As coronavirus continues to spread around the world, face masks are in high demand as people look for ways to protect themselves.
But do they really protect most people from contracting the virus?
Dr Shunmay Yeung from London School of Hygiene and Tropical Medicine explains.
Please note: This video was produced on 13 March 2020 and based on the advice available from the World Health Organization and other health groups at the time.
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