Feline immunodeficiency virus (FIV) weakens the immune system but is manageable. FIV-positive cats can live long, comfortable lives with appropriate care, indoor housing, and veterinary monitoring.
The welfare prognosis for FIV-positive cats is considerably better than their diagnosis implies to many owners. FIV progresses slowly over years, and many affected cats live normal lifespans before immune deficiency becomes clinically apparent. The most important welfare intervention is preventing secondary infections through indoor housing, regular veterinary monitoring, and prompt treatment of any illness. FIV-positive cats should be neutered, vaccinated for other respiratory and gastrointestinal diseases, and protected from stress. Euthanasia is not indicated at diagnosis — it should be considered only when quality of life becomes irretrievably poor due to untreatable secondary disease. Shelter organizations that euthanize FIV-positive cats routinely at intake are making an ethically unjustifiable welfare decision.