Culicids on the move: a genetic characterization of two mosquito disease vector species in eastern insular Newfoundland

Abstract

Mosquitoes (Diptera: Culicidae) are some of the most significant carriers of human and animal disease causing pathogens on our planet. However in regions where the prevalence of nuisance mosquitoes or diagnosed mosquito-borne illness is low, the motivation for efforts to monitor mosquito populations is often lacking, even though less well-known viral agents, capable of causing significant human or animal diseases, may be active. Recently, populations of two container breeding disease carrying mosquito species have been reported in St. John’s, the capital city of the Atlantic Canadian province of Newfoundland and Labrador. The first, Culex pipiens, is the primary vector of West Nile virus along the northeast seaboard of North America, while the second, Aedes japonicus, is a highly invasive mosquito species reported to play a role in the transmission of West Nile and La Crosse viruses. Here I report the results of two genetic analyses focused on investigating taxonomic identity, genetic diversity, and connectivity of these populations of medically important species. The first chapter utilizes a set of rapid molecular assays to describe the composition of two populations of Cx. pipiens on the Island of Newfoundland; that is, populations on the Island are a mix of the behavioural/physiological forms of Cx. pipiens. The second chapter uses population genetic techniques to describe the genetic characteristics of a population of Ae. japonicus in Newfoundland, as well as how this population may or may not be connected to other population in Canada and Europe. Results of this study indicate a level of genetic diversity within the recently discovered Newfoundland population comparable to populations in other regions and a general lack of structure between Canadian populations and those in Europe.