Meningococcal Group C Subgroup Determinant Detected by Immunofluorescence 1

Abstract

Summary

The presence or absence of a meningococcal Group C subgroup antigen (C₁₊) can be detected by immunofluorescence as readily as by a previously reported hemagglutination-inhibition method. When compared in strains isolated from cases and carriers, subgroup negative (C_1-) strains seemed to occur more often in cases. The subgroup antigen is widely distributed geographically. The characterization of meningococci by its presence or absence may be of value in epidemiological studies.