Thursday, August 12, 2021

Do Masks Help?

8/11/21 City Journal:
Surgical masks were designed to keep medical personnel from inadvertently infecting patients’ wounds, not to prevent the spread of viruses. Public-health officials’ advice in the early days of Covid-19 was consistent with that understanding. Then, on April 3, 2020, Adams announced that the CDC was changing its guidance and that the general public should hereafter wear masks whenever sufficient social distancing could not be maintained.

Fast-forward 15 months. Rand Paul has been suspended from YouTube for a week for saying, “Most of the masks you get over the counter don’t work.” Many cities across the country, following new CDC guidance handed down amid a spike in cases nationally caused by the Delta variant, are once again mandating indoor mask-wearing for everyone, regardless of inoculation status. The CDC further recommends that all schoolchildren and teachers, even those who have had Covid-19 or have been vaccinated, should wear masks.

The CDC asserts this even though its own statistics show that Covid-19 is not much of a threat to schoolchildren. Its numbers show that more people under the age of 18 died of influenza during the 2018–19 flu season—a season of “moderate severity” that lasted eight months—than have died of Covid-19 across more than 18 months. What’s more, the CDC says that out of every 1,738 Covid-19-related deaths in the U.S. in 2020 and 2021, just one has involved someone under 18 years of age; and out of every 150 deaths of someone under 18 years of age, just one has been Covid-related. Yet the CDC declares that schoolchildren, who learn in part from communication conveyed through facial expressions, should nevertheless hide their faces—and so should their teachers....

t’s striking how much the CDC, in marshalling evidence to justify its revised mask guidance, studiously avoids mentioning randomized controlled trials. RCTs are uniformly regarded as the gold standard in medical research, yet the CDC basically ignores them apart from disparaging certain ones that particularly contradict the agency’s position. In a “Science Brief” highlighting studies that “demonstrate that mask wearing reduces new infections” and serving as the main public justification for its mask guidance, the CDC provides a helpful matrix of 15 studies—none RCTs. The CDC instead focuses strictly on observational studies completed after Covid-19 began. In general, observational studies are not only of lower quality than RCTs but also are more likely to be politicized, as they can inject the researcher’s judgment more prominently into the inquiry and lend themselves, far more than RCTs, to finding what one wants to find....

With these different methods of analysis in mind, it becomes easier to evaluate the 14 RCTs, conducted around the world, that have tested the effectiveness of masks in reducing the transmission of respiratory viruses. Of these 14, the two that have directly tested “source control”—the oft-repeated claim that wearing a mask benefits others—are a good place to start.

A 2016 study in Beijing by MacIntyre, et al. that claimed to find a possible benefit of masks did not prove very informative, as only one person in the control group—and one in the mask group—developed a laboratory-confirmed infection. Much more illuminating was a 2010 study in France by Canini, et al., which randomly placed sick people, or “index patients,” and their household contacts together into either a mask group or a no-mask control group. The authors “observed a good adherence to the intervention,” meaning that the index patients generally wore the furnished three-ply masks as intended. (No one else was asked to wear them.) Within a week, 15.8 percent of household contacts in the no-mask control group and 16.2 percent in the mask group developed an “influenza-like illness” (ILI). So, the two groups were essentially dead even, with the sliver of an advantage observed in the control group not being statistically significant. The authors write that the study “should be interpreted with caution since the lack of statistical power prevents us to draw formal conclusion regarding effectiveness of facemasks in the context of a seasonal epidemic.” However, they state unequivocally, “In various sensitivity analyses, we did not identify any trend in the results suggesting effectiveness of facemasks.”...

A 2010 study by Larson, et al. in New York found that those in the hand-hygiene group were less likely to develop any symptoms of an upper respiratory infection (42 percent experienced symptoms) than those in the mask-plus-hand-hygiene group (61 percent). This statistically significant finding suggests that wearing a mask actually undermines the benefits of hand hygiene.

A multivariable analysis of this same study found a significant difference in secondary attack rates (the rate of transmission to others) between the mask-plus-hands group and the control group. On this basis, the authors maintain that mask-wearing “should be encouraged during outbreak situations.” However, this multivariable analysis also found significantly lower rates in crowded homes—“i.e., more crowded households had less transmission”—which tested at a higher confidence level. Thus, to the extent that this multivariable analysis provided any support for masks, it provided at least as much support for crowding.

Other RCTs cited demonstrate that masks are not demonstrated to be effective.  A few show at best that masks are inferior to social distancing and regular handwashing.  What started out as a recognized bad idea soon became public health theater (like TSA after 9/11).  Now it is just the exercise of raw power to scare the fearful and remind us peasants that only the elite are exempt from rules.

But the children.  8/10/21 NPR has a big scary headline:

Nearly 94,000 Kids Got COVID-19 Last Week. They Were 15% Of All New Cases

Buried in the article:
One big question for parents — whether delta is making kids sicker than previous strains — still has no clear answer.
But the numbers appear to show that severe illness, hospitalization and death are rare in children infected with the coronavirus.
In states where data was available, less than 2% of all child COVID-19 cases required hospitalization and 0.00% to 0.03% were fatal.
"I'm not seeing any patterns that suggest the virus is more virulent or more serious or more severe in children than it was before this variant appeared," Maldonado added.
Still, the growing number of children hospitalized with COVID-19 could further strain an already overburdened pediatric health care system.
Many children's hospitals are not only dealing with patients who've contracted the coronavirus but also kids with issues indirectly related to the pandemic. Many children have developed mental health problems stemming from social isolation, and others deferred medical care during the peak of the outbreak last year.

4 comments:

  1. "The CDC further recommends that all schoolchildren and teachers, even those who have had Covid-19 or have been vaccinated, should wear masks.

    The CDC asserts this even though its own statistics show that Covid-19 is not much of a threat to schoolchildren."

    But it is a threat to the kids' grandparents, who they will take it home to.

    My state had over 5000 new cases yesterday. Our biggest hospital has roped off a parking garage floor and is using it as additional hospital space for the overflow. We have lost literally thousands of nurses due to overwork stress. It looks like the Civil War. Because the idiots here won't get a shot or wear a mask or wash their hands or stay out of crowds. If you have a more effective solution than whining about how the current suppression attempts aren't working, we'd all be glad to hear it.

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    Replies
    1. If masks do not help, why require them? Focus on what does work and is less annoying: hand washing and social distancing.

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    2. My post said nothing about requiring masks. :)

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    3. "Because the idiots here won't get a shot or wear a mask or wash their hands or stay out of crowds." You seem to be saying that masks will help.

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