The prevalence and persistence of group B streptococcal colonization among hospital personnel

A prospective study was performed to determine the prevalence and persistence of group B streptococcal colonization among obstetric (high-risk) and nonobstetric (low-risk) personnel. Seventy-four individuals participated in the study and the following sites were sampled: throat, rectum, vagina (females) and anterior urethra (males). The overall colonization rate was 32.4% and no statistical difference was found between high- and low-risk groups. The most frequently recovered serotypes were type III (37.5%) and type II/Ic (33.3%). Individuals older than 30 years were more likely to carry type II/Ic, whereas personnel in their twenties were most frequently colonized with type III. The rectum was the most frequently colonized site (83.3%). The vagina/urethra was colonized in 62.5% and the throat in 8.4% of carriers. Twenty-three culture-positive individuals were recultured from all sites three to six months later and persistent colonization was found in 56.5%. There was no statistical difference in persistence between the high- and low-risk groups. Type III carriers tended to become culture-negative, whereas type II/Ic carriers were significantly more likely to remain colonized with group B streptococci.