Danish study of masks (whose authors couldn’t get it published until now) finds them insufficient against COVID-19

Conclusion:

The recommendation to wear surgical masks to supplement other public health measures did not reduce the SARS-CoV-2 infection rate among wearers by more than 50% in a community with modest infection rates, some degree of social distancing, and uncommon general mask use. The data were compatible with lesser degrees of self-protection.

https://www.acpjournals.org/doi/10.7326/M20-6817

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