Austin Pets Alive (APA) in Texas told PEOPLE that Sally suffered from suspected FIP — feline infectious peritonitis — “a once-fatal disease that APA has pioneered treatments for, giving cats like ...

Feline infectious peritonitis, first identified in 1963 ... only 10% of cases mutate into FIP, according to the Cornell Feline Health Center. At that point, the disease is often progressive ...

If it spreads within a population of cats, however, there is a chance it could mutate and cause a rare disease called feline infectious peritonitis (FIP). Important: A cat with FIP may display ...