Among the roughly 178,000 individuals who were encouraged to wear them, the scientists found that mask-wearing increased by almost 30 percent and that the change in behavior persisted for 10 weeks or more. After the program was instituted, the researchers reported an 11.9 percent decrease in symptomatic Covid symptoms and a 9.3 percent reduction in symptomatic seroprevalence, which indicates that the virus was detected in blood tests. While the effect may seem small, the results offer a glimpse of just how much masks matter, Mobarak said. "A 30-percent increase in mask-wearing led to a 10 percent drop in Covid" he said. - https://www.nbcnews.com/science/science-news/largest-mask-study-yet-details-importance-fighting-covid-19-rcna1858

The study itself at https://www.poverty-action.org/sites/default/files/publications/Mask_RCT____Symptomatic_Seropositivity_083121.pdf states, ""

There were 178,288 individuals in the intervention group and 163,838 individuals in the control group. The intervention increased proper mask-wearing from 13.3% in control villages (N=806,547 observations) to 42.3% in treatment villages (N=797,715 observations) (adjusted percentage point difference = 0.29 [0.27, 0.31]). This tripling of mask usage was sustained during the intervention period and two weeks after. Physical distancing increased from 24.1% in control villages to 29.2% in treatment villages (adjusted percentage point difference = 0.05 [0.04, 0.06]). After 5 months, the impact of the intervention faded, but mask-wearing remained 10 percentage points higher in the intervention group. The proportion of individuals with COVID-like symptoms was 7.62% (N=13,273) in the intervention arm and 8.62% (N=13,893) in the control arm. 7.44 8.47

https://www.kansascity.com/opinion/editorials/article244839757.html - Kansas tested whether mask mandates decrease COVID-19 cases. The results were clear - 8/10/20 - "Those with mask orders have seen cases decline from about 26 to 16 per 100,000 population. Cases in counties with no mask mandate have stayed relatively flat."

CDC's definition of close contact: "Someone who was within 6 feet of an infected person for a cumulative total of 15 minutes or more over a 24-hour period* starting from 2 days before illness onset (or, for asymptomatic patients, 2 days prior to test specimen collection) until the time the patient is isolated." https://www.cdc.gov/coronavirus/2019-ncov/php/contact-tracing/contact-tracing-plan/appendix.html#contact The general view among infectious disease experts, including those from the World Health Organization (WHO), is that this strongly indicates that SARS-CoV-2 is not highly airborne transmissible, except possibly under certain circumstances.

If masks work, why did a woman wearing a mask with windows down get it from someone else?https://www.sfgate.com/news/article/A-nurse-and-her-entire-family-contracted-covid-19-15775645.php

Jeremy Hammond exposes fraudulent study on masks in PNAS - https://www.jeremyrhammond.com/2020/07/10/study-fraudulently-claims-sars-cov-2-is-mainly-airborne/

A 4,800 person randomized trial (https://www.medpagetoday.com/blogs/vinay-prasad/89778) in Denmark showed that mask have limited value in protecting against COVID.

https://www.greenmedinfo.com/blog/why-won-t-anyone-publish-danish-mask-study - Why Won’t Anyone Publish the Danish Mask Study? 11/16/20

RFK, Jr. and Jeremy Hammond video on masks - https://www.jeremyrhammond.com/2020/10/28/my-chat-with-rfk-jr-on-sars-cov-2-lockdowns-and-masks/

https://www.msn.com/en-us/news/world/dutch-govt-will-not-advise-use-of-masks/ar-BB17l46I - Dutch government will not advise public to wear masks - minister - 7/29/20

“The Dutch government says it will not advise the public to wear masks to slow the spread of coronavirus, asserting that their effectiveness has not been proven.”

https://www.thetimes.co.uk/article/facemask-evidence-is-astonishingly-weak-says-architect-of-swedish-strategy-bm0w335zr - ‘Dangerous’ to think masks will stop virus - 8/10/20

https://www.bloomberg.com/news/articles/2020-07-28/sweden-unveils-promising-covid-19-data-as-new-cases-plunge - Sweden Unveils ‘Promising’ Covid-19 Data as New Cases Plunge - 7/28/20

“Tegnell also broached the subject of face masks. “With numbers diminishing very quickly in Sweden, we see no point in wearing a face mask in Sweden, not even on public transport,” he said. ”

CDC study states "Although mechanistic studies support the potential effect of hand hygiene or face masks, evidence from 14 randomized controlled trials of these measures did not support a substantial effect on transmission of laboratory-confirmed influenza. We similarly found limited evidence on the effectiveness of improved hygiene and environmental cleaning."

https://wwwnc.cdc.gov/eid/article/26/5/19-0994_article

Mercola and friends on masks - https://articles.mercola.com/sites/articles/archive/2020/07/19/are-face-masks-effective.aspx

New England Journal of Medicine "We know that wearing a mask outside health care facilities offers little, if any, protection from infection." https://www.nejm.org/doi/full/10.1056/NEJMp2006372 Michael Klompas, M.D., M.P.H., et al Universal Masking in Hospitals in the Covid-19 Era N Engl J Med 2020; 382 5/21/2020