Bluetongue in Europe: vectors, epidemiology and climate change.

Bluetongue (BT) is an economically important disease of ruminants resulting from infection with bluetongue virus (BTV). Historically, BT outbreaks in Europe were rare and short-lived. However, during the last 10 years, BTV has become firmly established in southern Europe and, since 2006, has begun to occur in northern Europe. There is a substantial body of evidence linking this emergence to climate change. In this paper, we summarise the recent emergence of BTV in Europe, review the known links between climate and BTV transmission, and discuss gaps in our knowledge of the epidemiology of BT and how they might be filled by current and future research.