What is Feline Immunodeficiency Virus (FIV)?

A Manageable Disease!

Virologists classify feline immunodeficiency virus (FIV) as a lentivirus (or "slow virus"). FIV is in the same retrovirus family as feline leukemia virus (FeLV), but the viruses differ in many ways including their shape. The specific ways in which they cause disease differ, as well. Here is an article on FIV by Best Friends Animal Society with which C.A.R.E. heartily concurs.

How common is the infection?

In the United States, approximately 1.5 to 3 percent of healthy cats are infected with FIV. Rates rise significantly-15 percent or more-in cats that are sick or at high risk of infection. Cats housed exclusively indoors are much less likely to be infected.

How is FIV spread?

The primary mode of transmission is through bite wounds. Casual, non-aggressive contact does not appear to be an efficient route of spreading FIV; as a result, cats in households with stable social structures where housemates do not fight are at little risk for acquiring FIV infections.

What does FIV do to a cat?

Infected cats may appear normal for years. However, infection can eventually lead to a state of immune deficiency that hinders the cat's ability to protect itself against other infections. These secondary infections are responsible for many of the diseases associated with FIV. Although, in our experience, many cats who are not FIV positive develop the same conditions as those who are.

What are the signs of disease caused by FIV?

Early in the course of infection, the virus is carried to nearby lymph nodes, where it reproduces in white blood cells known as T-lymphocytes. The virus then spreads to other lymph nodes throughout the body, resulting in a generalized but usually temporary enlargement of the lymph nodes, often accompanied by fever. This stage of infection may pass unnoticed unless the lymph nodes are greatly enlarged.

An infected cat's health may deteriorate progressively or be characterized by recurrent illness interspersed with periods of relative health. Sometimes not appearing for years after infection, signs of immunodeficiency can appear anywhere throughout the body. Signs can include:

Loss of appetite	Persistent fever
Poor coat condition	Persistent diarrhea
Enlarged lymph nodes	A variety of eye conditions
Pale gums and other mucus membranes	Inflammation of the mouth and gums
Infections of the skin, urinary bladder, and upper respiratory tract	Seizures, behavior changes, and other neurological disorders
Slow but progressive weight loss, followed by severe wasting late in the disease process

How is infection diagnosed?

Positive results
Because few, if any, cats ever eliminate infection, the presence of antibody indicates that a cat is infected with FIV. This test can be performed by most veterinary diagnostic laboratories and also is available in kit form for use in veterinary clinics. Since false-positive results may occur, veterinarians recommend that positive results be confirmed using a test with a different format known as the "Western Blot Test" results for which usually take a week or more to come in.

Infected mother cats transfer FIV antibodies to nursing kittens, so kittens born to infected mothers may receive positive test results for several months after birth. However, few of these kittens actually are or will become infected. To clarify their infection status, kittens younger than six months of age receiving positive results should be retested at 60-day intervals until they are at least six months old.

Negative results
A negative test result indicates that antibodies directed against FIV have not been detected, and, in most cases, this implies that the cat is not infected. Nevertheless, it takes eight to 12 weeks after infection (and sometimes even longer) before detectable levels of antibody appear, so if the test is performed during this interval, inaccurate results might be obtained. Therefore, antibody-negative cats with either an unknown or a known exposure to FIV-infected cats-such as through the bite of an unknown cat-should be retested a minimum of 60 days after their most recent exposure in order to allow adequate time for development of antibodies.

To further confuse the issue, we have had the experience of having an FIV negative cat become positive, remain positive for some years and subsequently become negative again.

How can I keep my cat from becoming infected?

The only sure way to protect cats is to prevent their exposure to the virus. Cat bites are the major way infection is transmitted, so keeping cats indoors-and away from potentially infected cats that might bite them-markedly reduces their likelihood of contracting FIV infection.

Vaccines to help protect against FIV infection are now available. However, not all vaccinated cats will be protected by the vaccine, so preventing exposure will remain important, even for vaccinated pets. In addition, vaccination may have an impact on future FIV test results. It is important that you discuss the advantages and disadvantages of vaccination with your veterinarian to help you decide whether FIV vaccines should be administered to your cat.

I just discovered that one of my cats has FIV. What should I do about my other cats?

Unfortunately, many FIV-infected cats are not diagnosed until after they have lived for years with other cats. In such cases, all the other cats in the household should be tested, as well. Ideally, all infected cats should be separated from the non-infected ones to eliminate the potential for FIV transmission. If this is not possible-and if fighting or rough play is not taking place-the risk to the non-infected cats appears to be low.

How should FIV-infected cats be managed?

Confine FIV-infected cats indoors to reduce their exposure to other infectious agents carried by animals, and to prevent the spread of FIV infection to other cats.
Spay or neuter FIV-infected cats.
Feed nutritionally complete and balanced diets.
Avoid uncooked food, such as raw meat and eggs, and unpasteurized dairy products
Schedule wellness visits with your veterinarian at least once every six months. Your veterinarian should pay special attention to the health of the gums, eyes, skin, and lymph nodes. A complete blood count, serum biochemical analysis, and a urine analysis should be performed at every examination. Additionally, your cat's weight should be accurately measured and recorded, as weight loss if often the first sign of deterioration.
Closely monitor the health and behavior of your FIV-infected cat. Alert your veterinarian to any changes in your cat's health immediately.

There is no scientific evidence that alternative, immunomodulator, or antiviral medications have any positive benefits on the health or longevity of healthy infected cats. However, some antiviral therapies have been shown to benefit some FIV-infected cats with seizures or stomatitis.

How long can I expect my FIV-infected cat to live?

It is impossible to accurately predict the life expectancy of a cat infected with FIV. With appropriate care and under ideal conditions, many infected cats will remain in apparent good health for many months or years. If your cat has already had one or more severe illnesses as a result of FIV infection, or if persistent fever and weight loss are present, a much shorter survival time can be expected.

All info is from internet sources and is for general informational purposes only. It is not intended as medical advice. C.A.R.E. is not a veterinary facility. Consult a licensed veterinarian if your pet exhibits any unusual symptoms or behavior.

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