Summary
Between 2000 and 2003, thousands of light-trap collections for Culicoides were made throughout Italy and a detailed distribution map of the primary vector of bluetongue (BT) virus (BTV), C. imicola compiled. In some areas, however, where clinical BT occurred and C. imicola could not be captured, the virus was isolated from biting midges belonging to the Obsoletus and/or the Pulicaris Complexes. Thus, the distribution and abundance of these two species complexes in Italy, as determined from about 3 000 collections, are reported here also and compared to that of C. imicola (from about 24 000 collections). The probable spread of the main vector of BT, C. imicola, into the northern third of Italy, and the widespread prevalence of additional vectors of the Obsoletus and Pulicaris Complexes, indicate nearly all regions of Italy to be at some risk to incursions of BTV. However, these complexes comprise at least six and twelve species, respectively, so precisely which species are able to transmit BTV remains incompletely known.

Keywords
Bluetongue, Culicoides imicola, Italy, Obsoletus Complex, Pulicaris Complex.