Molecular epidemiology of Streptococcus pneumoniae serogroup 6 isolates from Fijian children, including newly identified serotypes 6C and 6D.

Multilocus sequence typing (MLST) was applied to all unique serotype 6C and 6D isolates and a random selection of serotype 6B and 6A isolates from nasopharyngeal swabs from Fijian children enrolled in a recent vaccine trial. The results suggest that Fijian serotype 6D has arisen independently from both serotypes 6A/C and 6B.