With the recent increase in imported dogs to the UK, there has been a lot of discussion around policies regarding Brucella canis—a bacterial infection that affects dogs but can also be passed onto humans. While the risks for dog owners are low, veterinary staff are exposed to greater risk.
Below, we will not focus on discussing brucellosis as a disease but instead aim to understand the accuracy of the currently available tests.
Many owners may have heard about the SNAP test for B. canis, which was performed abroad before animals arrived in the UK. Without a proper understanding of the test’s accuracy, it’s difficult to comprehend why most veterinary practices do not accept it as proof of a truly negative
result.
The Limitations of the SNAP Test
The SNAP test is a quick and convenient diagnostic tool that detects antibodies against B. canis. While its speed and simplicity are appealing, it has notable drawbacks in terms of accuracy. Two critical factors in any diagnostic test are sensitivity (the ability to correctly identify those with the disease) and specificity (the ability to correctly identify those without the disease). Unfortunately,
the SNAP test falls short in both these areas for B. canis.
Sensitivity and Specificity Concerns
1. False Positives and False Negatives: The SNAP test can produce false positives, where the test indicates an infection when there isn’t one, and false negatives, where the test fails to detect an existing infection.
2. Variability in Results: The sensitivity and specificity of the SNAP test can vary
significantly depending on how the test is administered and the stage of the infection. This inconsistency makes it an unreliable standalone diagnostic tool.
Most o the SNAP tests available have a sensitivity of 70% and a specificity of 90%.
That means that they can not be used as a reliable diagnostic or screening test.
Why ELISA and SAT are Better Choices
Enhanced Accuracy
• ELISA: This test has higher sensitivity and is a more refined method for detecting antibodies against B. canis.
• SAT: This test detects the presence of B. canis by observing the reaction between the bacteria and the antibodies in the serum. It has been a longstanding method with proven reliability in diagnosing brucellosis. The SAT is particularly useful as it helps confirm the presence of the bacteria when used alongside other tests.
Using both ELISA and SAT together offers a comprehensive diagnostic approach. While ELISA provides detailed antibody information, SAT corroborates the presence of the bacteria. This dual approach minimizes the chances of misdiagnosis, ensuring your dog gets the correct treatment.
According to APHA, this approach gives an estimated diagnostic sensitivity and specificity of approximately 92% and 99%, respectively.
As a pet owner, knowing that the tests performed on your dog are accurate and reliable is invaluable. Relying on ELISA and SAT means you can trust the diagnosis and make informed decisions about your pet’s care. This comprehensive testing not only protects your dog’s health but also helps prevent the spread of B. canis to other dogs and humans.
Unfortunately, brucellosis is not a typical bacterial infection where a course of antibiotics should deal with the problem. It is a challenging disease that can lead to arthritis or inflammation of the heart muscles, just to name a few complications.
Trusting these proven methods is in your best interest, as it guarantees a clearer, more accurate understanding of your dog’s health. Since brucellosis is a zoonotic disease, veterinarians also play a crucial role in educating people about the zoonotic risk, especially those who are immunocompromised.
As a business owner, I am also responsible for the safety of my colleagues.
While we will never refuse emergency treatment to any animal, special precautions will be taken to limit risk to the veterinary staff that will increase price of the treatment or procedure.
For planned procedures, we will require ELISA and SAT tests.
To ensure it’s in both your and our veterinary staff’s best interest, we will not make a profit on performing these tests. Tests will be carried out at the official APHA price plus a small sample processing fee (such as appropriate packaging and postage).
If you already have some medical records for your pet and some screenings were done but you are not sure what they mean please don’t hesitate to get in touch with us, we are here to help.
If you wish to read more about the government guidance relating to Brucella canis, please visit: APHA Guidance on Brucella canis.