> If 50% of students in a classroom get infected after 2 days in school while wearing masks then, IMHO, masks can't be all that effective in the first place. I

> If 50% of students in a classroom get infected after 2 days in school while wearing masks then, IMHO, masks can't be all that effective in the first place. I believe the primary assertion has always been that making protects others more than it protects oneself. So I wouldn't consider this a contradiction of that. That said, it's entirely possible that the 50% of students who didn't get infected were wearing superior masks. Or, perhaps 80% of the students would have been infected if no one had worn masks. In short, you can't really draw a meaningful "see masks don't work" conclusion from this.