Impact evaluation of water supply improvements in Uvira, DRC

The cholera burden is concentrated in endemic settings with inadequate water, sanitation and hygiene access. There is limited rigorous evidence for the impact of improved water supply on endemic cholera transmission in low-income urban settings. We propose a pragmatic health impact evaluation of a large-scale water supply intervention in Uvira (South Kivu, Democratic Republic of the Congo), a cholera transmission hotspot. A stepped-wedge cluster randomised trial (SW-CRT) was designed to evaluate the impact of a large-scale drinking water supply intervention on cholera incidence among the 280,000 inhabitants of Uvira. The city was divided into 16 clusters, where new community and household taps will be installed following a randomised sequence over a transition period of up to 8 weeks in each cluster. The primary trial outcomes are the monthly incidence of “confirmed” cholera cases (patients testing positive by rapid detection kit) and of “suspected” cholera cases (patients admitted to the cholera treatment centre). Concurrent process and economic evaluations will provide further information on the context, costs and efficiency of the intervention. Overall, this research has the potential to provide robust evidence to support more effective cholera prevention in challenging, high-burden settings. This trial is registered on clinicaltrials.gov (NCT02928341).

The Uvira research provides a unique opportunity to inform future investments in water supply infrastructure improvements and cholera prevention strategies in endemic transmission hotspots.