Neonatal Group B Streptococcal Infection - Strategies for Prevention

Abstract

Group B streptococcal (GBS) sepsis is the commonest, serious perinatal infection in Western countries. Most of the estimated 500 cases and 100 deaths per annum in Australia are preventable by selective intrapartum antibiotic prophylaxis for women whose infants are at high risk. Routine antenatal screening for GBS vaginal carriage during pregnancy is the most obvious way to identify high risk pregnancies but, despite concerns about the medicolegal implications of not screening, it has not been universally accepted in obstetric practice in Australia. Reasons include the cost and poor predictive value of vaginal cultures, practical difficulties in implementation of protocols and potentially adverse effects of unnecessary administration of antibiotics to a high proportion of normal pregnant women. An alternative method of selection, based on clinical risk factors during labour and irrespective of GBS carrier status, would be less expensive and more practicable in settings in which antenatal care is provided in community or private practice or for women who receive no antenatal care. Only women with clinical abnormalities would be given antibiotics. Theoretically,at least as many cases of, and deaths from, neonatal GBS sepsis would be prevented by intrapartum antibiotic prophylaxis based on this strategy as by one based on antenatal screening for carriage. There is a need for this strategy to be carefully evaluated in practice.