Comparison of Serotypes of Group A Streptococci between Seoul and Chinju

Jung, Hyun Ju; Kim, Seon Ju; Kim, Yun Jeong; Maeng, Kook Young

Abstract

BACKGROUND: To interpret the serotyping data from group A streptococcal infections and their complications, serotyping data from healthy children are essential. In this study, we determined the serotypes of the strains isolated from the elementary school children located in Seoul and Chinju. METHOD: Eighty-two strains of group A streptococci isolated from Seoul and 76 strains from Chinju were serotyped with T typing, serum opacity reaction (SOR), opacity factor (OF) and M typing. T typing was undertaken by slide agglutination after trypsinization of bacteria, SOR and OF typing by microwell technique and M typing by Ouchterlony double immunodiffusion after Lancefield's extraction method.
RESULTS
In Seoul T 12 (52.4%), T 3 (9.8%), T 5 (8.5%) and T 27 (8.5%) were frequently encountered. In Chinju T 12 (44.7%), T 28 (13.2%) and T 6 (7.9%) were commonly identified. While M 12 (48.8%) and M 5 (14.6%) were most common in Seoul, M 12 (26.3%), M 22 (14.5%) and M 28 (10.5%) were widely distributed in Chinju. SOR positivity was 15.9% in Seoul and 54.0% in Chinju respectively.
CONCLUSIONS
The distributions of serotypes of group A streptococci between the two areas were more or less different. Serotyping of strains from healthy children may be considered as the basic data to understand the epidemiology of bona fide group A streptococcal infections and disease association of virulent strains.