Bluetongue virus serotype 8 epidemic in north-western Europe in 2006: Preliminary findings

In the middle of August 2006, North-western Europe was shaken by the start of an extensively propagating Bluetongue (BT) epidemic. BT is an arthropod-borne viral noncontagious disease of domestic and wild ruminants, particularly affecting sheep with severe clinical disease and mortality. To date, 24 different BT-serotypes have been identified and the disease is transmitted by biting midges (Culicoides). Soon after the start of the epidemic it was determined that BT virus serotype 8 was involved. BTV8 is new to this European region. The gene sequence is closely related to an isolate from sub-Saharan Africa (Nigeria) from the beginning of the 1980s. BTV-8 has also been found in Pakistan/India, Africa, and the Caribbean. This paper describes the specific aspects of the BTV8 epidemic: onset and course of the epidemic, clinical findings, spatial spread, vector surveillance, the effect of wind on the spread of BTV8, control measures taken and the possibilities for vaccination.