Yes, masks reduce the risk of spreading Covid, despite a review saying they don’t

Do face masks really work to reduce Covid transmission? C Raina MacIntyre and Abrar Ahmad Chughtai, UNSW Sydney; David Fisman, University of Toronto, and Trish Greenhalgh, University of Oxford take a look at the evidence The question of whether and to what extent face masks work to prevent respiratory infections such as Covid and influenza