STUDIES ON THE STREPTOCOCCI ("ENTEROCOCCI") OF LANCEFIELD GROUP D

Abstract

In the course of carrier studies on infants and on cultures isolated from infected persons in the same age group, a large number of strains classified as group D (Lancefield) were encountered. The frequency with which these strains were encountered, together with the relative scarcity of work done on this serologic group as compared with that on the Lancefield group A (in which the majority of organisms causing human infections are placed) seemed to justify analysis. The present interest in group D was further stimulated by the isolation of a strain of streptococci, originally misclassified as group E in another laboratory, from an infant with an acute, fulminating infection. It was not until rabbits had been immunized with this strain and reciprocal absorption tests had been done with the resulting serum and with known strains of the various serologic groups that the correct identity of this strain was established. The