Antenatal screening and intrapartum management of Group B streptococcus in the UK



The recent publication by Kenyon et al.1 highlights the dilemma faced by many clinicians in choosing the best management strategy for the prevention of Early Onset Group B Streptococcal Disease of the Newborn (EOGBSD). Although the Centres for Disease Control and Prevention Atlanta, GA (CDC) has recently published new recommendations for using a screening strategy for the prevention of EOGBSD,2 high level evidence is still lacking that screening is indeed superior to a risk factor-based strategy. For that reason, Australia does not have a national antenatal screening policy. Practice varies from state to state and, in some states, from clinician to clinician. The Australasian Society for Infectious Diseases presents both risk factor and antenatal screening algorithms without recommending one over the other while the Royal Australian and New Zealand College of Obstetricians and Gynaecologists (ANZCOG) highlights the CDC recommendations without endorsing them outright.

A recent article by Gilbert emphasises that while neither strategy prevents all cases, either, if properly implemented, can reduce the incidence of EOGBSD.3 Kenyon underscores that several factors involved, including the rate of EOGBSD, the probable reduction achievable, the costs of education and implementation of the new strategy and the burden of disease on society must be assessed to adequately decide if change in practice is warranted and achievable.

Kenyon's survey also highlights the dangers in implementing a change in policy without adequate training and education of clinical and laboratory personnel. In her study, of the 2% of maternity units who performed routine antenatal swabs for GBS in 2001, none took cultures as advocated by the CDC. A recent unpublished survey in Queensland, Australia showed similar findings where a significant proportion of clinicians who said they were screening antenatally were unable to identify the correct gestation for screening or the correct culture site and technique.

In Australia, a GBS Collaborative Group is proposing to conduct a retrospective clinical audit of EOGBSD cases in two states, that together account for around 40% of Australian births. This will assess compliance with existing prevention strategies and will also enable prospective surveillance to be conducted.

We agree that a large multicentre RCT is the only way to resolve this dilemma and given the diversity of approaches to this disease in Australia, many maternity centres should be in a position to participate in such a trial.