A direct fluorescent antibody test for identification of group E streptococci

A rapid and specific direct fluorescent antibody test was developed for the identification of group E Streptococci (GES). Tests for specificity included an inhibition test and application of the conjugate to smears of Staphylococcus aureus, Pasteurella multocida, and streptococci of Lancefield's groups, A, B, C, D, E (types I, IV and untypeable), F and G. With the inhibition test, a specific blocking reaction occurred and the conjugate cross-reacted only with group C Streptococci (GCS). Adsorption with GCS eliminated the cross-reaction and rendered the conjugate specific for GES.