Abstract
After an incubation period of weeks to months up to 14% of cats infected with feline coronavirus (FCoV) develop feline infectious peritonitis (FIP): a potentially lethal pyogranulomatous perivasculitis. The aim of this study was to find out if stopping FCoV faecal shedding with antivirals prevents FIP. Guardians of cats from which FCoV had been eliminated at least 6 months earlier were contacted to find out the outcome of their cats: 27 households were identified containing 147 cats; 13 cats were treated for FIP and 109 others shed FCoV. A 4-7 day course of oral GS-441524 antiviral stopped faecal virus shedding. Follow-up was from 6 months to 3.5 years: 11 of 147 cats died, but none developed FIP. No FIP-recovered cat relapsed. Cats from 8 households recovered from chronic FCoV enteropathy. A previous field study of 820 FCoV-exposed cats was used as a retrospective control group: 37 of 820 cats developed FIP: the difference was statistically significant (p = 0.0038). Conclusions: early treatment of FCoV-infected cats with oral antivirals prevented FIP. Nevertheless, should FCoV be re-introduced into a household then FIP can result. Further work is required to establish the role of FCoV in cats with inflammatory bowel disease.