of the potential for exposure to the normal strain from the pet if it gets infected, or from the potential of being exposed to an antibiotic resistant bacterium if the animal gets sick and needs antibiotics? That’s a tough one to figure out, but certainly warrants consideration.

Is an animal vaccinated with a modified live bacterium a higher risk animal than any other animal?

  • This often doesn’t get considered. If you show me a dog vaccinated with a modified live vaccine and ask me to list the top things with which the dog is likely to infect a person, the modified live bug won’t even crack the top 10 (or 20). So, I can’t see how a dog that has been vaccinated really increases the infectious disease risk posed by a pet.

That doesn’t mean we should ignore the issue completely, since there are some things we can probably do to drop the already low risk even more. This mainly revolves around modified live Bordetella vaccination. A few simple, practical and logical measures would be:

  • Keep the high risk person out of the room when the animal is being vaccinated, to prevent high level exposure directly to the vaccine.
  • Wipe the face of the animal after vaccination to reduce the burden of the vaccine bacterium on the outside of the animal.
  • Avoid close contact with the animal’s face for a short period of time. Realistically, if someone is immunocompromised enough that they are concerned about vaccination of their dog, close contact with the dog’s face should be avoided at the best of times.
  • Encourage hand hygiene after contact with the dog. As above, that’s a good general precaution at any time, but can be emphasized during the day or two after vaccination.

New Guidance for Human Exposure to Rabies: Ontario

Posted in Cats, Dogs, Other animals, Rabies, Vaccination

This month, Public Health Ontario released a new Rabies Guidance Document for Healthcare Providers. It’s nothing particularly new but a good review of the recommended response to rabies exposure from various animal species, something that’s unfortunately often messed up or made more complicated than necessary. It includes some nice flowcharts, such as the one below. The full document can also be accessed via the PHO website.

1 copy 2