Towards understanding the epidemiology of Neisseria meningitidis in the African meningitis belt: a multi-disciplinary overview

- A better understanding of the determinants of bacterial meningitis dynamics is crucial.
- Improved surveillance and the implementation of large-scale longitudinal studies are needed.
- Improving markers of protection and comparing molecular characteristics of clones is needed.
- Integrating climate and social factors into control strategies is a priority.
- Investigating the disease dynamics on a smaller spatial scale would be beneficial.

SummaryObjectivesNeisseria meningitidis is the major cause of seasonal meningitis epidemics in the African meningitis belt. In the changing context of a reduction in incidence of serogroup A and an increase in incidence of serogroups W and C and of Streptococcus pneumoniae, a better understanding of the determinants driving the disease transmission dynamics remains crucial to improving bacterial meningitis control.MethodsThe literature was searched to provide a multi-disciplinary overview of the determinants of meningitis transmission dynamics in the African meningitis belt.ResultsSeasonal hyperendemicity is likely predominantly caused by increased invasion rates, sporadic localized epidemics by increased transmission rates, and larger pluri-annual epidemic waves by changing population immunity. Carriage likely involves competition for colonization and cross-immunity. The duration of immunity likely depends on the acquisition type. Major risk factors include dust and low humidity, and presumably human contact rates and co-infections; social studies highlighted environmental and dietary factors, with supernatural explanations.ConclusionsEfforts should focus on implementing multi-country, longitudinal seroprevalence and epidemiological studies, validating immune markers of protection, and improving surveillance, including more systematic molecular characterizations of the bacteria. Integrating climate and social factors into disease control strategies represents a high priority for optimizing the public health response and anticipating the geographic evolution of the African meningitis belt.