• Twitter removed Dr. Atlas’ tweet saying cloth masks don’t work 
  • https://nymag.com/intelligencer/2020/10/twitter-removes-scott-atlass-tweet-saying-masks-dont-work.html 
• • CDC Oct 2020 cloth masks recommended for community 
    • https://wwwnc.cdc.gov/eid/article/26/10/20-0948_article 
  • Unsubstantiated claims that masks save lives (based upon IHME unproven presumption that masks, even cloth masks in community, reduce deaths by “at least one third”) 
    • https://cepr.org/voxeu/columns/mask-mandates-save-lives 
    • https://www.statnews.com/2020/10/23/universal-mask-use-could-save-130000-lives-by-the-end-of-february-new-modeling-study-says/ 
  • 2020: CDC recommends community mask adoption 
    • https://www.cdc.gov/media/releases/2020/p0714-americans-to-wear-masks.html 
    • CDC’s own data showing poor efficacy of anything other than N95 
      • https://www.cdc.gov/library/covid19/pdf/2020-08-18-Science-Update_FINAL_public.pdf 
    • Gaiters and bandanas: 
      • “As a last resort, the agency said that health care providers could consider using “homemade masks” – such as bandanas or scarves – to care for coronavirus patients, ideally in combination with a face shield.” 
      • https://www.cnn.com/2020/03/19/health/hospital-coronavirus-shortages-preparedness/index.html 
      • https://www.cdc.gov/coronavirus/2019-ncov/hcp/ppe-strategy/face-masks.html 
      • https://www.bostonherald.com/2020/03/23/bandanas-can-substitute-as-coronavirus-masks-as-a-last-resort-says-cdc/  
    • Single layer masks (e.g., Gaiters and bandanas) no longer recommended 
      • https://www.cdc.gov/library/covid19/pdf/2020-08-18-Science-Update_FINAL_public.pdf 
      • https://bestlifeonline.com/cdc-face-masks-news/  
    • CDC concedes cloth masks not as effective (NYT) 
      • https://www.nytimes.com/2022/01/14/health/cloth-masks-covid-cdc.html  
    • Dec 2020 Military grade camera shows risk of airborne spread 
      • https://www.washingtonpost.com/investigations/2020/12/11/coronavirus-airborne-video-infrared-spread/  
    • “Wearing cloth masks will not have much effect” 
      • https://www.sciencedirect.com/science/article/pii/S2452199X20301481  
    • “The homemade cloth masks again yielded either no change or a significant increase in emission rate during speech compared to no mask” 
      • https://www.nature.com/articles/s41598-020-72798-7  
    • “A rigorous study finds that surgical masks are highly protective, but cloth masks fall short.” 
      • https://www.nature.com/articles/d41586-021-02457-y  
        • Note: the study found NO benefit of cloth masks, and surgical masks had some benefit in those >50 yr., but no benefit in <50 yr 
    • Even surgical masks not effective in high-risk settings 
      • https://www.science.org/doi/10.1126/science.abg6296  
      • https://pubmed.ncbi.nlm.nih.gov/34016743/ 
    • Bacterial and fungal isolation from face masks 
      • https://www.nature.com/articles/s41598-022-15409-x  
    • Dec 2021 onwards Dr Leana Wen: cloth masks not effective against airborne virus 
      • https://twitter.com/drleanawen/status/1473083590707662850 
      • https://twitter.com/drleanawen/status/1517235792787251206  
      • https://reason.com/2021/12/21/leana-wen-cloth-mask-facial-decorations-covid-cdc-guidance/ (has actual video) 
    • CDC mask study (expanded reanalysis by Dr. Høeg showing no benefit of school mandate) 
      • https://www.journalofinfection.com/article/S0163-4453(22)00550-3/fulltext 
      • https://www.the74million.org/article/study-masking-in-school-had-little-or-no-effect-on-student-covid-cases/ 
    • CDC updates mask recommendations 
      • https://www.washingtonpost.com/health/2022/01/10/cdc-weighs-n95-kn95-masks-guidance-omicron/ 
      • https://www.webmd.com/lung/news/20220115/cdc-updates-mask-guidelines-cloth-masks–least-effective 
      • https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/about-face-coverings.html  
    • Even in 2020 we had data showing that surgical masks were minimally effective and some cloth masks were ineffective 
      • https://www.health.harvard.edu/blog/masks-save-lives-heres-what-you-need-to-know-2020111921466 
      • https://www.cato.org/working-paper/evidence-community-cloth-face-masking-limit-spread-sars-cov-2-critical-review 
      • Dr. Osterholm (commentary that cloth masks provide very limited protection) 
        • https://www.cidrap.umn.edu/news-perspective/2020/07/commentary-my-views-cloth-face-coverings-public-preventing-covid-19 
    • Case against mask for children 
      • https://www.wsj.com/articles/masks-children-parenting-schools-mandates-covid-19-coronavirus-pandemic-biden-administration-cdc-11628432716  
    • Studies that suggest low quality masks increase risk of spread 
      • https://www.nature.com/articles/s41598-020-72798-7 
      • https://aip.scitation.org/doi/10.1063/5.0034580  
    • CA counties with mask mandate fared no better than those without 
      • https://www.sfgate.com/coronavirus/article/California-mask-mandates-delta-COVID-19-data-works-16502191.php 
    • CDC drops mask requirement in health care settings 2022 
      • https://www.webmd.com/lung/news/20220928/cdc:-masking-no-longer-required-in-health-care-settings 
      • However, CA continues mask mandate for health care settings 
    • Analysis of mask compliance in Europe fails to find benefit
      • https://www.cureus.com/articles/93826-correlation-between-mask-compliance-and-covid-19-outcomes-in-europe