D3022: Prevalence and diversity of Wolbachia infections in Florida mosquitoes

Mosquito-transmitted diseases, such as malaria, dengue fever, and mosquito-borne encephalitis, are significant threats to global public health, causing millions of deaths annually. Scientists have been developing novel approaches for mosquito control. Wolbachia, a bacterial endosymbiont naturally found in many arthropod species, is an essential part of several of these mosquito control strategies because it can suppress mosquito populations and block infection with important pathogens like dengue virus. Critically, we know very little about which mosquito species naturally harbor Wolbachia infection and how prevalent such infections are in mosquito populations. This is important because host-pathogen interactions in mosquitoes that naturally harbor Wolbachia can vary greatly between mosquito species and populations, with potential consequences for the transmission of key pathogens. For instance, some native Wolbachia infections decrease mosquito susceptibility to arbovirus infection and reduce the rate of transmission, while others have no effects. For this reason, we characterized the Wolbachia infection status of diverse mosquito species from Florida. We collected mosquitoes from a local conservation area in Florida, Oslo Riverfront Conservation Area (ORCA), which is estimated to harbor 30 of 90 mosquito species found across Florida, including key vectors of medical and veterinary diseases. We used qPCR to assess Wolbachia infection frequencies and Wolbachia titers then sequenced key Wolbachia genes to assess the genetic divergence of Wolbachia strains found in mosquitoes. Our results will facilitate the characterization of the role that native Wolbachia strains play in modulating pathogen infection and transmission by mosquitoes in nature.