Serodiagnosis of Streptococcus pneumoniae infection in guinea pigs by an enzyme-linked immunosorbent assay.

Guineapig antibodies to Streptococcus pneumoniae (SPN) serotype 19F were detected by an enzyme-linked immunosorbent assay using a simple procedure. In experimentally infected hosts, antibody was detectable as early as 2 to 3 weeks after infection, and high titres were maintained for a long period. Antibodies higher than 1:64 were regarded as specific. In a field study, high antibody titres were shown in SPN enzootic colonies in contrast to negative or low antibody titres in a majority of the animals from non-enzootic and SPF colonies.