Trends in bacterial, mycobacterial, and fungal meningitis in England and Wales 2004-11: an observational study

Background Meningitis remains one of the most feared infectious diseases worldwide, yet there are few population-based studies on the epidemiology, causes, or trends over time in meningitis, especially in industrialised countries. Our aim was to do such a study using routinely reported data available in England and Wales. Methods In England and Wales, UK National Health Service hospitals routinely report laboratory-confirmed pathogens electronically to Public Health England. Records of all positive bacterial, mycobacterial, and fungal results from cerebrospinal fluid or from blood cultures in patients with clinical meningitis were extracted for analysis. The percentage change in annual incidence was estimated using linear regression analysis of the log of the annual incidence. Findings During 2004-11, 7061 cases of meningitis were reported (mean annual incidence 1.62 per 100 000 people, 95% CI 1.58-1 66), including 2594 cases in children (37%). The incidence of bacterial (1.44 per 100 000 people, 1.41-1.48), fungal (0.09, 0.08-0.10), and mycobacterial (0.09, 0.08-0.09) meningitis remained stable overall and across the age groups, apart from significant year-on-year increases in children younger than 3 months (978 cases; incidence 72.2 per 100 000 people; annual increase 7.4%, 5.1-9.8; p<0.0001) driven mainly by group B streptococci (GBS), and in adults aged 65 years or older (752 cases; incidence 1.2 per 100 000 people; annual increase 3.0%, 1.4-4.8; p<0.0001) primarily because of Escherichia coli. By contrast, meningococcal meningitis rates declined steadily, but remained the most common cause of meningitis in children. Overall, five groups of bacteria accounted for 60% (3790/6286) of bacterial meningitis cases: Neisseria meningitidis (1350 cases, 22%), Streptococcus pneumoniae (1143, 18%), Staphylococcus aureus (652, 10%), GBS (326, 5%), and E coli (319, 5%). Interpretation In England and Wales, laboratory-based surveillance shows a remarkably stable incidence of bacterial, fungal, and mycobacterial meningitis in recent years, although there were differences in individual trends among the main pathogens causing meningitis in different age groups.