FeLV and FIV

Orange tabby cat

Feline Leukemia Virus (FeLV) and Feline Immunodeficiency Virus (FIV) are contagious, viral diseases that can damage the immune systems and cause cancers in cats. Even perfectly normal looking cats can silently carry these diseases.

FeLV is contagious through saliva, blood, or mother-to-kitten exposure. Unfortunately, 85 percent of cats with this disease die within three years of diagnosis. FeLV usually leads to life-threatening cancers and diseases caused by immune system suppression. 

However, cats with FIV — which is transmitted  through blood and sexual contact — can live very long and perfectly comfortable lives. To avoid FIV-related complications, cats with this disease should be seen by a veterinarian every two years (at least), and must receive immediate care when showing any sign of illness.

Neither FIV nor FeLV are transmissible to humans in any way.

Testing considerations

These diseases are rare. About 2.5 percent of the United States cat population would test positive for FeLV or FIV. When healthy looking cats were tested, the prevalence dropped into the 1.5 percent range. Stray cats that are getting into fights are the populations at highest risk.

There is no perfect test for either of these diseases. We run a “SNAP” test that looks for both diseases at once. If a cat was recently exposed to either of these diseases, it can take a month or sometimes more for them to test positive.

Animal Humane Society cares for at least 11,000 cats each year. Testing every cat is cost prohibitive, and keeping cats for at least a month or until 6 months old to avoid the need for retesting is counter to our goal of placing cats in good homes as quickly as possible. A longer stay would also put cats at risk of Infectious Respiratory Disease or other contagious disease.

Our testing policy

With the relative rarity of these diseases, the cost of testing, and the limits of the tests themselves, our policy is to test those cats where the results are reliable or we are most likely to find either disease. Cats with bite/fight wounds, pregnant or nursing cats, and those associated with a cruelty/hoarding case get FeLV/FIV tested.

Follow-up testing

Please consult with your veterinarian as soon as possible regarding potential FeLV/FIV testing. Together you can formulate a plan of testing and/or vaccination that fits you and your pets’ best interests. We advise you keep existing cats separated from newly adopted cats until you get a chance to discuss testing with your veterinarian and any recommended follow-up tests have been performed. This testing would be at the adopter’s expense.

For further information on these or any feline diseases, please visit the American Association of Feline Practitioners.

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