Abstract
Vector-borne diseases (VBDs) remain a major public health burden, particularly in tropical and subtropical regions. Aedes aegypti mosquitoes are primary vectors of several VBDs, and understanding their population dynamics is critical for developing effective control strategies. This study investigates seasonal sex ratio variation in A. aegypti populations within urban environments of El Salvador's seasonally dry neotropical biomes. Using data from an ongoing surveillance program, we analyzed the temporal distribution of male and female mosquitoes across eight sampling events. Our results reveal significant deviations from the expected 1:1 sex ratio, with a pronounced female bias during the dry season and a shift toward parity in the wet season. These findings suggest that environmental and anthropogenic factors influence sex ratio dynamics, potentially affecting reproductive success and population persistence. The observed sex ratio distortion has important implications for vector ecology and biocontrol, emphasizing the need to incorporate seasonal and urban ecological variation into vector management strategies. Integrating these ecological insights into biocontrol programs could enhance the effectiveness of interventions aimed at reducing VBD transmission in seasonally dry tropical regions.