Source: The Cat Support Network
FIV stands for Feline Immunodeficiency Virus. It's a lentivirus, meaning that it progresses very slowly, gradually affecting a cat's immune system. It is passed through blood transfusions and through serious, penetrating bite wounds - mainly by stray, intact tomcats. The most well-known lentivirus in humans is HIV. But the two are not at all the same, and you can't get FIV from a cat. In fact, the only thing about FIV that you can catch is a bad case of the rumors!
FIV Facts (by Kristi Littrell)
1. The Feline Immune-deficiency Virus is a slow virus that affects a cat's immune system over a period of years.
2. FIV is a cat-only condition and cannot be spread to humans or other non-felines.
3. FIV cats most often live long, healthy and relatively normal lives with no symptoms at all.
4. FIV is not easily passed between cats. It cannot be spread casually - like in litter boxes, water and food bowls, or when snuggling and playing. It is rarely spread from a mother to her kittens.
5. The virus can be spread through blood transfusions, badly infected gums, or serious, penetrating bite wounds. (Bite wounds of this kind are extremely rare, except in free-roaming, un-neutered tomcats.)
6. A neutered cat, in a home, is extremely unlikely to infect other cats, if properly introduced.
7. Many vets are not educated about FIV since the virus was only discovered 15 years ago.
8. FIV positive cats should be kept as healthy as possible. Keep them indoors and free from stress, feed them a high-quality diet, keep and treat any secondary problems as soon as they arise.
Despite what many people think, cats with this condition can live perfectly long, happy, healthy lives!