| further studies on bluetongue and bluetongue-related orbiviruses in the sudan. | the seasonal incidence of bluetongue virus (btv) in central sudan is related primarily to fluctuations in the prevalence of the vector, culicoides imicola. population densities of this midge begin to rise with the onset of precipitation and peak during october, before falling sharply at the end of the rainy season in november. these are also the months of btv transmission. populations of c. schultzei, the commonest midge in central sudan, are also related to the rainy season but this species doe ... | 1990 | 2174372 |