What is Feline Immunodeficiency Virus (FIV)?

Feline Immunodeficiency Virus (FIV) was first discovered in 1986 when cats started showing signs of immunodeficiency-like illnesses, similar to the symptoms seen in people with human immunodeficiency virus (HIV). In fact, FIV is classified in the same family of viruses as HIV. These viruses are all species-specific, meaning FIV cannot be transmitted from cat to human, and humans can’t transfer HIV to cats. Unfortunately, there is no treatment for FIV, and once infected, your cat will carry the virus for the remainder of his life.

What does Feline Immunodeficiency Virus do?

  • Hinders the cat’s ability to protect itself against other infections.
  • Cats may remain symptom-free for years before showing signs of illness.


How is Feline Immunodeficiency Virus spread?

  • Biting is the most efficient means of transmitting the virus.
  • Casual, non-aggressive contact does not appear to be an efficient way to transmit the virus.
  • It is occasionally transmitted from mother to kittens in-utero.


How common is the infection?

  • Estimates are that 1.5 3% of the cat population is infected


What medical conditions can be related to FIV?

  • Upper respiratory tract infection
  • Dental problems (inflammation of the gums and mouth)
  • Skin infections
  • Gastrointestinal symptoms (diarrhea)
  • Anemia
  • Enlarged lymph nodes
  • A variety of eye problems
  • Persistent fever
  • Seizures, behavior changes and other neurological disorders

In the early stages cats often exhibit no sign of the disease at all. A cat who is positive may progressively deteriorate or can have recurrent illness interspersed with periods of relative health.

How is the infection diagnosed?

  • The most common test is called an ELISA, can be done in a vet’s office, and takes about 10 minutes. It detects the antibodies sooner, but is less specific (may show false positives).
  • There is a confirmatory test called the Western Blot, which is sent to an outside lab, and results come back in 3-4 days. This test takes longer to detect antibodies at the beginning of an infection but is more specific, so a cat testing positive on the Western Blot is almost always truly positive.
  • Both of these tests detect antibody to the virus, not the actual virus.


What does a positive test result mean?

  • The cat is truly infected, OR
  • Very occasionally, there is a false positive result due to a defect in the test or the testing procedure. All positive results should be confirmed with a second test using a different format.
  • Kittens younger than 6 months may have received antibodies from their mother, but are not actually infected. Kittens testing positive should be retested until age 6 months to see if the test will become negative.
  • Cats that have been vaccinated against FIV may show a positive test result since the test detects antibodies developed in response to the vaccination.

What does a negative test mean?

  • The cat is not infected with FIV, OR
  • The cat is currently infected but was exposed recently enough that antibodies are not yetdetectable by the test. (Cats that may have been exposed should be tested again at least 2 months after the last chance of exposure.)
  • Occasionally, cats in the very late stages of the disease may test negative because their immune system is no longer able to produce antibodies.

How to prevent infection?

  • Prevent exposure to FIV positive infected cats
  • Keep cats indoors
  • To be 100% safe, adopt only infection-free cats into households with uninfected cats or house infection-free cats separately from infected cats (* Tree House does not discourage individuals from housing FIV and non-FIV cats together in situations where they are not likely to fight.)


What about the FIV vaccination?

  • Vaccines that protect against FIV are available.
  • Not all vaccinated cats will be protected.
  • Vaccination for FIV can interfere with future FIV test results (a negative, vaccinated cat will test positive because the test detects the antibodies created by the vaccination.)


What if one cat in a multiple cat household has tested positive for FIV?

  • Have other cats in the household tested for FIV.
  • Consider separating infected cats from non-infected cats to prevent transmission.
  • If there is no fighting or rough play among the cats the risk of infection in non-infected cats appears to be low, however, there is no guarantee that transmission will not occur.


How should FIV infected cats be managed?

  • Keep FIV positive cats indoors to prevent the spread of FIV and reduce exposure to other infections.
  • Spay or neuter infected cats.
  • Feed a nutritionally complete and balanced diet.
  • Avoid feeding raw meat, eggs, and unpasteurized dairy products.
  • Schedule wellness visits with your veterinarian at least every 6 months.
  • Closely monitor the health and behavior of the infected cat and discuss any changes with your veterinarian as soon as possible.


How long will an FIV infected cat be expected to live?

  • With appropriate care and treatment of chronic conditions, most infected cats can live for years.
  • If a cat already has experienced one or more severe illnesses as a result of FIV infection a much shorter survival time can be expected.


An FIV positive cat has died in a home, when is it safe to bring in a new, negative cat?

There is no waiting period as the virus does not live long outside the body and is killed easily. However, it is ideal for surfaces to be cleaned with a dilute bleach solution, especially if the cat had any secondary infections.

  • If there are other cats in the household, they should be tested to determine FIV status.


Can humans be infected with FIV?

  • No, the feline immunodeficiency virus infects only felines.