Using GIS methods to assess bio-geographic and climatic effects on the vector capacity of Culex tarsalis for West Nile virus in the Inter-mountain West.


Geographic Information System (GIS) methods will be used to better understand the influence of bio-geographic and climatic factors on the transmission capability of the culicine mosquito, Culex tarsalis, for West Nile virus (WNV). GIS will be used to access and compile an array of bio-geographic and climatic data (GIS coverages) for areas with populations of Culex tarsalis in Inter-mountain West. Comparison of environmental profiles for habitats with and without C. tarsalis and GARP (Genetic Algorithm for Rule-set Prediction) analysis will be used to define ecologic niches and the geographic distribution of populations, thus establishing a basis for predicting risk of exposure to West Nile virus. Ambient temperature data will be used to determine variability in extrinsic incubation periods for WNV in female mosquitoes on a spatial scale relative to season, elevation, and latitude. Larval development sites will be identified and characterized using remote sensing and GIS methods and used to develop an understanding of seasonal population abundance and female overwintering capacity. These GIS approaches and procedures represent use of new technologies that provide new opportunities for identifying C. tarsalis populations that range from the most to least to efficient vectors of WNV in the Inter-mountain West.