Feline coronavirus-naive cats that were immunized with a temperature-s
ensitive feline infectious peritonitis vaccine prior to entry into a l
arge shelter had a 75% reduced incidence of FIP over the subsequent 16
months compared to cats receiving a placebo. Vaccination did not caus
e accelerated disease and no unusual illnesses or deaths were associat
ed with the use of the vaccine. It appears, therefore, that vaccinatio
n may significantly reduce FIP losses if given according to the manufa
cturer's instructions to cats 16 weeks or older and prior to their int
roduction into environments with a known potential for FIP virus expos
ure.