SEROLOGICAL RELATIONSHIPS BETWEEN SHIGELLA AND COLIFORM CULTURES

Abstract

The relationships between the O antigens of 33 known Shigella serotypes on the one hand and of 124 Escherichia coli O antigen groups and of certain coliform cultures on the other were studied. The O antigens of 10 Shigella serotypes are identical with those of E. coli O group cultures or with those of intermediate coliform bacteria. 17 additional Shigella serotypes bore a strong reciprocal O antigen relationship to E. coli O groups and coliform bacteria whereas two others are related to E. coli O antigen groups in unilateral, nonreciprocal relationships. Of 33 known Shigella serotypes, the O antigens of only 4 are unrelated to E. coli O groups or to O antigens of the coliform bacteria that were investigated. An additional E. coli O antigen group (124) was detd. during the investigation. The author calls attention to the need for further work on relationships within the enteric group of bacteria, emphasizing the importance to diagnostic work of such relationships as those descr.