Part 3: Masks
Alex Berenson
I wish masks worked.
I wish masks worked…
I wish masks worked…
I wish masks worked…
I wish masks worked…
I wish masks worked…
I wish masks worked….
I wish masks worked.
But they don’t.
“aerosols:” particle less than 5 microns
Coronovirus (single virion of Sars-Cov-2): 60-140 nanometers (0.1 microns)
Filtration Performance of FDA-Cleared Surgical Masks
Samy Rengasamy1 , Adam Miller1 , Benjamin C. Eimer2 , and Ronald E. Shaffer
CONCLUSIONS
Dust masks are not approved by NIOSH and should not be used in workplaces for respiratory protection against particulate, because the level of protection they provide cannot be assured as evidenced by the large variability seen in tests of filtration performance. Users of dust masks should be cautioned against using them for protection against particulate in the nano- or ultrafine size ranges.
EMERGING INFECTIOUS DISEASES
Volume 26, Number 5—May 2020
Policy Review
Nonpharmaceutical Measures for Pandemic Influenza in Nonhealthcare Settings—Personal Protective and Environmental Measures
Jingyi Xiao1, Eunice Y. C. Shiu1, Huizhi Gao, Jessica Y. Wong, Min W. Fong, Sukhyun Ryu, and Benjamin J. Cowling
Author affiliations: University of Hong Kong, Hong Kong, China
We did not find evidence that surgical-type face masks are effective in reducing laboratory-confirmed influenza transmission, either when worn by infected persons (source control) or by persons in the general community to reduce their susceptibility
Meta-analysis of risk ratios for the effect of face mask use with or without enhanced hand hygiene on laboratory-confirmed influenza from 10 randomized controlled trials with >6,500 participants. A) Face mask...
Effectiveness of Adding a Mask Recommendation to Other Public Health Measures to Prevent SARS-CoV-2 Infection in Danish Mask Wearers
A Randomized Controlled Trial
Henning Bundgaard, DMSc, Johan Skov Bundgaard, BSc
ABSTRACT:
Conclusion:
The recommendation to wear surgical masks to supplement other public health measures did not reduce the SARS-CoV-2 infection rate among wearers by more than 50% in a community with modest infection rates, some degree of social distancing, and uncommon general mask use. The data were compatible with lesser degrees of self-protection
Journal of Aerosol Science
Volume 40, Issue 3, March 2009, Pages 256-269
Size distribution and sites of origin of droplets expelled from the human respiratory tract during expiratory activities
L.MorawskaaG.R.JohnsonaZ.D.RistovskiaM.HargreavesaK.MengersenaS.CorbettbC.Y.H.ChaocY.LidD.Katoshevskie
The majority of droplets from human expiratory activities are very small, being in low micrometer and high sub-micrometer ranges. Where Papineni and Rosenthal found that 80-90% of droplets were smaller than1 um, the current study agrees, showing that these smallest particles are located within an aerosol mode, centered in the range 0.1–1 um…
Kevin P Fennelly
Vol 8 September 2020
Discussion
This
Viewpoint suggests that infection control guidelines should be re-evaluated to
account for the predominance of small particles within infectious aerosols.
Protective devices available to health-care workers have a range of protection,
increasing from surgical masks to filtering facepiece respirators to powered
air-purifying respirators. Although these are indicated for close encounters,
their limitations highlight the need for improved administrative controls, such
as more rapid diagnosis and isolation, and the development of vaccines and
treatments. These data support calls for the recognition of aerosol (ie,
traditional airborne) transmission of SARS-CoV-2.144 This could facilitate the
use of enhanced dilution and directional ventilation and other environmental
control options—eg, air disinfection with ultraviolet germicidal
irradiation,145 which might be especially helpful in congregate settings such
as nursing homes. Implementation of improved infection control measures could
prevent future morbidity and mortality among health-care workers.
Interim guidance
5 June 2020
World Health Organization
Advice to decision makers on the use of masks for the general public
Many countries have recommended the use of fabric masks/face coverings for the general public. At the present time, the widespread use of masks by healthy people in the community setting is not yet supported by high quality or direct scientific evidence and there are potential benefits and harms to considerBETWEEN:
St. Michael’s Hospital and The Ontario Hospital Association
and
The Ontario Nurses’ Association
Before: William Kaplan
Sole Arbitrator
The matters in dispute proceeded to a hearing in Toronto on August 9 and October 31, 2016, February 3, April 6, 29, 30, May 1, June 1, 2, 22, August 22, September 30, October 28, 29, and December 11, 2017, April 19, 21, 22, May 4, and July 16, 23, 2018.
Masking – Not a Solution
There is no persuasive evidence establishing a conclusive relationship between the use of surgical and procedural masks and protection against influenza transmission.
…the preponderance of the masking evidence is compelling – surgical and procedural masks are extremely limited in terms of source control: they do not prevent the transmission of the influenza virus. The two masks introduced into evidence clearly demonstrate why that would be the case. What protection they provide is self-evidently limited by their construction and how they sit on a human face.
Conclusion
Ultimately, I agree with Arbitrator Hayes: “There is scant scientific evidence concerning asymptomatic transmission, and, also, scant scientific evidence of the use of masks in reducing the transmission of the virus to patients”
REFERENCES:
Major Study Finds Masks Don’t Reduce COVID-19 Infection RatesNOVEMBER 18, 2020 By Jordan Davidson
WUHAN VIRUS
Many Studies Find That Cloth Masks Do Not Stop Viruses Like COVID
A thorough marketing campaign for the use of low-quality masks has convinced millions of people that masks will reduce COVID-19 spread, but do they really?
By Lisa Mair
NOVEMBER 23, 2020
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