Mask stuff isn't cut and dry. The US medical community scoffed at Asian countries for many years over mask wearing during cold and flu season. The CDC, up until the summer had it right on their recommendations page, in a general population setting the wearing of any mask, other than a properly fitted N-95 respirator, (not mask), does not provide protection against airborne viruses. This was on their website long after they were calling for masks for all. There have been 0 landmark studies in the last year to have changed that.
There is still debate within the medical community on the effectiveness of masks during surgery. The science isn't settled there. You can go on Pub- Med and read peer reviewed studies both for and against.
Read the stuff from CIDRAP. All kinds of information, no conclusion on scientific proof that masks work. A lot of opinions and studies. Nothing conclusive for or against. Central theme through a lot of it is there is no concrete scientific proof either way, most of them think "it's a good idea" and you should really concetrate on distancing with situation avoidance to really make a difference. A few links below. There is a lot more there if you want to look it up.
www.cidrap.umn.edu
www.cidrap.umn.edu
www.cidrap.umn.edu
www.cidrap.umn.edu
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