Introduction
The feline immunodeficiency virus in cats can be diagnosed using a blood test which looks for antibodies that form as a result of FIV infection. These tests can either be performed at a veterinarian clinic, or the blood is sent to an outside lab.
Blood Tests
There are three different blood tests that can be used to detect FIV infection in cats: the IFA test, the Western Blot test, and the ELISA test. The ELISA ‘snap’ test can be used in a veterinary clinic, and the results usually only take 8-10 minutes. If the test is positive, or the results are unclear, than the blood is sent to an outside laboratory for the more accurate IFA or Western Blot blood tests.
When to Test
It can take up to 4 months for detectable levels of FIV antibodies to form in the blood after the initial infection occurs. For this reason kittens, and cats of unknown histories, should be tested at least twice for the disease. Cats that are in a high risk group for FIV infections, such as outdoor non-neutered male cats or cats that repeatedly fight with other stray cats, should be tested for FIV at least once a year.
False positive and false negative results can occur during routine FIV tests. Faulty results may occur due to: a broken or expired test kit, recent FIV vaccination, or if the cat or kitten was recently exposed to the virus but was not infected. All FIV positive tests should be confirmed with outside laboratory tests.