Vet school in US develops new B canis test

Researchers at a US vet school have developed a new test for Brucella canis that they claim is more sensitive and less prone to false positive results.

Cornell University College of Veterinary Medicine’s Animal Health Diagnostic Center has been offering the new canine Brucella multiplex (CBM) assay that measures antibodies in dogs directed against B canis antigens.

The average time to identify the disease in a dog is about six months, according to a paper published in the American Journal of Veterinary Research.

Quantitative assay

With the new CBM assay, vets can now monitor how well dogs respond to treatment for the disease because, unlike previous tests, the new assay is quantitative and can detect the level of antibodies in the serum of an infected dog – not just whether the antibodies are present.

Cornell researchers found that a decrease in antibody values directed against one of the two antigens in the CBM assay was associated with a resolution of the animal’s clinical signs.

That decline in antibodies, however, did not mean that the infection was no longer present because it could still be sequestered in the animal’s tissue.

Growing threat

Toby Pinn-Woodcock, assistant clinical professor in veterinary support services at Cornell, said: “We’re testing hundreds of dogs per month and we believe that this test is more sensitive and less prone to false positive results.”

B canis affects around 6% of dogs in the US and concerns have been growing in the UK about the scale of the threat posed by the zoonotic disease.

Dozens of cases of B canis were reported in the UK in 2022 – including the UK’s first known example of dog-to-human transmission – prompting calls for compulsory testing of all imported dogs, while Defra confirmed in January that a new review of its potential risks is under way.