Epidemiology of Invasive Early-Onset Neonatal Sepsis, 2005 to 2014.

Background: Group B Streptococcus (GBS) and Escherichia coli have historically dominated as causes of early-onset neonatal sepsis. Widespread use of intrapartum prophylaxis for GBS disease led to concerns about the potential adverse impact on E coli incidence.

Methods: Active, laboratory, and population-based surveillance for culture-positive (blood or cerebrospinal fluid) bacterial infections among infants 0 to 2 days of age was conducted statewide in Minnesota and Connecticut and in selected counties of California and Georgia during 2005 to 2014. Demographic and clinical information were collected and hospital live birth denominators were used to calculate incidence rates (per 1000 live births). We used the Cochran-Amitage test to assess trends.

Results: Surveillance identified 1484 cases. GBS was most common (532) followed by E coli (368) and viridans streptococci (280). Eleven percent of cases died and 6.3% of survivors had sequelae at discharge. All-cause (2005: 0.79; 2014: 0.77; P = .05) and E coli (2005: 0.21; 2014: 0.18; P = .25) sepsis incidence were stable. GBS incidence decreased (2005: 0.27; 2014: 0.22; P = .02). Among infants <1500 g, incidence was an order of magnitude higher for both pathogens and stable. The odds of death among infants <1500 g were similar for both pathogens but among infants ≥1500 g, the odds of death were greater for E coli cases (odds ratio: 7.0; 95% confidence interval: 2.7-18.2).

Conclusions: GBS prevention efforts have not led to an increasing burden of early-onset E coli infections. However, the stable burden of E coli sepsis and associated mortality underscore the need for interventions.