Group B streptococcal infection in Taiwan: maternal colonization and neonatal infection

Background: There is no national data on group B streptococcus (GBS) infection in Taiwan. We investigated incidence of maternal GBS colonization and neonatal GBS infection rate and clinical pictures of neonatal GBS infection to estimate the value of intrapartum chemoprophylactic strategy in Taiwan.

Methods: From January 2004 to June 2005, a prospective study to estimate maternal colonization rate by maternal rectovaginal culture at six hospitals was conducted. Neonatal GBS infection rate based on inborn infants was calculated retrospectively from January 2001 to June 2005; clinical pictures of infants diagnosed with invasive GBS disease were reviewed.

Results: Maternal colonization rate of GBS was around 20% at hospital base, incidence of neonatal GBS infection was 1 per 1000 live births of infants born at hospitals. There were 221 infants with GBS infection: in 142, the disease occurred within 7 days of birth (early-onset disease, EOD), and in 79, it developed later (late-onset disease). Infantile EOD was more often seen in mothers with premature rupture of membrane, often accompanied by respiratory failure necessitating ventilator support. Infants with late-onset disease often manifested fever, leukopenia, thrombocytopenia, and meningitis. Fifteen infants died, mostly of EOD type (12 of 15). Risk factors of mortality included rescue at delivery room, leukopenia, thrombocytopenia, sepsis, respiratory distress, persistent hypertension of newborn, respiratory failure needing intensive respiratory support (intermittent mandatory ventilator and high frequency oscillatory ventilator), surfactant use, shock, and congenital heart diseases.

Conclusions: We concluded that universal maternal rectovaginal culture of GBS with intrapartum antibiotic prophylaxis is an urgent call to reduce EOD and mortality because of GBS infection in neonates in Taiwan.