Assessment of Global Dengue Transmission Risk Under Future Climate Scenarios

Abstract

Dengue is a climate-sensitive mosquito-borne infectious disease with a rapidly increasing incidence and global transmission. Climate change alters the suitability of mosquito vectors, affecting viral transmission. We assessed the global dengue transmission potential and suitable months under future climate scenarios by integrating the mosquito-borne virus suitability index (Index P) with temperature and humidity projections from 12 global climate models. A substantial expansion of dengue risk zones from tropical to temperate regions was projected. The magnitude and pace of dengue risk escalation in China and the U.S. far exceed other temperate regions, with a considerable increase in at-risk population and exposed land areas. In contrast, Europe exhibits a more delayed and moderate increase in dengue risk. In the SSP245 scenario for the 2050s, high dengue suitability zones are prominently located in Latin America, Southeast Asia, and sub-Saharan Africa with emergent areas in southern North America and East Africa. By 2100, these zones expand to southern China and northern Australia. Under the SSP585 high-emission scenario, the global dengue risk landscape shifts dramatically, with extensive risk zones emerging in the southeastern United States, China, and southern Europe, while some tropical regions such as Brazil and India experience a notable decline in transmission suitability due to extreme heat stress. By extending Index P to long-term projections, this study uncovers both underappreciated early surges in temperate regions and unexpected declines in overheated tropics. These insights are critical for improving early warning systems in newly exposed populations.