FeLV, FIV, FIP TESTING FAQ

Arnold Plotnick DVM, ACVIM, ABVP
General Practice & Preventative Medicine

QUESTION

What is the earliest age you test cats for FeLV, FIV, FIP?

ANSWER

You can test kittens at any age. The FeLV test is an antigen test and is not affected by the presence of maternal antibodies. The FIV test, on the other hand, is an antibody test. Because antibodies in kittens are maternally derived, a positive test suggests that the queen was infected, and passed the antibodies to the kitten via the milk. Whether she passed the virus to the kitten cannot be determined. You must wait until the maternal antibodies have dissipated, and then retest. I recommend doing this for kittens that have tested positive when they reach six months of age. As for FIP, there is no point in testing for it, as there is no blood test that can reliably diagnose FIP (despite the claims of some diagnostic laboratories). A positive test merely means that the cat has been exposed to the enteric coronavirus and that there is a chance, although statistically very small, that the virus may mutate in the future, resulting in the disease that we call feline infectious peritonitis. The majority of kittens test positive for enteric coronavirus and never develop FIP.