Using climate data to map the potential distribution of Culicoides imicola(Diptera : Ceratopogonidae) in Europe

Culicoides imicola, a vector of bluetongue virus and African horse sickness virus, is principally Afro-Asian in distribution, but has recently been fo und in parts of Europe. A logistic regression model based on climate data ( temperature, saturation deficit, rainfall and altitude) and the published d istribution of C. imicola in Iberia was developed and then applied to other countries in Europe, to identify locations where C. imicola could become e stablished. The model identified three temperature variables as significant determinants of the distribution of C. imicola in Iberia (minimum of the m onthly minimum temperatures, maximum of the monthly maximum temperatures an d number of months per year with a mean temperature greater than or equal t o 12.5 degreesC). The model indicated that under current conditions, the di stribution of C. imicola in Spain, Greece and Italy could be extended and t he vector could potentially invade parts of Albania, Yugoslavia, Bosnia and Croatia. To simulate the effect of global warming, temperature values in t he model were increased by 2 degreesC. Under these conditions, the potentia l spread of C. imicola in Europe would be even more extensive.