Dengue on the Move: Projected 77 Million Cases and Global Expansion into New Frontiers

Dengue fever, carried by Aedes mosquitoes, already sickens tens of millions each year, mainly in tropical and subtropical regions but climate change is reshaping this landscape. Using advanced computer models, our CCEH research team shows that rising temperatures and population growth will allow dengue-carrying mosquitoes to thrive in new regions—including higher latitudes such as North America and Europe, where dengue has not historically been a major concern.

This expansion of risk means global infections could climb by more than 50% by mid-century, reaching nearly 77 million cases annually.

Policy implications should focus on:

• Rising vulnerability: Newly exposed regions may face higher risk due to lack of immunity and limited epidemic response experience.
• Healthcare strain: In endemic areas, dengue already accounts for 10–20% of fever admissions—further increases could overwhelm systems.
• Mosquito dynamics: Ae. aegypti will expand with warming and drive future epidemics, while Ae. albopictus contracts.
• Action needed: Prioritize Ae. aegypti control through surveillance, vector reduction, and community engagement.

Dengue is no longer just a tropical disease. Climate change is transforming it into a global health challenge—demanding proactive policies, preparedness, and robust mosquito control efforts across both endemic hotspots and newly at-risk regions.

These findings come from our recent study published article:   Hu J., Horton B.P., Yeo T.W., Sung J.J.Y., Yim S.H.L. (2025). Mosquito and global dengue cases in a warming world. BMJ Public Health, 10 (5), e014688.