Feline immunodeficiency virus and feline leukaemia virus cause immune compromise that affects quality of life; understanding their management enables welfare-maximising decisions for affected cats.
FIV and FeLV positive cats require management that maximises quality of life while protecting negative cats from infection. The welfare of FIV-positive cats particularly is often better than anticipated — many live for years with maintained quality of life when secondary infections are managed promptly. The key welfare provisions are indoor-only housing to prevent further spread and additional infection risk, prompt treatment of secondary infections, and regular monitoring to detect immune deterioration early. Euthanasia decisions for virally positive cats should be based on quality of life, not diagnosis alone.