Extreme Weather and Malaria Control (minimizing the impact of disruptions)

Climate change is making extreme weather more extreme, with consequences for infectious disease dynamics. We discuss our efforts to understand the impact of one category of extreme weather event, tropical cyclones, on efforts to control malaria. Data from Madagascar, a country subject to frequent cyclones, show disruptions to typical public health programs following such events can erode progress in reducing malaria. We argue that, in a future where climate-driven disruptions to intervention efforts are more common, disease control will benefit from deploying longer lasting prevention tools. Exploring malaria vaccination as an example, we estimate anticipatory deployment of (even modestly effective) vaccines would have approximately halved the number of symptomatic malaria cases following Tropical Cyclones Batsirai (2022) and Freddy (2023) in southeast Madagascar. While much of the discussion of climate change and malaria has focused on possible expansion of the disease into peripheral areas, our data show the need for investment in study and intervention in the high burden, core areas of malaria transmission.