The WHO is working with China to try and pinpoint the source of SARS- COV-2. Sian Griffiths, Emeritus Professor of Public Health at the Chinese University of Hong Kong says there are lessons we can learn from the investigation she led into the original SARS outbreak back in 2003. That inquiry revealed how SARS had spread from bats to humans via civet cats.

A Covid-19 vaccine claims to be 90% effective. It uses genetic material, messenger RNA. Daniel Anderson of Harvard MIT Health Science tells us about the huge potential of mRNA to provide treatments for many medical conditions.

However, rolling out such a vaccine globally faces a huge range of economic and practical obstacles as ethicist Nicole Hassoun of Binghamton University explains.

And a unique experiment shows despite a vast range of precautions including being isolated US Marines have contracted Covid -19. Stuart Sealfon, Professor of Neurology at Mount Sinai Hospitals says this study shows we need testing to be integrated more thoroughly into everyday life and that many of the precautions we currently use may not be enough to prevent transmission.

(Image: Credit: Getty Images)

Presenter: Roland PeaseProducer: Julian Siddle