Fitness consequences of oviposition behaviour in Aedes aegypti

Aedes aegypti is the main vector of Dengue fever, the most important mosquito-borne viral disease affecting humans. Oviposition site selection has direct effects on vector fitness and population numbers. Female Ae. aegypti that emerged from poor habitats with high larval densities and low food availability were smaller, had lower teneral reserves, and laid smaller, fewer, and less viable eggs than did females raised in good habitats. Females that were raised under good conditions but were infected with a trematode parasite were smaller, laid smaller eggs, and fewer parasitized females oviposited than control females. Females should evaluate site quality and avoid ovipositing in poor habitats. We have identified putative oviposition deterrent compounds, possibly of larval origin, in waters containing parasitized or stressed larvae. Females that recognize these compounds may reject these oviposition sites and search for sites that will allow them to maximize their individual fitness.