Epidemiology of community-acquired bacterial meningitis

Purpose of review The epidemiology of bacterial meningitis has been dynamic in the past 30 years following introduction of conjugated vaccines against Haemophilus influenzae type B, Streptococcus pneumoniae and Neisseria meningitidis. The purpose of this review is to describe recent developments in bacterial meningitis epidemiology. Recent findings The incidence of bacterial meningitis in Western countries (Finland, Netherlands, and the United States) gradually declined by 3-4% per year to 0.7-0.9 per 100000 per year in the past 10-20 years. In African countries (Burkina Faso and Malawi), incidence rates are still substantially higher at 10-40 per 100000 persons per year. Introduction of pneumococcal conjugate vaccines have not consistently decreased overall pneumococcal meningitis incidence because of serotype replacement. Following the introduction of serogroup A and C meningococcal vaccines, the incidence of meningococcal meningitis because of these serogroups strongly decreased. Novel outbreaks in the African meningitis belt by serogroup C and increased incidence of serogroup W in the United Kingdom and the Netherlands were observed recently. Summary Bacterial meningitis remains an important infectious disease, despite a gradual decline in incidence after large-scale vaccination campaigns. Further development of vaccines with broader coverage is important, as is continuous surveillance of bacterial meningitis cases.