Group B streptococcal disease 1
At the time of surveillance, Group B Streptococcal disease was the most common cause of severe, early-onset neonatal disease (EOGBSD) and an important cause of late-onset neonatal disease. Administering antibiotics could prevent EOGBSD. There was concern that there were no national policies for use in the UK/ROI. These policies needed to be evidence-based, and there was no data on the incidence and risk factors for disease in UK/ROI infants. The aim of this project is to describe the burden of invasive GBS disease in infants <90 days of age in the UK and ROI.
Lead investigator
Dr P Heath
About the study
At the time of this study, Group B Streptococcal (GBS) Disease was the most common cause of severe early-onset neonatal infection in developed countries. However, in the UK and ROI, the incidence and risk factors for group B streptococcal disease, whether early onset (< 7 days) (EOGBSD) or late onset (7 – 90 days) (LOGBSD), were not well studied.
A passive surveillance study of 25 British centres in the late 1970s estimated an incidence of 0.3/1000 live births (< 2 months of age). There have been four published studies from England from the 1980s and 1990s which estimated incidence rates of between 0.6-1.2 / 1000 (average 0.7). A retrospective series from the Northern Region calculated a mortality from EOGBSD of 0.08 / 1000 live births. A major weakness of these studies is that they have rarely included major urban and deprived areas. By comparison, the incidence rate of EOGBSD in the USA was approximately 1.4/1000.
EOGBSD could be prevented through intra-partum or post-partum antibiotic prophylaxis. Various prevention strategies were proposed; these generally relied on mass screening of pregnant women for carriage of GBS and/or identifying women with specific risk factors for disease. Which strategy should have been applied to the UK/ROI depended on the incidence of EOGBSD and on its risk factors. It was conceivable that the burden of disease in the UK/ROI may have been so low that a no-intervention strategy would have been the most cost-effective.
The risk factors on which interventions were based were derived mostly from data from the USA. These included maternal age (under age 20), black ethnic group, prolonged rupture of membranes, prematurity and low birth weight. Such factors may not have necessarily applied outside the USA. In addition to cost, increased exposure to antibiotics had other possible implications, such as anaphylaxis, as well as encouraging antibiotic resistance and the emergence of other pathogens.
Several ad hoc prevention policies were applied in UK settings, some based on local, smaller surveillance studies and others based on experience from elsewhere, especially the USA. In most places, policies were yet to be devised, though increasingly centres were feeling the need to do so. There was therefore an increasing need for national guidelines. The Public Health Laboratory Service prioritised the gathering of national data. Only with a national study would data be generated of sufficient size to make robust recommendations about policies and practices.
Objectives:
- Estimate the incidence of invasive GBS disease in British and Irish infants aged < 90 days
- Find data on the clinical presentation of cases of invasive GBS disease
- Find the mortality and short-term complication rate of GBS disease
Duration
March 2000 – March 2001
Published papers
Heath PT, Balfour G, Weisner AM, Efstratiou A, Lamagni TL, Tighe H, O’Connell LA, Cafferkey M, Verlander NQ, Nicoll A, McCartney AC; PHLS Group B Streptococcus Working Group. Group B streptococcal disease in UK and Irish infants younger than 90 days. Lancet. 2004 Jan 24;363(9405):292-4. doi: 10.1016/S0140-6736(03)15389-5. PMID: 14751704.
BPSU 15th Annual report 2000-2001
Support Group
Group B Strep Support
Web: www.gbss.org.uk Email: info@gbss.org.uk