COVID-19: UK only buying enough vaccines to protect the most vulnerable.

The UK is only buying a vaccine to protect the people most vulnerable to COVID-19.

Every vaccine bought for the UK stockpile since the summer has been on the assumption that just 30 million people - less than half the population - will get it.

With such low coverage, the virus would continue to spread and some form of social distancing would still be needed.

Watch video on channel "Sky News"