Title : Preventing Early Onset Group B Streptococcus (EOGBS): A narrative review of bacteriological screening practices in the UK
Abstract:
Introduction: 20-40% of UK adults carry Group B streptococcus (GBS) in their intestines, urinary tract or genital tract. Vertical transmission of GBS to neonates during birth is the leading cause of neonatal sepsis in the UK and can also result in neurodevelopmental delays, meningitis and death. The UK currently does not conduct routine GBS screening, instead using a risk-based approach to determine if intrapartum antibiotic prophylaxis is necessary, in line with the 2017 Royal College of Obstetricians and Gynaecologists (RCOG) guideline. However, many other countries take a more rigorous approach, using universal screening, as recommended by the 2024 World Health Organisation (WHO) guideline.
Objectives: To review the current literature on GBS screening strategies to determine whether a risk-based approach or universal screening is superior in preventing early-onset neonatal GBS disease (EOGBSD) and its complications.
Methods: To conduct this narrative review, a literature search was implemented according to PIRO (Population, Index test, Reference standard, Outcome), a modified PICO approach, alongside pre-defined inclusion criteria. Two independent reviewers used the Appraisal of Guidelines for Research and Evaluation (AGREE II) tool to appraise the selected RCOG and WHO guidelines. There was also a dual independent appraisal of three systematic reviews and two primary studies using the Critical Appraisal Skills Programme (CASP) checklist.
Results: The UK National Screening Committee’s systematic review, which the RCOG guideline is based on, favoured a risk-based approach. However, it was a rapid-review which only contained three studies and had significant methodological limitations. Comparatively, Panneflek et al.’s systematic review, a key piece of evidence for the WHO guideline, favoured universal screening. It consisted of 72 studies and was methodologically stronger. Other related factors were considered: a cost-effectiveness systematic review, as well as primary studies on clinical effectiveness and acceptability were also found to favour universal screening. There are no high-quality randomised control trials (RCTs) published to date, however a cluster RCT (GBS3) is currently being undertaken in the UK.
Conclusions: This review found evidence to suggest that universal GBS screening is more effective than a risk-based approach in preventing EOGBSD and would therefore support a change to the UK’s current screening strategy. However, the ongoing GBS3 trial will be essential for reviewing the RCOG guideline, and its results should allow for more definitive conclusions.
