Cat Feline Infectious Peritonitis: Welfare in a Previously Fatal Disease

Feline infectious peritonitis was previously a fatal diagnosis but new antiviral treatments are transforming welfare outcomes for cats with this devastating disease.

Key Facts

FIP is caused by a mutated form of feline coronavirus and was almost universally fatal before 2019
Antiviral drugs GS-441524 and molnupiravir have achieved remission rates above 85% in treated cats
Treatment typically requires 84 days of daily antiviral medication and several months of monitoring
FIP primarily affects young cats under 2 years, causing immense suffering and early death without treatment
Access to treatment remains limited by cost and regulatory approval status in many countries

Welfare Considerations

FIP treatment represents one of the most dramatic welfare improvements in companion cat medicine in decades. A disease that caused virtually certain death within weeks now responds to treatment with high remission rates, allowing affected cats to live normal lives. The welfare transformation for treated cats is profound: from progressive deterioration and death to full recovery and normal lifespan. Access remains a welfare equity issue as treatment costs are substantial and regulatory approval incomplete in some jurisdictions. Organizations supporting affordable treatment access are addressing a genuine welfare gap that determines whether cats live or die based on owner financial resources.

What You Can Do

Learn the signs of FIP in young cats including weight loss, fever, and abdominal distension for early detection
Consult a veterinarian immediately if FIP is suspected, as early treatment improves outcomes
Support organizations providing financial assistance for FIP treatment for cats whose owners cannot afford care
Advocate for expedited regulatory approval of FIP antivirals in jurisdictions where they remain unlicensed