FIV

Feline immunodeficiency virus (FIV) is a retrovirus of the lentivirus genus that infects domestic cats and some wild felids. Infected cats may develop progressive immune dysfunction, leading to increased susceptibility to infections and certain cancers. FIV is not transmissible to humans or dogs. The virus is primarily spread through deep bite wounds from an infected cat; casual contact, sharing bowls, or mutual grooming generally does not transmit the virus. Vertical transmission from an infected mother to kittens can occur but is less common than bite transmission.

FIV occurs worldwide with varying prevalence depending on geography and cat populations. It is more often diagnosed in outdoor, roaming, and intact adult males due to fighting. Spayed or neutered indoor cats have a lower risk. The overall prevalence among owned cats tends to be low but can be higher in some groups such as those in shelters.

Clinical signs are often absent for years. When they appear, they relate to immune suppression and may include recurrent infections (skin, ears, eyes, upper respiratory tract), chronic gingivitis or stomatitis, weight loss, persistent fever, poor coat condition, and opportunistic illnesses. Neurological or systemic signs can occur in advanced cases.

Diagnosis is usually based on serology, detecting antibodies to FIV with ELISA or IFA tests. A positive result should be confirmed with a second test (e.g., another ELISA or Western blot) in some settings, because vaccination and maternal antibodies can affect results, especially in kittens.

There is no cure for FIV. Management focuses on maintaining health and preventing infections: regular veterinary care, dental care, a balanced diet, indoor living, and prompt treatment of illnesses. Some cats may benefit from antiretroviral therapy in select cases. Infected cats can live for many years with good quality of life. Prevention emphasizes reducing fights, screening new cats, and, where approved, careful use of FIV vaccination.