Toward a geography of community health workers in Niger: a geospatial analysis

Background Little is known about the geography of community health workers (CHWs), their contribution to geographical accessibility of primary health care (PHC) services, and strategies for optimizing efficiency of CHW deployment in the context of universal health coverage (UHC). Methods Using a complete georeferenced census of front-line health facilities and CHWs in Niger and other high resolution spatial datasets, we modelled travel times to front-line health facilities and CHWs between 2000-2013, accounting for training, essential commodities, and maximum population capacity. We estimated additional CHWs needed to maximize geographical accessibility of the population beyond the reach of existing front-line health facilities and CHWs. We assessed the efficiency of geographical targeting of the existing CHW network compared to modelled CHW networks designed to optimize geographical targeting of the estimated population, under-five deaths, and plasmodium falciparum malaria cases. Results The percent of the population within 60 minutes walking to the nearest CHW increased from 0·0% to 17·5% between 2000-2013, with 15·5% within 60 minutes walking to the nearest CHW trained on integrated community case management (iCCM) — making PHC services and iCCM, specifically, geographically accessible for an estimated 2·3 million and 2·0 million additional people, respectively. An estimated 10·4 million people (59·0%) remained beyond a 60-minute catchment of front-line health facilities and CHWs. Optimal deployment of 8064 additional CHWs could increase geographic coverage of the estimated total population from 41·5% to 73·6%. Geographical targeting of the existing CHW network was inefficient but optimized CHW networks could improve efficiency by 55·0%-81·9%, depending on targeting metric. Interpretations We provide the first high-resolution maps and estimates of geographical accessibility to CHWs at national scale, highlighting improvements between 2000-2013 in Niger, geographies where gaps remained, approaches for improving targeting, and the importance of putting CHWs on the map to inform planning in the context of UHC.