Covid: Scientists concern over scale of mutation

Scientists are concerned about the new coronavirus variant because it has mutated so much from the original virus and seems to be more contagious.

Prof Emma Thomson from COG-UK, which has been mapping changes in the virus, told BBC World News: "The key thing about this new variant is that normally we would expect perhaps one or two changes in the virus per month, but this new variant that has popped up actually has 17 changes in it, which is really quite a large increase."