New title: Re-evaluating environmental associations with meningitis risk across Africa

Area of Science:

• Epidemiology
• Environmental Health
• Climate Science

Background:

• Meningitis epidemic distribution analysis in Africa is over two decades old.
• Climate change is an ongoing factor influencing disease patterns.
• Updating the analysis of the meningitis belt and its environmental risk factors is crucial.

Purpose of the Study:

• To update the geographical distribution of meningitis epidemics in Africa.
• To identify changes in the meningitis belt and associated environmental risk factors over the last two decades.
• To assess the impact of climate and land-cover variables on meningitis outbreaks.

Main Methods:

• Utilized bacterial meningitis epidemic data from the World Health Organization African Regional Office (WHO-AFRO) for 2003-2022.
• Processed monthly climate data (windspeed, rainfall, dust, humidity) into profiles using k-means clustering.
• Employed logistic regression, analyzing the association between environmental factors and meningitis epidemic history, with a sensitivity analysis excluding the Democratic Republic of Congo (DRC).

Main Results:

• Rainfall, dust, windspeed, and humidity showed the strongest statistical association with meningitis outbreaks.
• The model achieved 82.07% specificity and 82.22% sensitivity in identifying epidemic districts.
• The Sahelian region remains at highest risk, but the inclusion of the DRC suggested potential risk expansion to surrounding countries, which was not observed when the DRC was excluded.

Conclusions:

• The apparent extension of meningitis risk beyond the traditional belt may be due to surveillance limitations, not necessarily altered disease ecology.
• Laboratory confirmation of suspected meningitis cases and outbreaks is vital for accurate surveillance.
• Emphasizes the need for robust diagnostic confirmation to differentiate between true ecological shifts and data artifacts.