Herein, I argue that it is irresponsible for any government agency to require the use of a product or service that has not been at minimum reasonably conclusively demonstrated to be BOTH safe and effective. I have provided links to predominantly peer-reviewed sources upon which I base this opinion. It is not exhaustive, but I believe it is representative. Please read.
Let me be clear: Safety is just as important as efficacy. The middle of a pandemic is no time to be requiring a practice where the outcome of that practice is unknown. Masks -- generally cloth masks, but also surgical/hospital masks -- are simply NOT known to be safe any more than they are known to be effective. For all we know, mass public masking has caused more problems than it solved, and I can think of a number of scenarios why that might be the case; in fact, one of the (better, in my view) studies cited therein (MacIntyre et al.) found that healthcare workers who wore cloth masks had worse outcomes than the control group (masked or unmasked).
Ergo, I don't believe there was ever any warrant to assume that mass face mask use was a no-harm option. That has never been demonstrated.
Please note: I am not saying masks (cloth or surgical) are definitely not at all effective in preventing the transmission of viruses. I am not saying that masks (cloth or surgical) are unsafe or contribute to the transmission of viruses. I am saying that the evidence for either is, at best, inconclusive, and provides no warrant for mask mandates.
My opinion is based on my own public health experience (30+ years) and reading of the relevant literature, summarized here in four parts (I-IV).
I. The 1918-20 experience: My argument: There was never any historical precedent for requiring the use of face masks by the general public.
1918 (Primary):
https://ajph.aphapublications.org/doi/abs/10.2105/AJPH.10.1.34
“Studies made in the Department of Morbidity Statistics of the California State Board of Health did not show any influence of the mask on the spread of influenza in those cities where it was compulsorily applied, and the Board was, therefore, compelled to adopt a policy of mask encouragement, but not of mask compulsion. . . .The masks, contrary to expectation, were worn cheerfully and universally, and also, contrary to expectation of what should follow under such circumstances, no effect on the epidemic curve was to be seen.“
Their assumption was: “If we grant that influenza is a droplet borne infection, it would appear that the wearing of masks was a procedure based on sound reasoning and that results should be expected from their application.”
They assumed it was bacterial, which it wasn’t, and since viruses are far smaller than bacteria, there’s no reason to assume it’s droplet-borne.
Conclusions:
"When a sufficient degree of density in the mask is used to exercise a useful filtering influence, breathing is difficult and leakage takes place around the edge of the mask.. . .This leakage around the edges of the mask and the forcible aspiration of droplet laden air through the mask is sufficient to make the possible reduction in dosage of infection not more than 50 per cent effective.”
That is with bacteria, not the much smaller viruses.
Secondarily, this has been the conclusion for the last hundred years.
E.g.
https://www.washingtonpost.com/history/2020/04/02/everyone-wore-masks-during-1918-flu-pandemic-they-were-useless/
“Everyone wore masks during the 1918 flu pandemic. They were useless.”
Citing John Barry (The Great Influenza: The Story of the Deadliest Pandemic in History): “The masks worn by millions were useless as designed and could not prevent influenza,” Barry wrote. “Only preventing exposure to the virus could.”
E.g.
Arnold, Catharine. Pandemic 1918 (p. 14). St. Martin's Publishing Group. Kindle Edition.
“[T]he most distinctive image of Spanish flu is the mask. While the mask itself provided little protection from the disease, it has become the icon of the epidemic.” (p.13-14)
E.g.,
Kolata, Gina Flu: The Story Of The Great Influenza Pandemic of 1918 and the Search for the Virus that Caused It. Farrar, Straus and Giroux. Kindle Edition.
“They recall that citizens wore white gauze masks in public in a vain attempt to protect themselves.” (pp.52-53)
While not strictly dispositive, since no one wore masks during any epidemic since — e.g., 1957, 1968, or 2009 for that matter — one must assume that the standard public health and epidemiological opinion prior to 2020 was that masks did not work and have no use as a preventative measure.
II. Review/Meta-analytic articles (mostly pre-pandemic)
1. COMMENTARY: Masks-for-all for COVID-19 not based on sound data
Lisa M Brosseau, ScD, and Margaret Sietsema, PhD | Apr 01, 2020
https://www.cidrap.umn.edu/news-perspective/2020/04/commentary-masks-all-covid-19-not-based-sound-data
“We do not recommend requiring the general public who do not have symptoms of COVID-19-like illness to routinely wear cloth or surgical masks because:
There is no scientific evidence they are effective in reducing the risk of SARS-CoV-2 transmission”
Note 1: In an addendum they note: “The authors and CIDRAP have received requests in recent weeks to remove this article from the CIDRAP website.” Such is the state of science today.
Note 2: However, despite their clear findings: “Despite the current limited scientific data detailing their effectiveness, we support the wearing of face coverings by the public when mandated and when in close contact with people whose infection status they don't know.” Such is the state of science today.
2. Universal Masking in Hospitals in the Covid-19 Era
Michael Klompas, M.D., M.P.H., Charles A. Morris, M.D., M.P.H., Julia Sinclair, M.B.A., Madelyn Pearson, D.N.P., R.N., and Erica S. Shenoy, M.D., Ph.D.
https://www.nejm.org/doi/full/10.1056/NEJMp2006372
“We know that wearing a mask outside health care facilities offers little, if any, protection from infection. Public health authorities define a significant exposure to Covid-19 as face-to-face contact within 6 feet with a patient with symptomatic Covid-19 that is sustained for at least a few minutes (and some say more than 10 minutes or even 30 minutes). The chance of catching Covid-19 from a passing interaction in a public space is therefore minimal. In many cases, the desire for widespread masking is a reflexive reaction to anxiety over the pandemic.“
They suggest two scenarios where masks may benefit, but both are in clinical contexts.
3. 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
https://wwwnc.cdc.gov/eid/article/26/5/19-0994_article (CDC’s web site, btw)
Upshot: “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.”
“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.”
“By intention-to-treat analysis, facemask use did not seem to be effective against laboratory-confirmed viral respiratory infections (odds ratio [OR], 1.4; 95% confidence interval [CI], 0.9 to 2.1, p = 0.18) nor against clinical respiratory infection (OR, 1.1; 95% CI, 0.9 to 1.4, p = 0.40). Similarly, in a per-protocol analysis, facemask use did not seem to be effective against laboratory-confirmed viral respiratory infections (OR 1.2, 95% CI 0.9–1.7, p = 0.26) nor against clinical respiratory infection (OR 1.3, 95% CI 1.0–1.8, p = 0.06).”
4. The use of masks and respirators to prevent transmission of influenza: a systematic review of the scientific evidence
Faisal bin-Reza,aVicente Lopez Chavarrias,bAngus Nicoll,a,bMary E. Chamberland
https://archive.vn/obDeD#selection-1633.0-1771.11
“None of the studies established a conclusive relationship between mask ⁄ respirator use and protection against influenza infection.”
5. Effectiveness of Masks and Respirators Against Respiratory Infections in Healthcare Workers: A Systematic Review and Meta-Analysis
Vittoria Offeddu, Chee Fu Yung, Mabel Sheau Fong Low, Clarence C Tam
Clinical Infectious Diseases, Volume 65, Issue 11, 1 December 2017, Pages 1934–1942, https://doi.org/10.1093/cid/cix681
This did find some protective effect of masks and N95 respirators among healthcare workers:
“Meta-analysis of randomized controlled trials (RCTs) indicated a protective effect of masks and respirators against clinical respiratory illness (CRI) (risk ratio [RR] = 0.59; 95% confidence interval [CI]:0.46–0.77) and influenza-like illness (ILI) (RR = 0.34; 95% CI:0.14–0.82). Compared to masks, N95 respirators conferred superior protection against CRI (RR = 0.47; 95% CI: 0.36–0.62) and laboratory-confirmed bacterial (RR = 0.46; 95% CI: 0.34–0.62), but not viral infections or ILI.”
NOTE: This applied to bacterial infections, no viral infections. Further:
“However, the existing evidence is sparse and findings are inconsistent within and across studies. “
III. Individual studies
1. A cluster randomised trial of cloth masks compared with medical masks in healthcare workers
C Raina MacIntyre, Holly Seale1, Tham Chi Dung, Nguyen Tran Hien, Phan Thi Nga, Abrar Ahmad Chughtai, Bayzidur Rahman, Dominic E Dwyer, Quanyi Wang
https://bmjopen.bmj.com/content/5/4/e006577
“The rates of all infection outcomes were highest in the cloth mask arm, with the rate of ILI statistically significantly higher in the cloth mask arm (relative risk (RR)=13.00, 95% CI 1.69 to 100.07) compared with the medical mask arm. Cloth masks also had significantly higher rates of ILI compared with the control arm. An analysis by mask use showed ILI (RR=6.64, 95% CI 1.45 to 28.65) and laboratory-confirmed virus (RR=1.72, 95% CI 1.01 to 2.94) were significantly higher in the cloth masks group compared with the medical masks group. Penetration of cloth masks by particles was almost 97% and medical masks 44%.
2. Facemask against viral respiratory infections among Hajj pilgrims: A challenging cluster-randomized trial
Mohammad Alfelali, Elizabeth A. Haworth, et al.
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0240287
"In this large-scale cluster-randomized controlled trial (cRCT) we sought to assess the effectiveness of facemasks against viral respiratory infections. . .By intention-to-treat analysis, facemask use did not seem to be effective against laboratory-confirmed viral respiratory infections (odds ratio [OR], 1.4; 95% confidence interval [CI], 0.9 to 2.1, p = 0.18) nor against clinical respiratory infection (OR, 1.1; 95% CI, 0.9 to 1.4, p = 0.40). Similarly, in a per-protocol analysis, facemask use did not seem to be effective against laboratory-confirmed viral respiratory infections (OR 1.2, 95% CI 0.9–1.7, p = 0.26) nor against clinical respiratory infection (OR 1.3, 95% CI 1.0–1.8, p = 0.06)."
3. Study on respirators versus masks hailed as landmark
https://www.cidrap.umn.edu/news-perspective/2009/09/study-respirators-versus-masks-hailed-landmark
The study, which involved close to 2,000 hospital staffers in Beijing, showed that N95 respirators reduced the risk of respiratory illness by a significant 60% and the risk of confirmed influenza by 75%, whereas surgical masks had no effect.
Note 1: Surgical masks had no effect, and are far better than ordinary cloth masks.
Note 2: "MacIntyre's study "illustrates how there is no protection from surgical masks, so I hope it'll discourage people from saying there is protection," Brosseau said."
Note 3: "There's a really big problem with retrospective studies," she said. "How do you know that people really did wear those masks, and how much do you know about their exposure? Really in the end, what it's arguing is that putting anything on your face is an improvement over putting nothing on your face."
IV. Recent studies.
I'll be honest: I don't trust any analyses done in the last year for two reasons: A) Data quality is incredibly poor, and B) There is significant political incentive to find an effect, and significant political disincentive to find no effect.
Examples:
1. Decrease in Hospitalizations for COVID-19 after Mask Mandates in 1083 U.S. Counties
Dhaval Adjodah, Karthik Dinakar, Samuel P. Fraiberger, George W. Rutherford, David V. Glidden, Monica Gandhi
https://www.medrxiv.org/content/10.1101/2020.10.21.20208728v2
Withdrawn: "The authors have withdrawn this manuscript because there are increased rates of SARS- CoV-2 cases in the areas that we originally analyzed in this study. New analyses in the context of the third surge in the United States are therefore needed and will be undertaken directly in conjunction with the creators of the publicly-available databases on cases, hospitalizations, testing rates."
2. Identifying airborne transmission as the dominant route for the spread of COVID-19
Renyi Zhang, View ORCID ProfileYixin Li, Annie L. Zhang, Yuan Wang, and Mario J. Molina
"The mitigation measures are discernable from the trends of the pandemic. Our analysis reveals that the difference with and without mandated face covering represents the determinant in shaping the trends of the pandemic. This protective measure significantly reduces the number of infections."
This has been challenged:
https://metrics.stanford.edu/sites/g/files/sbiybj13936/f/files/pnas_loe_061820_v3.pdf
"....the claims in this study were based on easily
falsifiable claims and methodological design flaws. We present only a small selection of the most
egregious errors here. Given the scope and severity of the issues we present, and the paper’s outsized and
immediate public impact, we ask that the Editors of PNAS retract this paper immediately and reassess the
Contributed Submission editorial process by which it was published."
While they "agree that mask-wearing plays an
important role in slowing the spread of COVID-19" this is, I feel, the usual boilerplate to demonstrate their political cred.
Similarly: https://ncrc.jhsph.edu/research/identifying-airborne-transmission-as-the-dominant-route-for-the-spread-of-covid-19/
"While masks most likely prevent community spread of COVID-19, this highly flawed paper provides no evidence on mask effectiveness at the population level. The study also provides no information to demonstrate that airborne transmission — let alone “long-range airborne transmission” — is the dominant form of COVID-19 transmission. The claims made in this paper are not supported, and the journal editors should strongly consider retraction."
3. The hair salon study
https://www.cdc.gov/mmwr/volumes/69/wr/mm6928e2.htm
Absence of Apparent Transmission of SARS-CoV-2 from Two Stylists After Exposure at a Hair Salon with a Universal Face Covering Policy — Springfield, Missouri, May 2020
M. Joshua Hendrix, MD1; Charles Walde, MD2; Kendra Findley, MS3; Robin Trotman, DO
Personally, I don't find this compelling at all. Interesting, yes; compelling, no. It is simply assumed that the masking was the key factor in lack of transmission, and note that less than half of the exposed people were even tested. It is simply unknown whether or to what extent masks had anything do do with any apparent lack of viral transmission.