MULTIPLE STRAINS OF STREPTOCOCCUS-PYOGENES IN SKIN SORES OF ABORIGINAL AUSTRALIANS

A molecular technique (random amplification of polymorphic DNA) was us ed to characterize group A streptococcal (GAS) strains among 194 isola tes from 55 swabs from 12 Australian Aboriginal children and adults wi th multiple pyoderma lesions, Ninety-three percent of the lesions cont ained only one strain of GAS, but 8 of 12 individuals were infected wi th more than one strain. We conclude that accurate epidemiologic surve ys require that more than one swab specimen be obtained from each pers on, whereas typing of more than one colony per swab is less informativ e, Characterization of GAS strains by random amplification of polymorp hic DNA analysis should help to provide important insights into the ep idemiology of GAS, particularly in tropical populations where many iso lates are M nontypeable, and into the mechanisms of genetic variation of GAS in such populations.