STUDIES ON THE RELATIONSHIP OF STREPTOCOCCUS HEMOLYTICUS TO THE RHEUMATIC PROCESS : II. OBSERVATIONS ON THE BIOLOGICAL CHARACTER OF STREPTOCOCCUS HEMOLYTICUS ASSOCIATED WITH RHEUMATIC DISEASE.

To determine the nature of the organisms associated with outbreaks of rheumatism at The Pelham Home, in a large number of individuals at the Presbyterian Hospital Nurses' Training School and among rheumatic subjects in New York City under continuous clinical observation, studies of the throat flora have been conducted. Hemolytic streptococcus in most instances appeared in the pharynx from 1 to 5 weeks before the onset of the rheumatic attack. These organisms have been investigated with the usual types of bacteriological tests and, in addition, have been classified serologically according to Lancefield's technique. The results have demonstrated that the organisms were not of a single type, but fell into six antigenic groups. The majority of the freshly isolated strains tested were strong toxin producers. The organisms producing the strongest toxin were cultures from the patients who developed extremely intense rheumatism. About 70 per cent of these toxins were neutralized by a monovalent streptococcus antiserum.