Is there concern about Brucella canis in Ontario?
- Yes. We have been concerned about this bacterium for a while, particularly in imported dogs and commercial breeders (including “puppy mills”). I can’t comment on the current situation more than to say we are investigating and I’m concerned but far from panicked.
- That said, this is probably not a new issue. A recent study from Michigan reported a low (0.4%) infection rate with B. canis in pet dogs, but much higher rates in commercial breeding operations (Johnson et al. 2018) and a study of dogs is Mississippi shelters found Brucella rates ranging from 8-9% (Hubbard et al. 2018). We know very little about Brucella canis in Canada, but it’s been here for a while at some level.
Why is B. canis a concern?
- This bacterium can cause disease in dogs and people. In dogs, most of the problems are reproductive, such as abortions, stillbirths and reproductive failure. However, a variety of other consequences can occur as well, even in spayed and neutered dogs.
- Human infections seem to be rare but they may be underdiagnosed, as signs can be vague and brucellosis might not be considered by many physicians.
Is Brucella in dogs treatable?
- We can use antibiotics to treat infected dogs, but it’s difficult to be confident that the bacterium is actually gone at the end of the treatment course. We end up having to periodically re-test dogs to see if there are signs of infection coming back. So, we can rarely say “yes, the infection has been cured.”
Do all Brucella-infected dogs need to be euthanized?
- In kennels, euthanasia is most often performed because of the risks of continuing to produce infected puppies and the potential for animals to keep infecting each other. Spaying or neutering is an important part of treatment in intact animals (since the bacterium likes to live in reproductive tissues), and that doesn’t work for a breeding dog.
- For pet dogs, it’s a case-by-case situation, depending on the disease, the household situation, risk aversity, and sometimes Public Health requirements.
What can I do to protect myself, my family and my dog from Brucella?
- If you are getting a puppy, make sure you know the source. Puppies from large commercial breeders, puppy mills or poorly managed operations are the highest risk because of how the dogs are sourced, managed and tested (or, more accurately, not tested).
- If you have a dog from an unknown source, you could consider testing it. It’s hard to say that Brucella testing is needed for every pet dog, but it is reasonable to consider if the dog might have come from a higher risk area (Asia, Mexico, southern US) or a large commercial breeder.
Is testing straightforward?
- No. It’s a multi-step process. Usually, we start with a screening test. If that test is positive, we follow up with a more specific test that is less likely to have false positive results. Then, we ideally follow up with a final test such as trying to culture the bacterium or detect its DNA using PCR. If the first test is negative, that’s great. If the dog might have been recently exposed, we’d ideally re-test in a couple months because it can take time for a dog to test positive after exposure.
Can my dog pick up Brucella at the park?
- Odds of this are exceptionally low. They’re probably basically zero, but in the infectious disease world, we’re rarely brave enough to say “never.” Brucella canis is transmitted most often in kennel situations, through breeding and through infection of pups before birth. Transmission can occur in other situations (e.g. a dog living with an infected dog) but that likely requires long-term close contact. Transient, casual contact (such as at the park) poses little risk.
What about my dog?
- My dog Merlin came from a breeder that we know well. He’s exceptionally low risk in terms of infection with Brucella. He’s neutered, which reduces the risk further. He has regular casual contact with dogs at Heather’s workplace but I’m not worried about that type of contact. I don’t plan on testing him or losing any sleep over his Brucella status. If I had obtained him recently from a puppy mill in Ontario, from out of the country or from unknown sources, I’d consider testing.
Here are a couple of additional good resources on B. canis: