Further studies on streptococci from scarlatina, erysipelas and puerperal fever
British Jour Exp Path 7(5): 286-293
Seventy-four strains were studied as to agglutination, ability to produce toxic filtrates with intracutaneous reaction in susceptible humans, neutralization of filtrates by antitoxic sera, and relationship between agglutination and toxin production. By agglutination 3 main groups were shown among hemolytic streptococci. The scarlet fever and erysipelas groups were confirmed and a similar grouping, though less clearly defined, was shown among puerperal strains. All strains from scarlet fever produced a toxic filtrate and similar filtrates were obtained from a large number of strains from other sources. All toxic filtrates, regardless of source, were neutralized by a high titer antitoxic, scarlet fever horse serum, though higher specificity was shown when antitoxic rabbit sera were used. Toxin production and agglutination by scarlet fever immune sera were not found to be closely related.