Abstract:
Background. Although the prevalence of rheumatic heart disease in Ethiopia is one of the highest in the world,
the epidemiology of group A streptococci (GAS) in this country is little known. GAS typing is a hallmark of both
the epidemiology and understanding of diseases caused by these organisms. We have therefore conducted this
study to investigate the emm (M-protein gene) type distribution of GAS carriers among Ethiopian schoolchildren.
Methods. In the present study, we performed emm typing of 82 GAS isolates collected from the throats of
healthy schoolchildren (6–14 years of age) residing in 3 different urban sites in Ethiopia: Addis Ababa, Gondar,
and Dire Dawa.
Results. We report high diversity of GAS isolates recovered from healthy schoolchildren. Eighty-two isolates
represented 43 different sequence types. Thirteen newly described subtypes were detected in this study. Of the
emm types prevalent in the study communities, 46% were not included in the 26-valent GAS vaccine.
Conclusions. The high diversity of emm types encountered within 3 months of collection suggest that production of a vaccine candidate based on the M-protein amino termini appears to be impractical for this population.
We suggest that investigations of other vaccine candidates, including the C5a peptidase, GAS carbohydrate, and
fibronectin-binding proteins, as well as conserved M-protein region vaccines, should be intensified to address the
needs of this population.
