Serologic studies of naturally occurring feline infectious peritonitis

Abstract

Serum antibodies to the feline infectious peritonitis (FIP) virus were measured in cats, using an indirect fluorescent antibody procedure. Antibody titers of 1:400 to 1:25,600 were seen in cats with both effusive and noneffusive forms of FIP. About 87% of the normal cats in FIP problem catteries and 20% of the cats in the Davis, Ca, area also had antibody titers to the FIP virus, ranging from 1:25 to 1:400. Although the infection rate is high among cats, relatively few of the cats infected with the FIP virus ever develop clinically apparent FIP.