Feline Immunodeficiency Virus is a virus in cats that causes AIDS and is very similar to HIV in humans.
There is a long asymptomatic period prior to the development of AIDS where cats can live a relatively normal life.
Life expectancy of FIV+ cats is variable however most can expect to live an average lifespan.
FIV is most commonly passed through a bite wound that occurs during fighting.
These wounds often will form an abscess. An abscess occurs when an infected bite wounds heals over on its surface thus sealing the infection deeper inside.
An FIV+ cat may not have any outward symptoms if still in the asymptomatic period. Testing is offered at the annual health exam for most patients.
Because this virus is transmitted through bodily fluids and the likelihood of cat fights is so high it's best that FIV positive cats live indoors only.
This will help prevent the virus from spreading to other cats.