Distribution of Specific Types of Hemolytic Streptococci in Eight Hundred and Nineteen Cases of Infection

In two previous papers by two of us (L. A. R. and C. S. K.) and an associate 1 it was pointed out that hemolytic streptococci of groups A, B and C can be readily distinguished by the specific precipitin method of Lancefield 2 and that they also give distinctive types of hemolysis in standard poured blood agar plates. 1a Group A hemolytic streptococci are made up of a number of specific types, which may be distinguished by appropriate serologic methods. 3 For this purpose two procedures have been used. (1) the slide agglutination method of Griffith 4 and (2) the precipitin method of Lancefield. 2 Of the two, the slide agglutination method has had wider use. Most of the reports concerning the distribution of specific types of hemolytic streptococci in human disease have been made from England 5 and Australia, 6 but a few have appeared from Japan, 7 Germany 8 and the United States. 9 In