It actually does. When used/worn properly.Whilst I see your point, the bit of material (often unwashed) over someone’s face, sadly doesn’t make a blind bit of difference to catching the virus or not.
Effectiveness of public health measures in reducing the incidence of covid-19, SARS-CoV-2 transmission, and covid-19 mortality: systematic review and meta-analysis
Objective To review the evidence on the effectiveness of public health measures in reducing the incidence of covid-19, SARS-CoV-2 transmission, and covid-19 mortality. Design Systematic review and meta-analysis. Data sources Medline, Embase, CINAHL, Biosis, Joanna Briggs, Global Health, and...
www.bmj.com