Covid-19: how effective are face masks, really?

Since the start of the pandemic, face coverings and their ability to prevent the transmission of Covid-19 have been under constant scrutiny by scientists, politicians and the public. More than a year and a half in, what do – and don’t – we know? Madeleine Finlay speaks to Prof Cath Noakes about how effective different face coverings are, how best to use them, and when we should be masking-up. Help support our independent journalism at theguardian.com/sciencepod