Chilling Prospects Special Edition: Heat Vulnerability & Mortality

Heatwaves in Europe and North America make the global news. When the mercury climbs in the Sahel Region in Northern Africa, it more than often goes unnoticed. Temperatures that shock in a temperate continent are unremarkable in much of Sub-Saharan Africa, South Asia, and Latin America, where heat is not a seasonal event but a chronic condition, one that is getting worse, and where the deaths it causes go largely uncounted.

In Europe and parts of the Americas, people are beginning to understand the true scale of heat mortality – excess death studies, improving surveillance systems, and a growing body of epidemiological research are slowly making the burden visible. Across the Global South, that picture is almost entirely absent. Death registration systems are incomplete, epidemiological methods developed in temperate, high-income settings are not transferable to the emerging and developing country context, and the research base remains thin.

This Special Edition of Chilling Prospects examines what we do and do not know about heat-related mortality in Sub-Saharan Africa, South Asia, South East Asia, and Latin America and the Caribbean. It makes the case for why measurement of heat-related mortality matters, explains how it is currently attempted and where methods fall short, and presents the evidence for heat adaptation, cooling access and energy access as the most direct levers for reducing risk. It concludes with a shared agenda: for better evidence, stronger research collaboration, and heat action grounded in the realities of the communities most exposed.