Feline Immunodeficiency virus is a lentivirus of the retroviral family, according to Cornell University. It is somewhat like human immunodeficiency virus in that it weakens the immune system and can cause AIDS-like symptoms. In the United States, 1 1/2 to 3 percent of healthy cats are infected with FIV.
Among cats infected with FIV, the feral, or free-roaming, are the more likely carriers, notes WebMD. This is because the virus is transmitted through deep bites, such as those that might occur in a fight between cats in an outdoor environment. Aggressive, male cats are also more likely to carry the virus for the same reason.
Symptoms of FIV include enlarged lymph nodes, fever, sneezing, and inflammation of the eyes, gums or mouth, according to the ASPCA. Additional symptoms include anemia, weight loss, an unkempt coat, a loss of appetite and behavioral changes. However, an infected cat can live without symptoms for many years. As a result, testing for the presence of the virus is an important component of feline veterinary care. Veterinarians utilize antibody tests that detect the presence of FIV antibodies in a cat's blood.
Veterinarians possess a vaccine for the prevention of FIV, but its effectiveness is uncertain as of 2015, and preventing exposure is the only sure means of preventing disease contraction, notes WebMD. Cat owners are advised to keep their cats indoors, away from any potential interaction with an infected feline.