Dense residential areas promote gene flow in dengue vector mosquito Aedes albopictus

Aedes albopictus is a successful disease vector due to its ability to survive in a wide range of habitats. Despite its ubiquity and impact on public health, little is known about its differential gene flow capabilities across different city habitats. We obtained a comprehensive dataset of >27,000 genome-wide DNA markers across 105 wild-caught Ae. albopictus individuals from Singapore, a dengue-endemic tropical city with heterogeneous landscapes from densely populated urban areas to forests. Despite Singapore's challenging small-scale heterogeneity, our landscape-genomic approach indicated that dense urban areas are characterized by higher Aedes gene flow rates than managed parks and forests. We documented the incidence of Wolbachia infections of Ae. albopictus involving two strains (wAlbA and wAlbB). Our results dispel the misconception that substantial dispersal of Ae. albopictus is limited to urban greenery, with wide implications for vector management and critical insights into urban planning strategies to combat dengue transmission.