Evidence-Based WASHmobile Anticipatory Action Framework to Reduce Cholera Outbreaks during Extreme Weather Events in the Democratic Republic of the Congo

Extreme weather contributes to cholera outbreaks globally. We examined associations between extreme weather and cholera through 4 years of surveillance at 115 healthcare facilities in the Democratic Republic of the Congo, and built an anticipatory action framework through WASHmobile for water, sanitation, and hygiene mobile messaging during extreme weather. Drought and wet conditions were defined using 3-month Standardized Precipitation Indices with CHIRPS data. A test-negative design assessed associations between extreme weather and culture-confirmed Vibrio cholerae among 1,068 diarrhea patients. Odds of cholera were higher during drought (OR: 1.94, 95% CI: 1.17-3.20) and extreme wet conditions (OR: 2.22, 95% CI: 1.39-3.55). During drought conditions in our randomized controlled trial of 2334 participants, handwashing with soap significantly declined in the standard arm but not the WASHmobile arm. Findings informed an anticipatory action framework where pre-defined climate triggers activate WASHmobile as an early warning system to reduce cholera outbreaks during extreme weather.