Sex-Ratio Distortion of <em>Aedes aegypti </em>(L.) in El Salvador: Implications for Urban Ecology and Biocontrol in Seasonally Dry Neotropical Biomes

Abstract

Vector-borne disease (VBD) accounts for more than 17% of the global infectious disease burden, disproportionately affecting developing nations within tropical and subtropical areas. As Aedes aegypti mosquitoes are the principal vector for the transmission of many Public Health pathogens, our study examined their population dynamics within the seasonal context of tropical dry biomes in El Salvador as incidence of VBD in this region has increased in recent years. Species that rely on sexual reproduction must maintain a balanced sex ratio (1:1) to support their population dynamics, however, our phenological analysis of field-collected A. aegypti specimens revealed significant sex ratio variations during dry and wet seasons. Interestingly, we detected a seasonal shift that favored female mosquitoes during the dry season, highlighting the dynamic nature of mosquito populations in highly urbanized environments like El Salvador. By linking sex ratio distortions to anthropogenic factors, our study underscores the importance of comprehensively characterizing the urban ecology of vectors for the development of effective biocontrol strategies. As such, we advocate for more nuanced vector control approaches that consider ecological factors as well as the human behaviors that influence mosquito breeding habitats to effectively combat the rise of VBDs amid global climate changes.