Routes to the development of a parapoxvirus vaccine for red squirrels (ENRR645)

The UK population of the native red squirrel Sciurus vulgaris has fallen dramatically over the past 150 years, so much so that red squirrels are already locally extinct in many parts of England and Wales. This decline in the reds has in part been blamed on the concomitant increase in grey squirrels Sciurus carolinensis which were introduced to the UK from America in the mid-nineteenth century. There can be little doubt that the reason for the decline in red squirrel numbers is multi-factorial, but there is a growing body of evidence that a disease caused by a parapoxvirus (PPV) may play a major role in the local collapse of red squirrel populations.