Group B Streptococcal disease in England (1998 - 2017): a population based observational study.

BACKGROUND AND OBJECTIVES Group B Streptococcus (GBS) is the leading cause of sepsis and meningitis in infants <90 days. In this study, the burden of GBS disease and mortality in young infants in England was assessed. METHODS Using linked hospitalisation records from every National Health Service (NHS) hospital from 1 April 1998 to 31 March 2017, we calculated annual GBS incidence in infants aged <90 days and, using regression models, compared their perinatal factors, rates of hospital-recorded disease outcomes and all-cause infant mortality rates with those of the general infant population. RESULTS 15,429 infants aged <90 days had a hospital-recorded diagnosis of GBS, giving an average annual incidence of 1.28 per 1000 live births (95% CI 1.26-1.30) with no significant trend over time. GBS-attributable mortality declined significantly from 0.044 (95%CI 0.029-0.065) per 1000 live births in 2001 to 0.014 (95%CI 0.010-0.026) in 2017 (annual percentage change -6.6, 95%CI -9.1 to -4.0). Infants with GBS had higher relative rates of visual impairment (HR 7.0 95% CI 4.1-12.1), cerebral palsy (HR 9.3 95% CI 6.6-13.3), hydrocephalus (HR 17.3 95% CI 13.8-21.6) and NEC (HR 18.8 95% CI 16.7-21.2) compared with those without GBS. CONCLUSIONS Annual rates of GBS disease in infants have not changed over 19 years. The reduction in mortality is likely multifactorial and due to widespread implementation of antibiotics in at-risk mothers and babies as well as advances in managing acutely unwell infants. New methods for prevention, such as maternal vaccination, must be prioritised.