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


METHODS
The literature was searched to provide a multi-disciplinary overview of the determinants of meningitis transmission dynamics in the African meningitis belt.


RESULTS
Seasonal 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.


CONCLUSIONS
Efforts 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.
Combining Health Information, Computation and Statistics, Lancaster Medical School, Lancaster University, Lancaster, UK. Electronic address: lydiane.agier@univ-grenoble-alpes.fr.
Lydiane
L
Agier
Centre de Recherches de Climatologie (CRC), UMR 6282 CNRS Biogeosciences, Université de Bourgogne, Dijon, France.
Nadège
N
Martiny
Institut de Recherche pour le Développement, UMR INTERTRYP IRD-CIRAD, Antenne IRD Bobo Dioulasso, Bobo, Burkina Faso.
Oumy
O
Thiongane
EHESP French School of Public Health, Sorbonne Paris Cité, Rennes, France; Unité de l'Epidémiologie des Maladies Emergentes, Institut Pasteur, Paris, France.
Judith E
JE
Mueller
Unité de l'Epidémiologie des Maladies Emergentes, Institut Pasteur, Paris, France; Department of Ecology and Evolutionary Biology, Princeton Environmental Institute, Princeton University, Princeton, New Jersey, USA.
Juliette
J
Paireau
Department of Zoology, Oxford University, Oxford, UK.
Eleanor R
ER
Watkins
School of Social and Community Medicine, University of Bristol, Bristol, UK.
Tom J
TJ
Irving
EHESP French School of Public Health, Sorbonne Paris Cité, Rennes, France; Unité de l'Epidémiologie des Maladies Emergentes, Institut Pasteur, Paris, France.
Thibaut
T
Koutangni
MIVEGEC, UMR 590CNRS/224IRD/UM, Montpellier, France; Service de Parasitologie-Mycologie, Faculté de Médecine, Université Cheikh Anta Diop, Fann, Dakar, Senegal.
Hélène
H
Broutin
D000349:Africa / Q000453:epidemiology; D000818:Animals; D006801:Humans; D008585:Meningitis, Meningococcal / Q000453:epidemiology* / Q000382:microbiology; D009345:Neisseria meningitidis / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology; D016036:Seroepidemiologic Studies
African belt; Bacterial meningitis; Disease control; Research priorities