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All current evidence is that masks have a minor effect, measured in tiny fractions of a percent. https://vinayprasadmdmph.substack.com/p/do-masks-reduce-risk h

• ricardobeat 5y ago
  The recent Bangladesh study with 350k people found a ~10% reduction in cases, from only 40% mask adoption. The two-cities trial early in 2020 in Germany saw a ~20% reduction. Those are in the number of infections - the number looks low but can make a massive difference in the actual transmission rate. In the German case, after a month infections dropped close to zero.
  • deleted 5y ago
    [deleted]
  • midasuni 5y ago
    Cases in Scotland with mask laws and Hugh adherence seem higher than in England which doesn’t have laws and has low adherence. Be interesting if anyone has done a proper comparison between say Glasgow and Manchester.
    • ricardobeat 5y ago
      I think I’ve heard that before, but how is it higher? From the usual dashboards Scotland has 130 cases per million, while England is at 150/million. The number of cases right now is also stable while the UK overall is going up?
      • ed_balls 5y ago
        it's hard to compare cases without knowing how many tests were done and how they are administered.
        • ralusek 5y ago
          And where in a particular wave a given place is. And what the seroprevalence and other demographic factors are between the two populations.
      • midasuni 5y ago
        I last checked a couple of weeks ago when Scotland was on 370/100k and England on 350/100k, seemed to have flipped back the other way now
  • kyrra 5y ago
    That study is flawed in many ways. And one thing to point out, if you do take the study at face value, cloth mask do virtually nothing, only surgical masks did something ( AKA the intervention group). The study was not blind, so the intervention group (those that wore surgical masks and showed the large efficacy increase) we're paid money to be part of the group. The non-intervention groups (cloth and control) did not receive any monetary compensation. Recording of masking was done via people observing mask wearing, which also could potentially mess with the data ( as this was not blind). Reporting of covid symptoms was entirely based on the population manually reporting it, there was no random testing to see variances in covid. Only around 30 to 40% of cases were actually verified via a test. The education that came with the intervention group may have caused the older population to stop going out as much, which impacted the result. My take is that the study proved you could pay people to mask, but it's efficacy result is dubious. CATO has a meta analysis about mask studies that is interesting (pre print still): https://www.cato.org/working-paper/evidence-community-cloth-face-masking-limit-spread-sars-cov-2-critical-review https://www.cato.org/working-paper/evidence-community-cloth-...
    • ricardobeat 5y ago
      I'm pretty sure the cloth masks debacle was settled sometime around Q1 2020, a year and a half ago. Anyone arguing about this needs to find a better hobby. They've been not recommended, or explicitly banned from airlines and other places, for a long time. They just confirmed this in a very rigorous controlled study. > were paid money to be part of the group That's simply not true. This is the document describing the intervention to raise mask usage: https://docs.google.com/document/d/1mgY6k5SooeMt6PIqwx-7z5LZR70wqXMqLhKjnCLJJ9k/edit https://docs.google.com/document/d/1mgY6k5SooeMt6PIqwx-7z5LZ... It says they tested monetary & non-monetary incentives, but if you look at the execution table, it's all "Public Reinforcement". The conclusion was that Nudges and incentives outside of the core NORM [1] intervention had no effect on mask-wearing.. > Recording of masking was done via people observing mask wearing This is good. It means they observed the overall effect on the entire population. Some previous studies relied on self-reporting which is not as reliable. > Only around 30 to 40% of cases were actually verified via a test. You can't force people to take a test. But the rate of positives within the ones that agreed to collection was similar to the overall self-reported one. The study goes into this at length. There is a whole section trying out a different approach where they assign the average soropositivity to non-consenters, instead of excluding them, and that makes the results even stronger. > The education that came with the intervention group may have caused the older population to stop going out as much, which impacted the result. That sounds like a very random hypothesis. I can come up with another dozen of these. Maybe it rained more? Too cold? Maybe there was a soap opera on, that 60 year olds love to watch? You'd think a dozen scientists from Yale, Stanford, Berkeley, John Hopkins & others would find a way to control studies for external factors... if it was this easy to challenge results you could do it for basically every paper ever published. The paper is available for free here: https://www.poverty-action.org/sites/default/files/publications/Mask_Second_Stage_Paper_20211108.pdf.pdf https://www.poverty-action.org/sites/default/files/publicati... [1] no cost, offering, reinforcing, modelling
• fragmede 5y ago
  Here's a link to a real actual science study that used tuberculosis-sized particles and found filtration efficiencies of 99.5% or higher by N95 masks. Which isn't minor. It's been over a year. If you're not using an N95, you're doing yourself and those around you a disservice. https://pubmed.ncbi.nlm.nih.gov/9487666/ https://pubmed.ncbi.nlm.nih.gov/9487666/
  • planetsprite 5y ago
    I don't disagree with you on the effectiveness of masks but tuberculosis bacterial cells are far larger than coronavirons.
    • tenuousemphasis 5y ago
      Coronavirus itself isn't airborne, it travels in aerosolized water droplets, which are significantly larger than coronavirus itself.
      • wrycoder 5y ago
        But which are in the airbourne size range.
  • nradov 5y ago
    And so what are you suggesting? Everyone wear N95 masks all the time forever?
    • spookthesunset 5y ago
      There is no end game to masking. It will be in perpetuity in some places.
      • deleted 5y ago
        [deleted]
    • NikolaNovak 5y ago
• msie 5y ago
  "In October 2021, Prasad prompted social media controversy when he published a blog post comparing the U.S. COVID-19 pandemic response to the beginnings of Hitler's Third Reich. Bioethicist Arthur L. Caplan said that Prasad's arguments were specious and ignorant, and science historian Robert N. Proctor said that Prasad was "overplaying the dangers of vaccination mandates and trivializing the genuine harms to liberty posed by 1930s fascism"." https://en.wikipedia.org/wiki/Vinay_Prasad https://en.wikipedia.org/wiki/Vinay_Prasad
• Klinky 5y ago
  Vinay Prasad seems to be a contrarian who recently compared the US COVID-19 policies to Hitler's Germany[1]. In the article you linked, he's citing his own study on cloth masks. Most would agree that cloth masks are the least effective masking option at stopping viral spread. Cloth masking is just the easiest target to attack in an anti-mask agenda. He also implies doctor's have inherent bias against HCQ and Ivermectin, while being pro-mask. Basically the dude has his own biases and agenda here, and the study he cites isn't a definitive nail against mask wearing. 1. https://vinayprasadmdmph.substack.com/p/how-democracy-ends https://vinayprasadmdmph.substack.com/p/how-democracy-ends
  • timr 5y ago
    > In the article you linked, he's citing his own study on cloth masks. This is a blog post summarizing his review of every study on masks ever conducted. So yes, he's citing that. You should read it. I linked to it because most people won't have time to read 30,000 words on masks, and want the TL;DR. Everything else you've said is an ad hominem.
    • Klinky 5y ago
      His review is targeting the weakest mask type while cherry picking and downplaying even from studies showing benefits of masking, such as the Bangladesh study others have cited, to paint the picture he wants to paint.
      • timr 5y ago
        Read past the title. It covers all masks, not just cloth facemasks.
        • Klinky 5y ago
          I have. I've skimmed through the PDF, and it seems he wants to highlight the "ineffectiveness" of cloth masks, and downplay benefit from other types. It is also odd to put "cloth masks" in the title, if that is not the main focus of the review.
• markdown 5y ago
  > To date, I'm aware of no study that has quantified a difference in infection, hospitalization or death that is attributable to travel bans. Why would you need a study to tell you that if nobody with covid travels to a country, that country remains covid-free? Perhaps you are unaware, but there are countries on this planet that covid hasn't gotten to, and those countries have travel bans.
  • Robotbeat 5y ago
    Yup, this is such a huge pet peeve of mine. Throwing away science in the name of empiricism. What I mean by that is that science is about understanding the world by being able to make certain empirically verified models (mathematical usually), and then using the validated models (such as the germ theory of disease) to predict what the results would be even if we haven’t already measured that exact thing. Like, because of an experiment done on Wednesday, a piece of meat kept carefully covered with metal is not going to sprout maggots and flies. Because maggots and flies are caused by flies laying eggs. That same piece of knowledge can then be used to predict with decent certainty that you’re still not going to sprout maggots and flies if you cover it with glass instead of metal and do it on a Tuesday. Germ theory of diseases says if you quarantine travel, you can prevent (or reduce probability of) novel COVID diseases sprouting up in your country. Because the disease is caused by germs carried by infected people during the few weeks they’re contagious. You don’t need an exact study to prove that, although it’d certainly be nice. Seriously. Empiricism is great. Using a kind of mindless empiricism (“models don’t tell you anything, so unless every situation is measured, you have no idea”) to throw doubt on science is not.
    • titzer 5y ago
      The same applies to "lockdowns don't work." That is obviously complete BS considering there are plenty of examples of lockdowns that did work (e.g. the Aug 2020 lockdown of Victoria, NZ lockdowns, Taiwan, South Korea). But lockdowns can fail easily with noncompliance and inability to effectively quarantine the infected. It's like saying boats don't work after trying to build one out of grocery bags or untreated plywood. Yeah, crappy boats are going to have leaks. Lockdowns are hard; it's not something we really practice (and worse, there are malicious defectors who want lockdowns to fail). A lot of people, we have learned, are selfish and unwilling or unable to make any sacrifice, even in the face of severe collective consequences, and worse, will sabotage efforts either for political gain or just the sheer pleasure of watching everyone else fail (and die!). I really don't know how we can expect global society to continue given how craven some people are.
• titzer 5y ago
  > To date, I'm aware of no study that has quantified a difference in infection, hospitalization or death that is attributable to travel bans. You have got to be joking, because NZ, Taiwan, and Australia all achieved COVID zero by effectively quarantining their countries, i.e. travel bans. It's basic logic that viruses cross borders and oceans via infected people, not by wafting magically through the air. That said, travel bans are only effective in the very early phase, when infections are near zero. The US, Europe, and most of Asia are highly connected and by the time COVID infections were spreading, it was pretty much too late. Also, the US's travel bans were not particularly ineffective. Like the US's entire response, haphazard, half-hearted, and actively opposed by lots of weaponized ignorance.