Findings of serotypes of group B streptococci in human and bovine sources.

Five hundred and fifty-five strains of S. agalactiae of human or bovine origin were serologically typed. In human strains, serotype Ia was the most frequent irrespective of the source and kind of cultivation material, but serotype R was very frequent in urine. In bovine strains, one serotype was found as a rule in one stable both in small private and large socialist farms. The reason for such uniformity of serotypes is not known. Monocolonisation is one of the alternatives, but it seems more reasonable to assume that, the most resistant or more invasive strain will predominate in the herd in the course of time.