Assessing the consequences of an incursion of a vector-borne disease I. Identifying feasible incursion scenarios for bluetongue in Scotland.

Following the arrival of bluetongue virus serotype 8 (BTV-8) in southeast England in September 2007, the Scottish Government commissioned research to assess the economic consequences of a BTV-8 incursion to Scotland. Here we present the first component of the assessment, which entailed identifying feasible incursion scenarios for the virus. Our analyses focused on three routes of introduction: wind-borne dispersal of infected vectors, import of infected animals and northwards spread of BTV from affected areas in GB. These analyses were further refined by considering the spatial and temporal variation in the probability of onward transmission from an initial incursion.