Mosquitoes Evolving Resistance Against Dengue

As previously stated in my first post, there are currently no vaccines commercially available for Dengue Fever. So what is in the pipeline? 

Earlier this year a study was carried out on investigated the effects of the microsporoidan parasite Vavraia culicis on the female Aedes. aegypti mosquito. A series of experiments were created involving the female mosquito and its microsporoidian parasite to show how intra-specific competition and parasitism shape life history traits. Many of these life-history changes are thought to be down to reallocation or decrease in the host's resources either caused by the host to minimize the effects of infection or caused by the parasite to maximize its growth rate. Parasitic infection is often associated with changes in host life-history traits, such as host development.

http://onlinelibrary.wiley.com/doi/10.1111/eva.12144/full

Results showed Vavraia. culicis caused changes in the behaviour of the female Aedes. aegypti this is seen in the graphs above.Infected female mosquitoes were found to be less likely to take a blood meal in the first few days after Vavraia. culicis infection (shown in graph A). Females that did feed took smaller volumes of blood than uninfected females (Shown in graph B). Infected females were noted to produce 20% fewer eggs than uninfected female mosquitoes (Shown in graph C). It was also suggested the female mosquitoes could alter their life-history traits to bring forward their schedule of reproduction and The survival rates of the adult mosquitoes were reduced if infected with Vavraia. culicis.

Could this information be the breakthrough we have been looking for? Is this a possible future management strategy?

Sy, V. E., Agnew, P., Sidobre, C., & Michalakis, Y. (2014). Reduced survival and reproductive success generates selection pressure for the dengue mosquito Aedes aegypti to evolve resistance against infection by the microsporidian parasite Vavraia culicis. Evolutionary Applications.