Last month, the Canadian Food Inspection Agency or CFIA officially declared a herd of cattle infected with bovine tuberculosis or bovine TB. An investigation spanning back six years has taken place, tracking the movements of the herd to limit the spread of bovine TB. Dr. Stacey Vos, veterinarian and Animal Health Regional Veterinary Officer with the CFIA, talks about the case itself, and the risks associated with bovine TB.
“What we know is that we had an animal that went to slaughter at the end of October (2024). When we did our slaughter inspection, we found some lesions that were compatible with bovine tuberculosis and were submitted as part of our normal routine testing and those tests did come back positive. At that point in time, we did an investigation of where that animal has most recently been and throughout its life, traced it back to a feedlot in Alberta where it had been for three and a half months, and it came from a farm in Saskatchewan.”
According to the CFIA’s industry notice, there have been three additional confirmed cases in the animals tested to date. All animals over twelve months of age will be tested to determine the prevalence of the disease, and the entire herd will be humanely depopulated.
There are serious risks associated with bovine TB, it’s a very easily transmittible disease within livestock, and can potentially spread to humans as the Mycobacterium bovis (M. bovis) is the same in humans. The spread is very rare from cattle to humans, something more prevalent in the early 1900’s. However, as Dr. Vos states, the risk of spreading to not just cattle, but other animals pose a great risk.
“Bovine tuberculosis is definitely a challenging disease. A big part of that is it's a bacterial disease and it hides within the cells. So, it's not like most diseases where they're maybe going through your blood, your immune system can find it and respond to it right away. They can hide from your immune system essentially. We really do see it in in cattle as kind of our main susceptible species, but it definitely can affect other ruminant species, sheep, goats. We see it in some wildlife populations potentially in elk and deer and that poses a greater risk for additional herds as it's a bit harder to manage in the wildlife."
For information about this specific case, visit the Canadian Food Inspection Agencies website, or for more general information about bovine tuberculosis and its risks, check out the CFIA’s fact sheet.