How did the nasty sheep and cattle disease, bluetongue, gain a foothold in northern Europe? It now seems that calves might play a key role, but this raises further questions about where the latest form of the virus sprang from.
The BTV8 strain of the bluetongue virus appeared in Belgium in 2006. No one knows how it arrived, but instead of dying away over the winter along with the midges that carry it, the virus somehow survived and invaded much of north-west Europe in 2007. It is expected to resume spreading soon, as the weather warms.
According to the UK’s…
