Water, Sanitation and Cholera in sub-Saharan Africa

Improvements in water and sanitation should reduce cholera risk. But it is unclear which water and sanitation access are associated with cholera risk. We estimated the association between eight water and sanitation measures and annual cholera incidence access across sub-Saharan Africa (2010-2016) for data aggregated at the country and district-level. We fit random forest regression and classification models to understand how well these measures combined might be able to predict cholera incidence rates and identify high cholera incidence areas. Across spatial scales, piped or “other improved” water access was inversely associated with cholera incidence. Access to piped water, piped sanitation, and piped or “other improved” sanitation were associated with decreased district-level cholera incidence. The classification model had moderate skill in identifying high cholera incidence areas (cross-validated-AUC 0.81 95%CI 0.78–0.83) with high negative predictive values (92.5–100.0%) indicating the utility of water and sanitation measures for screening out areas that are unlikely to be cholera hotspots. While comprehensive cholera risk assessments must incorporate other data sources (e.g., historical incidence), our results suggest that water and sanitation measures could alone be useful in narrowing the geographic focus for detailed risk assessments. Synopsis We quantified the relationship between high-resolution estimates of water and sanitation access and cholera incidence and assessed the utility of water and sanitation measures in identifying high risk geographic areas in sub-Saharan Africa. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study did not receive any funding ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes All data produced are available online at https://www.healthdata.org/