Coronavirus vaccine update: How far is the developement?

Scientists across the world are working around the clock to develop a vaccine against the coronavirus - from China to the United States, Germany and Britain. New technologies are helping speed things up and more than a hundred potential vaccines are in development. Some are already at an advanced stage and are being tested on volunteers. The pace may be unprecedented, but there's still a long way to go in the battle against the outbreak. We take a look at some of the methods, old and new, that scientists are using to get there.