> A report in Nature explained that researchers running a randomized controlled trial (RCT) of community mask use in Bangladesh “began by developing a strategy to promote mask wearing, with measures such as reminders from health workers in public places. This ultimately tripled mask usage, from only 13% in control villages to 42% in villages where it was encouraged”, and “then compared numbers of COVID-19 cases in control villages and the treatment communities”. They found that the number of infections in mask wearing communities decreased, with a reduction of COVID symptoms using surgical masks to 0.87 times the incidence in unmasked communities, and 0.91 times when using cloth masks.
Unfortunately they have misquoted the numbers here. Surgical masks reduced the prevalence of COVID-like symptoms by 11%, and of actual confirmed COVID cases by 9.5%, while cloth masks did about half as well [0]. So tripling the number of people wearing masks up to about 40% of the population has a very mild effect on COVID spread, and this is before Omicron. I don't think this makes a good case for mask mandates in 2022.