Edited by JoyahMengayah at 19-12-2023 01:08 PM
We now have the most authoritative estimate of the value provided by wearing masks during the pandemic: approximately zero. The most rigorous and extensive review of the scientific literature concludes that neither surgical masks nor N95 masks have been shown to make a difference in reducing the spread of Covid-19 and other respiratory illnesses.
This verdict ought to be the death knell for mask mandates, but that would require the Centers for Disease Control (CDC) and the rest of the public-health establishment to forsake “the science”—and unfortunately, these leaders and their acolytes in the media seem as determined as ever to ignore actual science.
Before the pandemic, clinical trials repeatedly showed little or no benefit from wearing masks in preventing the spread of respiratory illnesses like flu and colds. That was why, in their pre-2020 plans for dealing with a viral pandemic, the World Health Organization, the CDC, and other national public-health agencies did not recommend masking the public. But once Covid-19 arrived, magical thinking prevailed.
Officials ignored the previous findings and plans, instead touting crude and easily debunked studies purporting to show that masks worked.
The gold standard for medical evidence is the randomized clinical trial, and the gold standard for analyzing this evidence is Cochrane (formerly the Cochrane Collaboration), the world’s largest and most respected organization for evaluating health interventions. Funded by the National Institutes of Health and other nations’ health agencies, it’s an international network of reviewers, based in London, that has partnerships with the WHO and Wikipedia. Medical journals have hailed it for being “the best single resource for methodologic research” and for being “recognized worldwide as the highest standard in evidence-based healthcare.”
It has published a new Cochrane review of the literature on masks, including trials during the Covid-19 pandemic in hospitals and in community settings. The 15 trials compared outcomes of wearing of surgical masks versus wearing no masks, and also versus N95 masks. The review, conducted by a dozen researchers from six countries, concludes that wearing any kind of face covering “probably makes little or no difference” in reducing the spread of respiratory illness. It may seem intuitive that masks must do something. But even if they do trap droplets from coughs or sneezes (the reason that surgeons wear masks), they still allow tiny viruses to spread by aerosol even when worn correctly—and it’s unrealistic to expect most people to do so. While a mask may keep out some pathogens, its inner surface can also trap concentrations of pathogens that are then breathed back into the lungs. Whatever theoretical benefits there might be, in clinical trials the benefits have turned out to be either illusory or offset by negative factors.
Oxford’s Tom Jefferson, the lead author of the Cochrane review, summed up the real science on masks: “There is just no evidence that they make any difference. Full stop.” This lack of evidence would be enough to keep any new drug or medical treatment from being approved—much less one whose purported benefits had not even been weighed against the harmful side effects. As the Cochrane reviewers disapprovingly note, few of the clinical trials of masks even bothered to collect data on the harmful effects on subjects. Most public-health officials and journalists have ignored the downsides, too, and social-media platforms have censoredevidence of those harms. But there’s no doubt, from dozens of peer-reviewed studies, that masks cause social, psychological, and medical problems, including a constellation of maladies called “mask-induced exhaustion syndrome.”
Yet public-health officials, in violation of the first-do-no-harm principle, continue recommending or mandating masks without good evidence of their effectiveness or any pretense of cost-benefit analysis. Masks are still required in many hospitals and other institutions.
Despite all the data showing that Covid-19 poses virtually no risk to healthy children, the CDC continues to recommend masking all students in communities where infection rates are rising. While the WHO advises against masks for children under six, and the European Union advises against them for students under 12, the CDC cruelly recommends masking everyone from age two on up.
The CDC’s director, Rochelle Walensky, remains determined to ignore the best research on masks, as she made clear in a congressional hearing earlier this month.
“Our masking guidance doesn’t really change with time,” she said when asked how the new review from Cochrane would affect the agency’s policies. “This is an important study,” she conceded, “but the Cochrane review only includes randomized clinical trials, and, as you can imagine, many of the randomized clinical trials were for other respiratory viruses.”
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Post time 15-12-2023 12:31 AM
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Post time 15-12-2023 05:45 AM
