Mask wearing, social distancing and other steps to stop COVID-19 have also curtailed influenza

We use the synthetic control method to analyze the effect of face masks on the spread of Covid-19 in Germany. Our identification approach exploits regional variation in the point in time when face masks became compulsory. Depending on the region we analyse, we find that face masks reduced the cumulative number of registered Covid-19 cases between 2.3% and 13% over a period of 10 days after they became compulsory. Assessing the credibility of the various estimates, we conclude that face masks reduce the daily growth rate of reported infections by around 40%. <<<

“When I go out now, I imagine that everyone is smoking, and I pick my path to get the least exposure to that smoke,” she told me. If that’s the case, I asked her, is it irrational to hold your breath when another person walks past you and you don’t have enough space to move away? “It’s not irrational; I do that myself,” she said. “I don’t know if it makes a difference, but in theory it could. It’s like when you walk through a cigarette plume.”