Serotypes of group B streptococci in urogenital patients.

Isolates of group B streptococci (B-str.) of human urogenital origin were typed by a double diffusion precipitation test in agarose gel. The 114 isolates originated from normal women, gynaecological patients, women and men examined at venereological clinics, and were all typable by this technique. Type III/R was most frequently encountered (41/114), type Ic next (28/114), and then type II/Ic (18/114). Other types were: Ib (11/114), II/R (8/114), III (3/114), Ibc (3/114), II (1/114) and R (1/114). When the 4 groups of strains were considered separately a different pattern of distribution was seen in the gynaecological patients, in that 12/26 strains in this material were of type Ic. The Ibc protein antigen, which has been proved to be present also in streptococci other than group B, was widely distributed among the strains examined.