Shifting Dynamics of Dengue Virus Serotype 2 and Emergence of Cosmopolitan Genotype, Costa Rica, 2024.

Dengue remains a major public health challenge. In Costa Rica, we implemented nationwide genomic surveillance to track dengue virus serotype 2 cosmopolitan genotype emergence. Phylogenetic and eco-epidemiologic analyses revealed early detection, climate-driven spread, and spatial heterogeneity. Our findings underscore the need for integrated surveillance to guide adaptive responses to emerging arboviral threats.