Serotyping and further characterization of group B streptococcal isolates from Indonesia.

Serotyping of 103 streptococci of serological group B isolated from human clinical specimens in Indonesia revealed mainly type pattern Ia/c and type patterns III and V, either alone or in combination with protein antigens c or R. Few cultures had serotype II and IV, none of the cultures had type antigen Ib or X. Extracts of one group B streptococcal culture reacted with antibodies specific to type antigens II, IV and R and one culture with antibodies specific to candidate type 7271. Protein antigen c was present as c alpha, c alpha, beta but not as c beta component. Group B streptococci with type antigen R grew generally as a granular sediment with clear supernatant, formed compact colonies in soft agar and reacted positively in the salt aggregation test. Group B streptococci without surface antigen R grew mainly with a uniform turbidity of the growth media, formed diffuse colonies in soft agar and were negative in the salt aggregation test.