The Cochran Review is a highly respected publication, giving evidence-based examinations of numerous health issues. Since 2010, it has been undertaking a review of the literature dealing with various physical interventions, such as masks, to stop the spread of viruses. Here is what was concluded about masks in general, explicitly addressing the Covid-19 issue: “There is uncertainty about the effects of face masks. The low to moderate certainty of evidence means our confidence in the effect estimate is limited, and that the true effect may be different from the observed estimate of the effect. The pooled results … did not show a clear reduction in respiratory viral infection with the use of medical/surgical masks. There were no clear differences between the use of medical/surgical masks compared with N95/P2 respirators in healthcare workers when used in routine care to reduce respiratory viral infection. Hand hygiene is likely to modestly reduce the burden of respiratory illness, and although this effect was also present when … laboratory‐confirmed influenza was analysed separately, it was not found to be a significant difference for the latter two outcomes.”
The mask mandate was implemented without adequate scientific testing, using one study which was subject to criticism. Listed below, after the following extract, is a tweet by a doctor, giving references to the past literature indicating that even in surgical settings, masks are quite limited in preventing the passage of viruses, and mainly stop particles being spread. This is highly relevant since at any point the mask mandate could be rolled back into force, and since people accepted it, unlike the mass rejection done during the 1918 Spanish (really Chinese) flu.