Bottom-up Regulation and Competition of Aedes Aegypti Along an Urban Gradient in Puerto Rico: Effects on Population Performance and Dengue Vector Competence

Aedes aegypti is the primary vector of globally important diseases including yellow fever, dengue, Zika, and chikungunya. The species population dynamics are related to urbanization as larvae mostly develop in human-made containers. I evaluated the connection between the urban landscape, containers, Ae. aegypti, and its competitor Ae. mediovittatus, in the San Juan Metropolitan Area, Puerto Rico. Performing laboratory experiments, I found a connected urban landscape-larval container system, in which the surrounding landscape influences detritus and nutrients within containers and where smaller and less nitrogen enriched Ae. aegypti are being produced in areas of higher impervious cover. I found that urban related changes in container detritus and larval density affect the life history traits (development time and biomass), nutrients, and isotopes of larval and adult female Ae. aegypti. I also found that urban related detritus and density changes influence female Ae. aegypti fecundity and transgenerational effects e.g., the life history traits (survival, development time, biomass) of the progeny (F2), and the population growth of the subsequent generation (F3). Lastly, I evaluated how urban related detritus and density changes influence female Ae. aegypti life history traits (survival, development time, and wing length), nutrient stoichiometry, and vector competence of dengue virus 1 (infection, dissemination, and transmission). I found that when nutrients are limited, Ae. aegypti females under lower larval competition, have lower competence for dengue virus 1. Also, the combination of high interspecific competition with Ae. mediovittatus and high detritus biomass decreased Ae. aegypti survival and increased dengue virus 1 dissemination rates. Understanding the ecology of this mosquito species and its influence on vector competence within the context of urbanization, has relevant implications for Ae. aegypti driven dengue virus 1 disease dynamics in urban and suburban areas where detritus inputs differ among mosquito container habitats.