Early-onset neonatal group B streptococcus sepsis following national risk-based prevention guidelines

Aust N Z J Obstet Gynaecol. 2016 Feb;56(1):69-74. doi: 10.1111/ajo.12378. Epub 2015 Jul 14.


Background: Neonatal infection with group B streptococcus (GBS) is an important cause of infant mortality. Intrapartum antibiotics reduce early-onset GBS sepsis, but recommendations vary as to whether they should be offered following antenatal screening or based on risk factors alone. We aimed to determine the incidence of early-onset GBS sepsis in New Zealand five years after the publication of national risk-based GBS prevention guidelines.

Materials and methods: Prospective surveillance of early-onset GBS sepsis (defined as infection in the first 48 h of life) was undertaken between April 2009 and March 2011 through the auspices of the New Zealand Paediatric Surveillance Unit as part of a survey of infection presenting in the first week of life.

Results: There were 29 cases of confirmed early-onset GBS sepsis, including one case of meningitis, giving an incidence rate of 0.23 per 1000 (95% CI 0.16-0.33) live births. Three infants (10.3%) died. In 16 cases (55%), a maternal risk factor qualifying the mother for intrapartum antibiotics was present, but only five (31%) received this intervention. A retrospective review of the major hospital laboratory databases for this period identified two additional cases. A secondary sensitivity analysis taking account of these cases provided an estimated national incidence of 0.26 (95% CI 0.18-0.37) per 1000 live births.

Conclusions: Ten years after a similar survey and five years after promoting a single, risk-based prevention protocol nationally, the incidence of early-onset GBS disease in New Zealand has more than halved, but opportunities remain to further reduce the rate.

Keywords: Streptococcus agalactiae; newborn; prevention and control; sepsis; surveillance and monitoring.

Publication types

  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Female
  • Health Policy
  • Humans
  • Incidence
  • Infant, Newborn
  • Male
  • Medical Audit
  • New Zealand / epidemiology
  • Practice Guidelines as Topic
  • Prospective Studies
  • Public Health Surveillance
  • Retrospective Studies
  • Risk Factors
  • Sepsis / diagnosis
  • Sepsis / epidemiology*
  • Sepsis / etiology
  • Sepsis / prevention & control
  • Streptococcal Infections / diagnosis
  • Streptococcal Infections / epidemiology*
  • Streptococcal Infections / etiology
  • Streptococcal Infections / prevention & control
  • Streptococcus agalactiae*