Feline Immunodeficiency Virus (FIV)

ByIan Rodney Tizard, BVMS, BSc, PhD, DSc (Hons), DACVM, Department of Veterinary Pathobiology, College of Veterinary and Biomedical Sciences, Texas A&M University
Reviewed/Revised Aug 2018

    Feline immunodeficiency virus (FIV) decreases the function of the immune system of domestic and wild cats. FIV-infected cats are more like to acquire other types of infections that can affect other parts of the body, including the gums, mouth, digestive tract, urinary tract, and skin. They also have an increased risk of developing certain types of blood cancers. The virus is spread from cat to cat through saliva, primarily by biting. Cats that roam outdoors, male cats, and older cats are more likely to become infected. Shortly after becoming infected, cats may have a fever and enlargement of the lymph nodes (glands). However, these signs go away, and the cat may appear healthy, with no further signs of infection for months or years. However, once infected, cats remain infected for life, and most eventually have a deterioration of immune function and increased risk of other infections.

    Infection with feline immunodeficiency virus is diagnosed with a blood test that measures antibodies against the virus. Your veterinarian may recommend the test when you first adopt your cat, after exposure to the virus (for example, after a cat bite wound), or if your cat is ill. If your cat goes outside or lives with another cat that has the virus, your veterinarian may recommend that the test be repeated every year. Additional laboratory tests may be necessary if your cat tests positive for the virus.

    There is no effective treatment, but supportive care and treatment of signs is important. This includes visiting the veterinarian at least every 6 months, promptly treating secondary infections, providing a balanced diet, controlling parasites, and removing tumors. FIV-infected cats should be spayed or neutered. They should also be kept indoors to minimize exposure to infectious diseases and prevent the spread of the virus to other cats.

    A vaccine for feline immunodeficiency virus is available, but not all vaccinated cats will be protected, so preventing exposure is important, even for vaccinated pets. Vaccination may also have an impact on future feline immunodeficiency test results. You should discuss with your veterinarian whether your cat needs this vaccine.

    Although FIV has been called "feline AIDS" because of its similarity to human immunodeficiency virus (HIV), it is important to understand that FIV only infects cats and does not affect people.

    Also see professional content regarding feline immunodeficiency virus.

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