Effects of Wolbachia and dengue virus infection on the mosquito Aedes aegypti

Dengue fever and the associated dengue hemorrhagic fever cause large amounts of morbidity and mortality throughout the world.  The lack of an effective vaccine or treatment leaves vector control as the primary intervention strategy to limit the impact of these diseases.  Intracellular bacteria of the genus Wolbachia have been suggested as both a gene drive mechanism and a population suppressant; however, the interactions between the dengue virus, Wolbachia, and mosquitoes have not been investigated in depth.  Therefore, we compared Wolbachia infected and uninfected Aedes aegypti mosquitoes after feeding on dengue infected or uninfected blood to see how infection by the bacteria, the virus, or both affects the overall fitness of the mosquito host.  By measuring the lifespan, fecundity, and development time of co- and singly infected Aedes aegypti mosquitoes, we were able to compare the statistics to those of uninfected mosquitoes and observe the effects of infection.  It is important to take these effects into account when considering using Wolbachia to control major disease vectors, as interactions among the mosquito’s microbial flora can greatly affect the efficiency of the intervention strategy.