Evaluation of emm gene types toxin gene profiles and clonal relatedness of group A streptococci

Abstract

Th e aim of this study is to evaluate antibiotic susceptibilities, emm gene types, toxin gene profi les and clonal relatedness of group A streptococci (GAS) isolates obtained from patients and carriers. A total of  clinical isolates from patients and  isolates from carriers were included in the study. Emm typing, toxin gene detection for speA, speB, speC, speG and smeZ genes and pulsed-fi eld gel electrophoresis (PFGE) was performed. Twenty-one distinct emm types were detected; the most common types were emm, emm, emm, emm, emm and emm. Th e detection rates of both emm types and the toxin genes didn’t diff er signifi cantly between patients and carriers. Th e presence of speA and smeZ was signifi cantly higher in emm and speG was signifi cantly lower in emm when compared to the other emm types. Th e rate of clustering obtained with PFGE wasn’t signifi cantly diff erent in patients and carriers. As a result, twelve of the  emm types detected in this study were covered by the -valent vaccine, constituting . of the emm typeable isolates; however the emm type which is one of the most common types in the present study is not among this coverage.