An insight into FIV in cats
FIV in cats is a condition similar to the virus that causes AIDS in people, although there is no risk of people catching AIDS from infected cats.
It infects the white blood cells of the immune system, killing or damaging them. A healthy immune system is needed to fight infections and monitor for cancer in the body; so infected cats have a greater risk of disease and infection from other viruses and bacteria.
Once a cat is infected, then infection is permanent. Just as in human HIV infection, carriers of FIV may show no symptoms of the disease for years. Between two to five per cent of the UK cat population is thought to be infected, but there is a lot of regional and local variation. Un-neutered male cats are more at risk.
What are the symptoms of FIV infection?
The symptoms following infection with the virus are usually mild. The cat may have a mild fever for a few weeks and there may be enlargement of the lymph nodes (the little lumps often referred to as “glands”). But often, cats infected with FIV appear completely normal.
Months or years later, as infection progresses, the cat may develop fever, lethargy, poor appetite and weight loss. Any recurrent illnesses may suggest that the cat has FIV – or another virus, such as FeLV .
Common signs include long-lasting or recurrent diarrhoea, a runny nose and sneezing (rhinitis), inflammations of the eye and recurrent skin infections. They are also more likely to get some types of cancer.
How do FIV cats get infected?
The virus passes from cat to cat in saliva, usually through biting in fights. Un-neutered male cats are considerably more at risk of getting FIV because a single bite may be enough to infect a cat. And a cat can be infected by biting an FIV-infected cat.
About one-quarter of the kittens born to an infected mother will be infected and there is a small chance that the virus can be transmitted through sharing food bowls and by cats licking each other during grooming.
How do you know if a cat is infected?
Infected FIV cats are identified by a blood test that looks for antibodies to the disease. For reasons not yet fully understood, these antibodies cannot fight off the infection. However, the commonly used tests are not completely accurate, and cats that test positive should be confirmed using a different test from a commercial laboratory. A few FIV cats that have the virus will test negative even though they are infected.
There are several other considerations with the blood test. It cannot be used for kittens under 20 weeks born to an FIV-infected mother. Some of these kittens will have antibodies from their mother to FIV but are not infected with the virus, and these antibodies interfere with the test. If it is not known whether the mother is infected, it is best to wait until a kitten is older than 20 weeks before testing.
In addition, it can take up to 12 weeks after catching the virus before the blood test can detect that a cat has the virus. Ifâ€¯you are worried that your cat is infected (for example, following a cat fight) you should wait for 12 weeks before testing. Finally, sick cats may not produce antibodies, so they may also test negative.
Is there a FIV cat vaccine?
There is no vaccine available currently in the UK. A vaccine is used in the United States, but it is not reliable and it does not work against all the types of FIV. It also poses problems for vets because a vaccinated cat will test positive for FIV.
How serious is it? Do FIV cats have to be put to sleep?
Recent studies have indicated that FIV may not reduce a cat’s lifespan, and cats may live for many years after being infected. However, it is unpredictable, as some cats develop severe and multiple infections. It is important to try and protect cats with FIV from catching other diseases, as they are more vulnerable than other cats. They should not be fed raw foods that might carry bacteria, such as raw eggs or meat, and it is better to keep them indoors. Hunting should be discouraged.