Influences of vector biology on transmission of arboviruses and outbreaks of disease: the Culicoides brevitarsis model.

The use of a model to appraise arboviral epizootics is described, and examples are given which demonstrated long-distance wind-dispersal of the biting-midge vector Culicoides brevitarsis from the same endemic source. Vector abundance is characterised by peaks and troughs of abundance, the patterns of which vary between localities and annually. Short term climatic effects can change rapidly the age structure of a population, thus increasing the number of midges that can transmit a virus and profoundly influencing the probabilities of viral transmission. The population dynamics of vector and viral foci are complex, if not chaotic.