If the world is ever to return to anything like normality, experts agree we need to find a vaccine for COVID-19 as soon as possible. Scientists across the globe are working towards just that – with more than a hundred vaccines now at various stages of development, and a handful of those already being trialed in humans.

On this week's Agenda with Stephen Cole, we examine the hunt for a COVID-19 vaccine, and consider when we might find that golden bullet.

Jerome Kim, Director General of the International Vaccines Institute in Seoul explained to us exactly how you go about looking for a vaccine, and described the unprecedented efforts going into finding a solution to the crisis.

We also speak to Wu Xiaohong – an English teacher in Wuhan, and her son, Lu Genglin – both of whom are taking part in a vaccine trial in their home city – where the virus was first detected.

And we hear from Stephen Kissler at the Harvard School of Public Health and Evan H Bloch from the Johns Hopkins School of Medicine – who tell us just why a vaccine is so vital – and detail some of the other therapies being used in the battle against coronavirus.