Feline immunodeficiency virus vaccine: a rational paradigm for clinical decision-making.

A veterinarian must take into consideration his/her responsibility to prevent disease when assessing the needs of a client's cat that is risk for FIV infection based on its established lifestyle. Cats infected with FIV have debilitated immune functions and exhibit a high level of chronic morbidity impacting on the animal's welfare and the owner's economic abilities to maintain the pet. Attempts to reduce the prevalence of FIV solely by advising clients to maintain their cats indoors has resulted in poor compliance and not impacted on a change in infection rates with outdoor cats. Therapeutics have not impacted on outcomes in infected animals. There has a need for a vaccine for high-risk cats. Options for vaccines that do not confound the current FIV antibody test have not been efficacious against a broad spectrum of isolates. Fel-O-Vax FIV, a conventional non-marker whole virus, has shown good efficacy against heterologous challenges. The intervention should be discussed with cat owners since the vaccine has a reasonable expectation of preventing FIV infection in cats at risk without undue safety issues. Veterinarians who do not initiate this dialogue with owners who have outdoor cats in an environment where 2.5% of cats in the USA are infected may be remiss in their professional responsibilities.