Following relaxed border controls, non-endemic Taiwan suffered a massive dengue outbreak in 2023, totaling 26,706 cases. Researchers analyzed national surveillance data, weather records, mosquito density (Breteau Index), and viral genomes to identify what drove the surge.

Key Findings * Dual Serotypes: DENV-1 and DENV-2 co-circulated, primarily hitting Tainan (80.7%) and Kaohsiung (11.9%).

• Global Origins: Genetic sequencing traced the viruses back to Southeast Asian strains, revealing new mutations compared to historical local outbreaks.
• City-Specific Drivers: In Kaohsiung, transmission was independently driven by temperature, rainfall, and mosquito levels. In Tainan, rainfall and a lag in imported cases were the primary drivers, while mosquito density mattered less.

The Takeaway The 2023 outbreak was caused by a mix of imported cases, weather changes, and mosquito dynamics. Controlling future outbreaks require targeted local vector control and climate-based early warning systems.

Read more: https://pmc.ncbi.nlm.nih.gov/articles/PMC12849096/

First Author: Jie-Yu Huang

Co-author: Arunee Thitithanyanont

Corresponding Author: Sheng-Fan Wang