Molecular markers for throat and skin isolates of group A streptococci.

In summary, the emm chromosomal patterns distinguish between the two principal tissue site reservoirs of group A streptococci--the nasopharyngeal mucosa and impetigo lesion. Strains derived from normally sterile tissue sites are probably transmitted to new hosts by respiratory droplets, at least in the Connecticut population. The speA gene provides an example of how genetic exchange between different strains of group A streptococci may be limited to a single tissue site or to a subset of emm chromosomal patterns.