El Niño and the shifting geography of cholera in Africa

Significance In the wake of the 2015–2016 El Niño, multiple cholera epidemics occurred in East Africa, including the largest outbreak since the 1997–1998 El Niño in Tanzania, suggesting a link between El Niño and cholera in Africa. However, little evidence exists for this link. Using high-resolution mapping techniques, we found the cholera burden shifts to East Africa during and following El Niño events. Throughout Africa, cholera incidence increased three-fold in El Niño-sensitive regions, and 177 million people experienced an increase in cholera incidence. Without treatment, the case fatality rate can reach 50%, but accessible, appropriate care nearly eliminates mortality. Climatic forecasts predicting El Niño events 6–12 mo in advance could trigger public health preparations and save lives.