Epidemiologic Changes of Neonatal Early-onset Sepsis After the Implementation of Universal Maternal Screening for Group B Streptococcus in Hong Kong

BACKGROUND: The epidemiology of neonatal early-onset sepsis (EOS) has changed with time and with changes in prevention strategy. Population-representative contemporary data provide insights on how to further improve EOS prevention and triage strategies. METHODS: Neonates born in public hospitals in Hong Kong from January 1, 2006, to December 31, 2017 were included. The epidemiological characteristics of EOS and the use of intrapartum antibiotic prophylaxis (IAP) were compared between the 2 epochs before (January 1, 2006 to December 31, 2011) and after (January 1, 2012 to December 31, 2017) the territory-wide implementation of universal maternal group B Streptococcus (GBS) screening. RESULTS: EOS developed in 1.07‰ of live births (522/490,034). After the implementation of universal GBS screening, the EOS rate decreased in neonates born ≥34 weeks (1.17‰–0.56‰, P < 0.001) and remained similar in those born <34 weeks (7.8‰–10.9‰, P = 0.15), whereas the proportions of IAP coverage increased in both groups [7.6%–23.3% (P < 0.001) and 28.5%–52.0% (P < 0.001), respectively]. The major pathogen for EOS shifted from GBS to Escherichia coli, and for early-onset meningitis from GBS to Streptococcus bovis. IAP was associated with subsequent isolation of pathogens resistant to ampicillin [adjusted odds ratio (aOR) 2.3; 95% confidence interval (CI): 1.3–4.2], and second-generation [aOR 2.0; 95% CI: 1.02–4.3] and third-generation [aOR 2.2; 95% CI: 1.1–5.0] cephalosporins. CONCLUSIONS: Pathogen profile of EOS changed with the implementation of universal GBS screening. S. bovis has emerged as a more common pathogen associated with the risk of meningitis. IAP may not be as effective in reducing EOS rate among infants born <34 weeks as compared with those ≥34 weeks, and newer strategies may be needed.