Abstract
Bacterial meningitis remains an international public health problem with a major burden in Africa. They are mainly due to three bacteria: Neisseria meningitidis (Nm), Streptococcus pneunomiae (Sp) and Haemophilus influenzae type b (Hib), the human rhino-pharynx being the ecological niche of bacteria. The transmission is aerial, direct, interhuman or by contact with the respiratory secretions of the patient or the healthy carrier. While the meningitis belt stretching from Senegal to Ethiopia is widely studied, the ecology of meningitis outside this particular area is still poorly understood. The aim of this thesis is to explore the ecology of bacterial meningitis in the Democratic Republic of Congo (DRC) based on epidemiological, genetic and socio-environmental data for the period 2000-2018. Despite the low rate of biological confirmation of cases (14%), we identified risk health zones, grouped into 8 spatial clusters. These clusters allowed us to highlight a seasonality of bacterial meningitis that is not very marked and which is variable from one region to another in the DRC, in contrast with the strong seasonality described in the meningitis belt. Urbanized areas where populations show a low economic index of well-being, high latitude and longitude, medium to low altitude, with savannah vegetation, with medium temperatures, are significant risk factors, alone or in synergy, to explain meningitis cases in the DRC. The distribution of aerosols and dust on the Congolese territory occurs about two to three weeks before the epidemic outbreaks of bacterial meningitis for two categories of monthly groupings (December to February and May to September). These results foreshadow the possibility of developing an early warning system. Finally, we propose an explanatory conceptual model of meningitis in the DRC whose rate of occurrence of the first cases is well regulated by the movement of dust and aerosols over the country.The recognition of bacterial meningitis as an international priority, particularly outside the belt, whose characteristics are yet to be better understood, could contribute to the achievement of the objectives of sustainable development, and more particularly those related to SDG 3 "health and well -being for everyone ".