Interacting climatic, environmental, biologic and socio-economic drivers of the global dengue expansion

Dengue is the most rapidly expanding mosquito-borne viral disease worldwide. The worst year on record was 2024, with over 100 countries reporting 14.4 million cases and over 11,000 deaths. Since then, and up to August 2026, another 7.4 million cases and over 5000 deaths have been reported. The region of the Americas was impacted the most, followed by South-East Asia and the Western Pacific. Both the spread of dengue viruses (DENV) and their primary vectors, Aedes aegypti and Aedes albopictus, are driven by several factors. Globalization has accelerated vector dispersal, particularly through international trade and transportation networks. The movement of desiccation-resistant eggs in used-vehicle tyres and the inadvertent transport of adult mosquitoes via trucks and passenger vehicles have enabled the establishment of vector populations in previously uncolonized regions. Human mobility and unplanned urbanization further contribute to dengue emergence by introducing DENV into susceptible populations where competent vectors circulate. Climate change has enhanced dengue transmission potential by altering temperature and rainfall patterns that influence mosquito survival, reproduction, biting behaviour and viral replication. Containing or even reversing this global dengue expansion will require a complementary set of interventions that rely on proven and novel control strategies, including sterile insect techniques, Wolbachia-infected mosquitoes, virus-resistant mosquito strains through CRISPR-Cas9 gene drive, vaccines, antiviral drug prophylaxis and urban interventions that eliminate Aedes habitats. Building climate-resilient urban environments through sustainable development to minimize the urban heat island effect and advancing climate-informed early warning systems are long-term strategies for effective dengue control.