The Feline Immunodeficiency Virus (FIV) is a lentivirus, meaning that it progresses very slowly, gradually affecting a cat's immune system. The human equivalent of FIV is HIV.

To be a homeless cat with FIV can often mean a very long wait for a new home. There is a lot of unfounded fear and misinformation out there about FIV+ cats. Here are some reliable facts about FIV:

1. The Feline Immuno-deficiency Virus is a slow virus that affects a cat's immune system over a period of years.

2. FIV is a cat-only disease 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, unneutered 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.

http://www.bestfriends.org/theanimals/pdfs/cats/catfiv.pdf