I’ve written a lot in general about the risks of rabies and other infectious diseases from imported dogs. However, we have to remember that borders are political, not biological, and that rabies (like certain US presidents) doesn’t respect such borders, whether they’re between countries or between provinces.
Whenever we move animals or people, we risk moving diseases with them. In 2021 and 2022, we detected two rabid dogs in Ontario that were both imported from Iran. However, there are also risks with movement of people or animals from different risk areas within the same country, particularly very large countries like Canada. Arctic fox-variant rabies is present right across the north in Canada (see map below), and there is always a risk of it spilling over into dogs in northern communities. Then sometimes, those dogs get moved south and bring rabies with them. It’s happened before, and it’s just happened again, this time involving a dog from Nunavut that was moved to Winnipeg MB, where is subsequently developed rabies. Here are some of the highlights of the case:
- A 1.5-year old dog in a community in Nunavut was seen chasing a fox, along with some other dogs (which is not an unusual occurrence in the north) on February 27. It wasn’t clear (or at least not reported) whether there was any direct contact with the fox. If a dog has contact with an unusual fox and/or there is a chance the dog was exposed to saliva from such a fox (which is how rabies is transmitted), the typical recommendation would be to keep the dog under observation or confined for up to 6 months depending on its vaccination status and whether it’s able to receive a rabies vaccine within 7 days of the exposure. However, this isn’t always feasible in northern communities where dogs are often allowed to roam extensively and access to veterinary services and vaccines is very limited. It’s also important to remember that there is always a risk that dogs allowed outside unsupervised (even in the south) can have unobserved contact with wildlife, which puts them at risk for rabies exposure.
- The dog was then moved by a dog rescue group from Nunavut to Winnipeg on March 31 where it was quarantined for 2 weeks. This kind of quarantine after transport is a good general infection control practice for other disease that may come to light after the stress of travel, but it’s not long enough to rule out the risk of rabies. After arrival in Winnipeg, the dog was vaccinated against rabies and then spayed a couple of weeks later.
- The dog began showing signs of rabies on April 18, two days after the spay. Signs included hypersalivation, stargazing and aggression. It died two days later, and tested positive for rabies. Typing of the virus will presumably confirm the Arctic fox variant.
As is normal, there was an investigation to identify people and animals that might have been exposed to the dog during the short period when it would have been infectious (up to 10 days prior to starting to show clinical signs). “Several” people are receiving rabies post-exposure prophylaxis (PEP), including three who handled the dog when it was sick. Most likely, many of these people had little or no true risk of exposure, but understandably public health tends to very much err on the side of caution when it comes to rabies exposure in people.
It was reported that “One dog in the foster home received post-exposure vaccination but does not require a quarantine as it was fully vaccinated prior to its exposure.” That’s because if the dog was vaccinated and received a booster within 7 days of the potential exposure, it would typically only be subject to an observation period, which is much less strict than a quarantine or confinement period which is used for higher-risk dogs.
Two other related dogs were moved from the community over a six-week period, but they were transported at different times and had no contact with the affected dog since February. So while those dogs would have the same risk of exposure to an infected fox as any dog in the community, there was no increased risk due to exposure to the dog that developed rabies, because there was no contact during the dog’s potential infectious period (starting from approximately April 8).
We can’t eradicate rabies from wildlife across Canada, particularly in areas like the north where populations are so widely dispersed and often inaccessible. Wildlife-to-domestic animal contacts always carry some degree of disease transmission risk, and the risk of rabies is particularly high in endemic areas when reservoir species like foxes are involved. When we move at-risk dogs, we then create additional risks for others.
That isn’t to say we shouldn’t move dogs at all, as there are sometimes compelling and compassionate reasons to do so. But we need to take some basic precautions and always be aware of those risks. Ideally, we’d start by improving rabies vaccination of dogs in northern communities, which not only helps keep the dogs safe, but also protects community members who live in close contact with free-roaming community dogs. However, there are a lot of barriers to providing vaccination and other basic veterinary care in the North. Cases like this, and like the recent cases of confirmed rabid foxes in northern Ontario, highlight the importance of working together as a society to help overcome these long-standing barriers.
Distribution of rabies virus variants in Canada, 2016 to 2020 (Public Health Agency of Canada)