The paper doesn't actually say that. It says nobody really knows basic things you'd need to determine that, for example: Given how little is known about the pr

The paper doesn't actually say that. It says nobody really knows basic things you'd need to determine that, for example: Given how little is known about the production and airborne behavior of infectious respiratory droplets, it is difficult to define a safe distance for social distancing There are plenty of scientists saying masks have no effect when worn by people who aren't actually both visibly sick and working in healthcare: https://www.cidrap.umn.edu/news-perspective/2020/04/commentary-masks-all-covid-19-not-based-sound-data https://www.cidrap.umn.edu/news-perspective/2020/04/commenta... In fact manufacturers of ear loop/cloth masks specifically say they can't stop COVID: https://off-guardian.org/wp-content/medialibrary/EYZu2Q2X0AA9A9x-800x800.jpg https://off-guardian.org/wp-content/medialibrary/EYZu2Q2X0AA... The WHO said: https://www.foxnews.com/world/who-guidance-healthy-people-wear-masks-around-coronavirus-patients https://www.foxnews.com/world/who-guidance-healthy-people-we... "If you do not have any respiratory symptoms such as fever, cough or runny nose, you do not need to wear a mask," Dr. April Baller, a public health specialist for the WHO, says in a video on the world health body's website posted in March. "Masks should only be used by health care workers, caretakers or by people who are sick with symptoms of fever and cough." There's plenty of contradictory research out there. Maybe a mask helps if you're literally coughing up phlegm all over the place, but COVID has a dry cough and obviously symptomatic people don't seem to be the only way it spreads.