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When cats acquire FIV, their immune system begins to make specific antibodies against the virus. Vets diagnose FIV using a blood test that detects these antibodies in the infected cat’s blood. While a blood test is the standard medical practice, sometimes the test results require further testing for confirmation. For example, if the blood test comes back negative, there is a high chance the cat does not have FIV. However, here are a couple of scenarios where the antibody test might give the wrong diagnosis:

    1. A false-negative blood test result. The immune system takes 6 to 8 weeks to produce antibodies against FIV after infection. Therefore, an FIV-positive cat may be negative for FIV antibodies if they are infected very recently, and it is too early to test for antibodies. The cat has a negative blood test but is FIV-positive in this scenario.
    1. A false-positive blood test result. If the mother of kittens is FIV-positive, the breast milk from that mother contains FIV antibodies that can pass to the kittens. In this scenario, the kittens test positive for the antibodies passed from the mother, but the kittens themselves are negative for FIV. For this reason, vets recommend you wait to examine kittens for FIV until they are at least six months old and weaned.

Talk with your vet if your cat might fall into one of these scenarios. You might require a second test called the polymerase chain reaction (PCR). The PCR test checks for the viral DNA in the blood, as opposed to the antibodies, and will give a more confident negative or positive diagnosis.

How is FIV treated?

Proper management of FIV and close monitoring for secondary infections can help your cat live a healthy life for many years. Because FIV weakens your cat’s immune system, they are more prone to other illnesses, which can be dangerous if left unmonitored. Because of this, vets recommend clinic visits twice a year to test your FIV-positive cat’s blood and urine. This way, you can closely monitor your pet’s immune status.

Additionally, studies have shown that FIV is more likely to progress to feline acquired immune deficiency syndrome (AIDS) if the cats live in crowded, shelter-like conditions than in single or dual cat households. An increased number of cats in the house likely heightens the risk of exposure to bacteria or viruses that may cause secondary illnesses in FIV-positive cats. Making sure your pet has a spacious, low-stress environment is crucial to controlling the progression of FIV.

Your vet can use antiviral drugs to treat FIV, but your cat may suffer side effects associated with the treatment. Therefore, a vet may only suggest antiviral therapy if its benefits outweigh the side effects.

The above treatments and a well-balanced, nutritional diet are vital for an FIV-positive cat’s long-term health.

What does a positive FIV test mean for my cat’s quality of life?

If managed appropriately, an FIV-infected cat may live a long and fulfilling life. Even cats with severe immune suppression and secondary infections can recover with prompt and proper care. If you provide careful monitoring, management, and a healthy diet, your cat can live a great quality of life for years.

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Last Updated: August 21, 2022

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The following sources were referenced to write the content on this page:

Bęczkowski, PM, Litster, A, Lin, TL, Mellor, DJ, Willett, BJ & Hosie, MJ 2015, ‘Contrasting clinical outcomes in two cohorts of cats naturally infected with feline immunodeficiency virus (FIV)’, Vet Microbiol, vol. 176, no. 1-2, pp. 50-60.

Hartmann, K 2012, ‘Clinical aspects of feline retroviruses: a review’, Viruses, vol. 4, no. 11, pp. 2684-2710.

Hartmann, K, Wooding, A & Bergmann, M 2015, ‘Efficacy of antiviral drugs against feline immunodeficiency virus’, Vet Sci, vol. 2, no. 4, pp. 456-476.

Hosie, MJ & Lutz, H 2022, Schalm’s Veterinary Hematology, 7 edn., Wiley Online.

Hosie, MJ, Addie, D, Belák, S, Boucraut-Baralon, C, Egberink, H, Frymus, T, Gruffydd-Jones, T, Hartmann, K, Lloret, A, Lutz, H, Marsilio, F, Pennisi, MG, Radford, AD, Thiry, E, Truyen, U & Horzinek, MC 2009, ‘Feline immunodeficiency. ABCD guidelines on prevention and management’, J Feline Med Surg, vol. 11, no. 7, pp. 575-584.

Little, S, Bienzle, D, Carioto, L, Chisholm, H, O’Brien, E & Scherk, M 2011, ‘Feline leukemia virus and feline immunodeficiency virus in Canada: recommendations for testing and management’, Can Vet J, vol. 52, no. 8, pp. 849-855.

Ravi, M, Wobeser, GA, Taylor, SM & Jackson, ML 2010, ‘Naturally acquired feline immunodeficiency virus (FIV) infection in cats from western Canada: prevalence, disease associations, and survival analysis’, Can Vet J, vol. 51, no. 3, pp. 271-276.

The Pet Cancer Foundation’s medical resource for pet owners is protected by copyright.

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