> What data do you have that show that masks don't have a statistical impact on spread, mortality, or both?
From the 1918-1920 Spanish influenza pandemic onward, public health agencies have evaluated the effects of mask mandates and other non-pharmaceutical interventions. The consistent result of these epidemiological studies has been failure to detect a positive effect. A typical review article, which was I think the most quoted up until 2020 is Cowling (https://pubmed.ncbi.nlm.nih.gov/20092668/).
From the discussion:
In conclusion there remains a substantial gap in the scientific literature on the effectiveness of face masks to reduce transmission of influenza virus infection. While there is some experimental evidence that masks should be able to reduce infectiousness under controlled conditions, there is less evidence on whether this translates to effectiveness in natural settings. There is little evidence to support the effectiveness of face masks to reduce the risk of infection.
From the 1918-1920 Spanish influenza pandemic onward, public health agencies have evaluated the effects of mask mandates and other non-pharmaceutical interventions. The consistent result of these epidemiological studies has been failure to detect a positive effect. A typical review article, which was I think the most quoted up until 2020 is Cowling (https://pubmed.ncbi.nlm.nih.gov/20092668/).
From the discussion:
In conclusion there remains a substantial gap in the scientific literature on the effectiveness of face masks to reduce transmission of influenza virus infection. While there is some experimental evidence that masks should be able to reduce infectiousness under controlled conditions, there is less evidence on whether this translates to effectiveness in natural settings. There is little evidence to support the effectiveness of face masks to reduce the risk of infection.