Colonization, serotypes and transmission rates of group B streptococci in pregnant women and their infants born at a single University Center in Germany

Abstract

To evaluate colonization, transmission rate and serotype distribution of group B streptococci (GBS) in pregnant women and infants born in a single University Center in Germany. In a prospective study we collected cultures from pregnant women and ear cultures from newborns. We performed serotyping and susceptibility testing. Obstetrical factors associated with mother to infant transmission were analyzed using logistic regression. We evaluated cultures of 869 pregnant women and 845 neonates including 657 paired maternal-neonatal cultures. Maternal colonization occurred in 21.1% (183/869), transmission from mother to newborn in 11.2% (17/152). Intrapartum antimicrobial prophylaxis (IAP) and cesarean delivery were associated with reduction of transmission rate (P=0.014 and 0.019, respectively). The incidence for early-onset disease (EOD) was 1.71 per 1000 live births. Of GBS positive women IAP was administered in only 39% (59/152). Serotype III was the most prevalent isolate (28% maternal; 52% neonatal) and transmission occurred more frequently compared to other serotypes. The incidence of EOD and distribution of serotypes in Germany are similar to published data from the USA prior to 1996. Despite national guidelines with universal GBS screening, our study demonstrated a lack of adherence to this recommendation. There is a need for enhanced compliance.