The New England Journal of Medicine, 22 April 2025

Climate Change and Human Health — A Research Agenda for Action

The health effects of climate change are profound and multifaceted. Extreme weather events such as heat waves, hurricanes, wildfires, and floods cause injury, death, and a growing burden of mental health conditions. Shifting environmental conditions drive the spread of vectorborne diseases, worsen air quality, and threaten food and water security, while disrupting sanitation systems and exacerbating malnutrition. These effects ripple across communities, disproportionately burdening high-risk populations, straining public health systems, and deepening existing inequities. They are further shaped by social determinants, including economic status, access to health care, and preexisting conditions.

A growing body of research has documented these effects, with successive reports from the Intergovernmental Panel on Climate Change and the World Health Organization underscoring the urgency of addressing climate-related health threats. However, substantial knowledge gaps remain. Research on climate-related health effects is disproportionately concentrated in high-income countries, which leaves substantial uncertainty about effects in low- and middle-income countries, where climate vulnerabilities are often greatest.