Mapping the Vector Abundance of Endemic Mosquito-Borne Diseases in Southern Quebec

Abstract

Background: Climate change is increasing the dispersion of mosquitoes and the spread of viruses of which some mosquitoes are the main vectors. This increases the risk of humans coming into contact with infected mosquitoes and developing diseases with sometimes fatal consequences. In Quebec, the surveillance and management of endemic mosquito-borne diseases, such as West Nile virus or Eastern equine encephalitis, could be improved by mapping the areas of risk supporting vector populations. However, there is currently no active tool tailored to Quebec that can predict annual mosquito population abundances.Methods: Our modelling approach is designed to meet this need. Four species of mosquitos were studied in this project for the period from 2003 to 2014 for the southern part of the province: Aedes vexans (VEX), Coquillettidia perturbans (CQP), Culex pipiens-restuans group (CPRg) and Ochlerotatus stimulans group (STMg) species. We used a mixed linear regression approach to model the abundances of each species or species groups as a function of meteorological and land cover variables.Results: The best models incorporate, for CPRg, the agricultural land, grassland and woodland classes and the average minimum temperature in September of the previous year; for STMg, the urban and woodland classes and the mean precipitation in June; for CQP, urban areas and the mean precipitation in January and August; and finally, for VEX, the agricultural land class and the mean precipitation in January, February and September.Conclusions: The models proved to be robust and precise over almost the entire study area, and the presence of significant climate variables for each of the species or species groups makes it possible to consider their use in predicting long-term spatial variations, based on climate and landscape change, in the abundance of mosquitoes potentially harmful to public health in southern Quebec.Manuscript intended for publication in International J. of Health Geographics