The first randomized controlled trial1,2 to assess the effectiveness of surgical face masks against SARS-CoV-2 infection specifically — which journals initially refused to publish — is finally seeing the light of day.
The so-called “Danmask-19 Trial,” published November 18, 2020, in the Annals of Internal Medicine,3 included 3,030 individuals assigned to wear a surgical face mask and 2,994 unmasked controls. Of them, 80.7% completed the study.
To qualify, participants had to spend at least three hours per day outside the home and not be required to wear a mask during their daily work. At the end of the study, participants reported having spent a median of 4.5 hours per day outside the home.
For one month, participants in the mask group were instructed to wear a mask whenever they were outside their home. Surgical face masks with a filtration rate of 98% were supplied. In accordance with recommendations from the World Health Organization, participants were instructed to change their mask after eight hours.
Antibody testing was performed before the outset and at the end of the study period. At the end of the month, they also submitted a nasal swab sample for PCR testing. What the Danmask-19 Trial Found
The primary outcome was a positive PCR test, a positive antibody test result (IgM or IgG) during the study period, or a hospital-based diagnosis of COVID-19. Secondary end points included PCR evidence of infection with other respiratory viruses.
Based on the adherence scores reported, 46% of participants always wore the mask as recommended, 47% predominantly as recommended and 7% failed to follow recommendations. So, what did they find? As you might expect, there’s a reason why the researchers had such a hard time getting this study published:
– Among mask wearers, 1.8% (42 participants) ended up testing positive for SARS-CoV-2, compared to 2.1% (53) among controls. When they removed the people who reported not adhering to the recommendations for use, the results remained the same — 1.8% (40 people), which suggests adherence makes no significant difference.
– 1.4% (33 participants) tested positive for antibodies compared to 1.8% (44) of controls.
– Among those who reported wearing their face mask “exactly as instructed,” 2% (22 participants) tested positive for SARS-CoV-2 compared to 2.1% (53) of the controls.
– 52 participants in the mask group and 39 in the control group reported COVID-19 in their household. Of these, two participants in the mask group and one in the control group developed SARS-CoV-2 infection — a finding that suggests “the source of most observed infections was outside the home.”
– 0.5% (nine participants) in the mask group and 0.6% (11 individuals) tested positive for one or more respiratory viruses other than SARS-CoV-2 (secondary outcome).
Masks May Lower, or Raise, Infection Risk
All in all, this landmark COVID-19-specific study failed to deliver good news to those who insist face masks are a crucial component of the pandemic response. Masks may reduce your risk of SARS-CoV-2 infection by as much as 46%, or it may increase your risk by 23%. In other words, the preponderance of evidence still shows that masks have virtually no impact on viral transmission.
Another take-home point that you get from this study, which Del Bigtree points out in The Highwire video report above, is that the vast majority — 97.9% of those who didn’t wear masks, and 98.2% of those who did — remained infection free.
So, we are destroying economies and lives around the world, for what, exactly? To protect a small minority from getting a positive PCR test result which, as detailed in “Asymptomatic ‘Casedemic’ Is a Perpetuation of Needless Fear <https://articles.mercola.com/sites/articles/archive/2020/11/19/covid-testing-fraud-fuels-casedemic.aspx>,” means little to nothing. As reported by the authors:4
*“Although no statistically significant difference in SARS-CoV-2 incidence was observed, the 95% CIs are compatible with a possible 46% reduction to 23% increase in infection among mask wearers.*
*These findings do offer evidence about the degree of protection mask wearers can anticipate in a setting where others are not wearing masks and where other public health measures, including social distancing, are in effect …*
*Transmission of SARS-CoV-2 may take place through multiple routes. It has been argued that for the primary route of SARS-CoV-2 spread — that is, via droplets — face masks would be considered effective, whereas masks would not be effective against spread via aerosols, which might penetrate or circumnavigate a face mask. Thus, spread of SARS-CoV-2 via aerosols would at least partially explain the present findings …*
*The present findings are compatible with the findings of a review of randomized controlled trials of the efficacy of face masks for prevention (as personal protective equipment) against influenza virus …*
*Our results suggest that the recommendation to wear a surgical mask when outside the home among others did not reduce, at conventional levels of statistical significance, the incidence of SARS-CoV-2 infection in mask wearers in a setting where social distancing and other public health measures were in effect, mask recommendations were not among those measures, and community use of masks was uncommon.”*
Date: Sat, 12 Dec 2020 16:47:21 -0500
From: Beldar Conehead
Subject: Re: Chatham Chatlist #6866