I.                    The Feline Immunodeficiency Virus. What is it?

Feline Immunodeficiency Virus, or FIV, is a Retrovirus.    It is similar to HIV (Human Immunodeficiency Virus) and to FeLV (Feline Leukemia Virus), which are also Retroviruses.  Even though it is similar to HIV, there is no evidence at this time that FIV can infect humans.  It appears to be species specific.  The virus is found worldwide and can also infect exotic cats such as panthers and cheetahs.

FIV infection is most commonly spread through biting.  Grooming each other and sharing food and water dishes or litter boxes is much less likely to spread the infection.  Kittens can get FIV from their mother either before they are born or while nursing, but this does not happen very often.  Kittens can, however, get antibodies to FIV from their infected mother while nursing.

After a cat is exposed to FIV, usually through a bite wound, the virus multiplies in lymph nodes, lymphocytes (white blood cells), and salivary glands and spreads throughout the body.  This is the primary phase of infection.  During this time, the cat may have a fever and swollen lymph nodes or other subtle signs that may go unnoticed. 

After the primary phase of infection, there is a latent period of infection which may last for years.  During this time, the cat will not seem sick at all.  However, the virus is still present and it is still replicating in the body. The virus replicates in many different types of cells.  Replication of the virus causes a progressive decline in the immune function of the cat. 

Eventually, the cat may show symptoms of disease that are directly related to the FIV virus.  Because the virus has affected the cat’s immune system, it is not functioning normally.  Because of this, cat is much more susceptible to other infections and diseases and may also show signs associated with infection by other bacteria, viruses, fungi, or parasites.