Feline Immunodeficiency Virus (FIV)

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Feline immunodeficiency virus (FIV) causes a condition in cats similar to AIDS in humans. It infects the white blood cells, which damages them and therefore reduces the cat's ability to fight infections. There is no cure.

The human and feline viruses are different, so there's zero risk of humans catching AIDS from infected cats.

If your cat has just been diagnosed, you'll naturally be anxious and concerned for him. Try to take heart - many cats with this disease live long, happy lives.

The FIV virus is different to the cat leukemia virus. Some of the signs are similar, so the diseases are sometimes confused with each other.


Feline Immunodeficiency Virus - Common Questions And Answers

1) How do cats catch this disease?

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The virus is passed from one cat to another in saliva. This usually occurs through biting during a cat fight. An un-infected cat can get the disease if he's bitten by an infected cat. He can also catch it by biting an infected cat.

About 25 percent of kittens born to an infected mother will have the disease.

There's a small chance that the disease can be passed on through sharing food bowls, and by cats grooming each other.


2) How do I reduce the risk of my cat getting FIV?

The disease is nearly always spread during a male cat fight. The best way to protect your cat is to get him neutered. Neutering will greatly reduce his urge to fight, as well as curb other un-neutered male cat behavior problems.


3) What are the signs of the infection?

At the time of infection, the cat may develop a mild fever and swollen lymph nodes. However, some cats won't show any symptoms at all.

Months, or even years after being infected, the cat may start to get frequent infections and lose weight. Other common signs at this point may include:

(Also see feline leukemia symptoms, as a lot of these are similar to feline immunodeficiency virus symptoms).

Feline immunodeficiency virus is diagnosed by a blood test. However, this isn't 100 percent accurate - some cats will test negative even though they are infected. The test can't be used on kittens born to an infected mother until they're 20 weeks old. For advice on health insurance for your cat, click here.


4) Is there a vaccine available that prevents a cat getting FIV?

There's a vaccine available in the USA, but it doesn't work against all the different strains of the virus. There's no vaccine available in the UK.


5) My cat is infected. What do I do now?

Your vet will have a discussion with you when the diagnosis is confirmed. Things covered will include:

  • Keeping your cat indoors. This is usually recommended to prevent him from spreading the disease to other cats, and to help reduce the risk of him catching other infections. However, you may be able to let him out if you can confine him to your garden, for example.
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  • What to do if you have a multi-cat household. Your vet will likely recommend getting the other cats tested too. You'll then need to decide whether you keep the infected and non-infected cats apart. Some people choose not to separate them, because the risk of passing the disease on via food bowls and grooming is small. This is something you'll need to decide with your vet.


Cats with FIV can live happily and healthily for many years. In some cases, the disease doesn't reduce cat life expectancy at all. A good relationship with your vet, regular check-ups and prompt treatment of any infections will give your FIV-infected the best chance of a long, happy life.

See feline leukemia treatment for some advice on looking after your FIV cat (feline immunodeficiency virus and cat leukemia virus are different but their treatment is similar).



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