D3019: Effect of temperature on Wolbachia during Culex pipiens development

During the outbreak of West Nile Virus (WNV) in the United States in 2003, Cx. pipiens were estimated to contribute to approximately 80% of human cases. This could be related to the ubiquitous presence of the mosquito, its feeding on birds which are reservoirs of the virus, its high local abundance, and its close association with domestic environment. Cx. pipiens is one of the main WNV vectors in North America and Cx. pipiens is well known for its natural infection with Wolbachia. When mating occurs between insects of the same species with different Wolbachia infection status, Cytoplasmic incompatibility (CI) and embryonic mortality can result. Temperature can influence the mosquito life cycle development, and Wolbachia replication and density in its host is also sensitive to temperature. This research aims to determine the effect of temperature on Wolbachia presence and Cx. pipiens development. DNA molecular analysis and microscopy techniques (FISH) will be used for Wolbachia detection and relative quantification in embryo tissues from Cx. pipiens reared at three different room temperatures. Preliminary outcomes will include image analysis of Wolbachia location and differences in its relative abundance when the mosquito eggs are submitted to temperature treatments throughout development. At higher temperatures, Wolbachia abundance is likely to be reduced which could mean greater susceptibility to WNV in the subsequent generation of Cx. pipiens.