白宫负责新冠的Dr. Jha说世界上没有一个研究表明口罩有多大用

Biden COVID Czar FINALLY Admits the Truth About Masks

"There is no study in the world that shows a masks work that well," admitted Dr. Ashish Jha. "You're never going to get the kind of benefit from mandatory year-round masking as you would from making substantial improvements in indoor air quality. Plus, it's a lot easier to implement as well."