Genotypic characterization of Streptococcus infantarius subsp. coli isolates from sea otters with infective endocarditis and/or septicemia and from environmental mussel samples.

Pulsed-field gel electrophoresis (PFGE) was used to type 128 Streptococcus infantarius subsp. coli isolates from sea otters and mussels. Six SmaI PFGE groups were detected, with one predominant group representing 57% of the isolates collected over a wide geographic region. Several sea otter and mussel isolates were highly related, suggesting that an environmental infection source is possible.