Wear a Mask! Just published in Nature Medicine: Respiratory virus shedding in exhaled breath and efficacy of face masks: "Our results indicate that surgical face masks could prevent transmission of human coronaviruses" https://www.nature.com/articles/s41591-020-0843-2
Respiratory virus shedding in exhaled breath and efficacy of face mask
A study of 246 individuals with seasonal respiratory virus infections randomized to wear or not wear a surgical face mask showed that masks can significantly reduce detection of coronavirus and...https://www.nature.com/articles/s41591-020-0843-2
We don't need the scientific proof. It takes too long for action.