Feline immunodeficiency virus in lions
Feline immunodeficiency virus (FIV) is a lentivirus that infects both wild and domestic feline species and is closely related to human immunodeficiency virus (HIV). Species-specific strains of FIV have been isolated from the domestic cat, puma, lion, leopard, and Pallas’ cat. In the domestic cat, the virus is present in blood and saliva, and biting is believed to be the most common way the virus is transmitted among the cats. Domestic cats infected with FIV develop changes in the numbers of T lymphocyte cells over a period of months to years, analogous to those seen with HIV/AIDS in people. While FIV infection is usually associated with abnormal T lymphocyte counts, this does not necessarily result in a compromised immune system. Some infected domestic cats develop clinical problems resulting in increased mortality, while others show no signs of illness and have a normal life expectancy