Abstract: | A selective medium containing Todd-Hewitt broth, sheep blood, nalidixic acid, and gentamicin sulfate was found to enhance significantly the isolation of group B streptococci from vaginal cultures. Preparation of the medium, which is stable for up to 4 weeks at 4 C, is simple and inexpensive. Use of such a medium should facilitate identification of vaginal colonization with group B streptococci. |