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Our oversubscribed CVMA webinar on the new US dog importation rules coming into effect on August 1 showed just how many questions are still out there about the changes. An FAQ is in the works that will help address many of these, so stay tuned for that.

The topic of this post is: why are they making these changes in the first place?

The current focus of most questions is obviously on the “what,” but I also get a lot of questions about “why.” I’m not sure there’s a great answer to that, but below are a few of the issues influencing the decisions.

Is importation of potentially rabid dogs into the US really an issue that needs to be addressed, especially in what seems like such a rushed manner?

Rabies is a big deal, no doubt about it. It’s estimated that about 50,000 people die of rabies every year internationally, the vast majority from canine rabies virus variants in places where the virus in endemic in feral dogs. It’s an almost invariably fatal disease, but it’s almost completely preventable even after exposure with prompt post-exposure prophylaxis. This makes it an interesting combination of a horrible but controllable disease – at least in areas where post-exposure prophylaxis is available and when people know they need to get it (those are usually the weak links everywhere).

Okay, rabies is a big deal. But is importation of rabies in dogs from places like Canada something that needs to be addressed?

Kind of. It’s been estimated that upwards of 1 million dogs travel from Canada to the US every year, but canine rabies virus variants (i.e. strains that spread within in the dog population) are not present in Canada. Dogs in Canada can get definitely get rabies, but this is usually from exposure to wildlife rabies virus variants that circulate in reservoir species like skunks, raccoons, foxes and bats. Overall, spillover infections like this causing rabies in dogs in Canada are rare, due to a combination of limited exposure of dogs to rabid animals (thanks to rabies wildlife control efforts) and some level of vaccine coverage in the dog population. The risk of rabies in dogs can be higher in some areas like northern communities where there is more exposure to reservoir wildlife species and less access to rabies vaccination for dogs. In 2023, there were three confirmed cases of rabies in dogs in Canada; two dogs from Nunavut and one from the Northwest Territories. So far in 2024, one dog in Manitoba has been confirmed to have had rabies.

So, we don’t have much risk from Canadian dogs, and realistically the risk is no greater than from any US dog. The concern is mainly around dogs imported from high-risk countries where canine rabies virus variant is circulating, including dogs that may be imported into Canada and then travel to the US. That’s a reasonable concern, but Canada also has reasonable controls to reduce the risk of importing rabid dogs (not great, but they’re getting better), so the risk of a rabid dog getting into Canada is pretty low, although two such incidents have occurred recently (both rabid dogs were imported into Ontario in 2021). Unfortunately, a massive number of exceptionally low risk dogs get caught up in measures that are very much erring on the side of caution, and are really just trying to address a few bad actors who try to skirt the rules and end up putting people and animals at risk.

Why won’t they allow importation of puppies less than 6 months of age?

Canada has pretty good controls on importation of puppies for commercial purposes (which includes resale and adoption), and on all dogs from countries that are high-risk for canine rabies (which were banned as of September 28, 2022). Unfortunately high-risk puppies can still cross the border as personal pets, all too often even when they’re not (e.g. rescue dogs for adoption, which should be classified as commercial). So, there’s no guarantee that a puppy in Canada didn’t just get off a plane from somewhere else and where it might have been exposed to rabies.

The question then becomes whether the US CDC can trust a Canadian veterinarian to attest that a puppy was born in Canada to a dog that is under their care. Yes, it requires some trust, but presumably a veterinarian falsifying such an attestation would suffer some pretty major repercussions, so it’s hard to imagine this would be a big risk. Remember: we should be aiming for maximum risk reduction, but that rarely equates to risk elimination. No protocol can 100% guarantee a rabid dog will never be imported into any country.

Why does there now need to be proof the dog has been in Canada for at least 6 months?

This is based on the assumption that if a dog came in from a high-risk country and was already infected with rabies, it would develop clinical signs (and die) within 6 months. That’s quite reasonable and is a well-accepted time period for incubation of rabies in dogs internationally, but even that is not a guarantee. In 2021, a dog was imported into Ontario from Iran that took just over 6 months to develop signs of rabies, but this was a very exceptional case. The 6-month time period also does nothing to address the risk of exposure to endemic wildlife rabies in Canada, from contact with skunks, foxes, raccoons or bats.

So, the 6-month limitation is largely to prevent “laundering” of high risk dogs through Canada, whereby they could otherwise arrive in Canada from a high-risk country an then shortly thereafter be moved to the US without disclosing the real country of origin. Fraudulent importation paperwork has been an increasing issue with dogs coming into the US, so the new approach brings in another level of scrutiny, as a veterinarian has to be involved in the process for at least 6 months. But what percentage of the risk from the million-ish dogs that cross the border each year would this really address? An exceptionally small one. Unfortunately, measures like these often get put in place to address uncommon or rare high-risk situations, and mostly end of causing problems for everyone else.

Does the 6-month requirement make sense?

The concept makes sense. The execution could be improved, since there are some major hassles with the current approach. If a dog doesn’t have a veterinary exam or other contact with a veterinary clinic documented in the 6-12 months before it is supposed to leave for the US, it can’t go. Even dogs that consistently visit the veterinarian every year would have large blocks on time when they couldn’t fulfill those requirements.  Some practical measures to improve the implementation could include extending the window beyond 6-12 months, and/or providing veterinarians with leeway to attest to the dog’s presence in Canada if they are confident about it, even if there’s no official record during the prescribed period.

Why is it a big deal if we import a rabid dog every once in a while?

That’s a fair question. There are lots of other diseases that impact people and animals, some of which can also transmitted from dogs. Rabies doesn’t crack the top 100 list of things that kill people or dogs in Canada or the US. Although I’d never dismiss the importance of rabies, we have to think of the cost-benefit for measures meant to address an exceptionally rare problem, that is importation of an infected dog into Canada with subsequent movement of the dog to the US within 6 months, and then transmission of rabies from that dog to people or other animals. These extensive measures, in terms of their application to dogs from Canada (vs dogs from high risk countries), address an exceptionally small subset of that problem. Focusing on proof of vaccination could be less disruptive and just as useful. It’s still no guarantee that rabid dogs won’t get across the border, because a dog can be vaccinated after it was exposed and still develop rabies, but once again we’re getting into very rare hypothetical situations.

The worst case scenario is that someone dies from rabies that they got from an imported dog. There’s also theoretically a risk to the population, if a rabid imported dog started a chain of transmission that led to canine rabies virus variant re-establishing itself in North America. That is very unlikely to happen, because it would require a large pool of unvaccinated dogs (or other canids) in reasonably close contact (i.e. high density) to maintain transmission. The infected dog would need to infect at least one other dog during the relatively short period that they are infectious before they die (usually 1-2 weeks). Since we don’t have a large population of feral dogs, have reasonable vaccine coverage in pet dogs, and have the resources to intervene aggressively to prevent spread (e.g. point-control vaccination response for wild and domestic canids), the odds of canine rabies re-establishing itself in dogs in Canada or the US are approaching negligible.

  • We can’t be quite as confident about avoiding canine rabies becoming established in wildlife in North America, but the risk is still really low. If an imported dog transmitted rabies to a wild canid (e.g. coyote), that canid would then need to pass it on to other canids. The host range and dynamics of canine rabies virus variant in other, non-domestic canids isn’t well understood. For example, there’s debate about the role of species like jackals in rabies virus transmission in Africa. It’s been suggested that the canine rabies virus that circulates in jackals only does so because there’s continued spillover from feral dogs. If there were no infected dogs, the virus would die out in jackals. If there was rare introduction of rabies from dogs into our wild canids, it’s pretty unlikely (though not impossible) that we’d see establishment of the new variant in wildlife. I’d rather avoid testing that theory, but it’s probably not a very realistic concern.

So why are they making such a big deal about this?

There are major direct impacts of exposure to a very limited pool of people and domestic animals from an imported rabid dog. That’s not inconsequential. It can take a lot of time and money to address cases like that, they cause a lot of stress for a lot of people, and if they’re not recognized and managed properly, they can result in devastating infections.

What about cats? They get rabies too.

There actually tend to be more rabid cats than dogs each year in Canada and the US, but globally dogs are the main concern. There’s no feline rabies virus variant, they are only infected through spillover transmission from other species. Nonetheless, cats are an important source of human infection. Is the risk of rabies from 10,000 imported dogs compared to 10,000 imported cats from the same region actually is probably higher in dogs, since the virus circulates more readily in dogs, but it’s certainly not a no-risk situation with the cats either.  The main difference in risk is probably the fact that we import substantially larger numbers of dogs. It’s not that cats pose no risk, they just pose less risk.

Do all these new measures make sense?

Yes and no. Rabies is a big deal. It’s rare in dogs in North America, but a single case causes a lot of problems and results in a lot of time and expense. There are legitimate concerns about importation of rabies in dogs.

But a lot of time and money is being burned and a lot of hassles are being created to address a rare problem (if that problem even exists). We have lots of human and animal disease issues. Is the time and effort spent on this issue a good investment? Probably not, at least not to the degree that’s required to implement these changes.

Canada’s Health Minister Mark Holland made a statement about the new requirements, in which he said, “Frankly, I just don’t think this is a good use of border officers’ time. There’s a lot of issues at the border. Whether or not my Maltese is another Maltese and having a border officer figure that out, I’ve said to [U.S. Health Secretary Xavier Becerra], doesn’t make sense to me.”

I’m not saying the new approach is useless. Some of the principles make sense, and tightening up some rules and loopholes is logical. However, it’s currently an overly cumbersome approach that brings in some complicated measures that don’t add a lot of value when it comes to applying them to dogs from Canada in particular, and many potential issues and unintended consequences are being encountered.