To: Jeff Hayden who wrote (1385057 ) 12/29/2022 6:46:41 AM From: IC720 2 RecommendationsRecommended By
Read Replies (1) | Respond to Are Face Masks Effective? The Evidence.swprs.org Updated : July 2022Published: July 2020Share on : Twitter / Facebook A) Studies ? B) WHO review ? C) Real-world evidence ? D) N95/FFP2 masks ? E) Additional aspects ? F) The aerosol issue ? G) Contrary evidence ? H) Mask-related risks ? I) Conclusion ? So far, most studies found little to no evidence for the effectiveness of face masks in the general population, neither as personal protective equipment nor as a source control. A May 2020 meta-study on pandemic influenza published by the US CDC found that face masks had no effect, neither as personal protective equipment nor as a source control. ( Source ) A WHO review of ten randomized controlled trials of face masks against influenza-like illness, published in September 2019, found no statistically significant benefit. ( Source ) A Danish randomized controlled trial with 6000 participants, published in the Annals of Internal Medicine in November 2020, found no statistically significant effect of high-quality medical face masks against SARS-CoV-2 infection in a community setting. ( Source ) A large randomized controlled trial with close to 8000 participants, published in October 2020 in PLOS One , found that face masks “did not seem to be effective against laboratory-confirmed viral respiratory infections nor against clinical respiratory infection.” ( Source ) A February 2021 review by the European CDC found no high-quality evidence in favor of face masks and recommended their use only based on the ‘precautionary principle’. ( Source ) A July 2020 review by the Oxford Centre for Evidence-Based Medicine found that there is no evidence for the effectiveness of face masks against virus infection or transmission. ( Source ) A November 2020 Cochrane review found that face masks did not reduce influenza-like illness (ILI) cases, neither in the general population nor in health care workers. ( Source ) An August 2021 study published in the Int. Research Journal of Public Health found “no association between mask mandates or use and reduced COVID-19 spread in US states.” ( Source ) An experimental study using virus aerosols, published in May 2022 in the Journal of Infectious Diseases , found that only professionally fit-tested N95/FFP2 masks, but not surgical masks or non-fitted N95/FFP2 masks, reduced viral loads in nostrils. ( Source ) A large Spanish school study , published in March 2022, found that “mask mandates in schools were not associated with lower SARS-CoV-2 incidence or transmission.” ( Source ) A May 2020 article by researchers from Harvard Medical School , published in the New England Journal of Medicine, concluded that face masks offer “little, if any, protection”. ( Source ) A 2015 study in the British Medical Journal BMJ Open found that cloth masks were penetrated by 97% of particles and may increase infection risk by retaining moisture or repeated use. ( Source )
