Feline infectious peritonitis (FIP) was once universally fatal, but antiviral treatments have transformed outcomes for cats diagnosed with this disease.
Before antiviral treatments became available, an FIP diagnosis was a death sentence and cats were typically euthanized within days to weeks. Affected cats suffered from fever, weight loss, neurological signs, and fluid accumulation causing breathing difficulty. The transformation of FIP from universally fatal to highly treatable represents one of veterinary medicine's most significant recent advances. However, access to antivirals remains inconsistent globally, cost is prohibitive for many owners, and regulatory hurdles vary by country. Cats in regions without access continue to face unnecessary suffering and death.