Cat Feline Infectious Peritonitis and Welfare

Feline infectious peritonitis (FIP) has transformed from a uniformly fatal disease to a highly treatable condition following recent antiviral breakthroughs.

Key Facts

FIP is caused by a mutation of the common feline coronavirus causing systemic, inflammatory disease
Until 2019, FIP was considered almost universally fatal; it is now treatable in most cases
Antiviral drugs including GS-441524 achieve remission in over 85% of treated cats
Treatment involves 84+ days of daily medication — compliance and cost are significant welfare factors
Young cats under 2 years and those in multicat households are most susceptible

Welfare Considerations

FIP welfare has been revolutionised by antiviral treatment. Previously, affected cats faced rapid deterioration and humane euthanasia. The availability of effective antivirals has created an obligation to treat where possible. The welfare challenges now are primarily compliance — 84+ days of daily injections or oral medication is demanding — and cost, as treatment remains expensive. Cats that relapse after initial treatment typically respond to extended courses. The transformation of FIP from a death sentence to a manageable disease represents one of the most significant feline welfare advances in recent veterinary medicine.

What You Can Do

If your cat is diagnosed with FIP, ask your vet about antiviral treatment options
Explore compassionate access and lower-cost treatment pathways for FIP antivirals
Contact FIP support groups who can provide guidance on accessing treatment
Support research into lower-cost antiviral formulations for cats