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https://wwwnc.cdc.gov/eid/article/26/5/19-0994_article "... from literature published during 1946 - July 27, 2018. In pooled analysis, we found no significant reduction in influenza transmission with the use of face masks..."

https://steemit.com/mask/@theallstarr/masks-are-ineffective-70-year-meta-study-concludes