[Type specific antistreptococcal antibodies in the passive hemagglutination test].

The authors present materials of the elaboration of a method of obtaining stable erythrocytic diagnostic agents from semipurified preparations of type-specific antigens of the hemolytic streptococcus of the 1st, 4th, 12th and 18th serotypes. Adequate specificity and high sensitivity of the passive hemagglutination test was shown in examination of the sera of experimental animals. In the sera of healthy children the type-specific antibodies were revealed with a different frequency at various seasons of the year; this was in inverse correlation with the level of scarlet fever morbidity.