Corona-zona

  Last Thursday an item crossed my news feed entitled The CDC's Mask Mandate Study: Debunked . We here at Crona-zona are generally pro-mask; however, we are also open to persuasion. So, I decided to look into the claims made in the article. Its target is the CDC's  Morbidity and Mortality Monthly Repor t published in February, which concluded that mask mandates reduced COVID-19 hospitalizations. The third paragraph offers sarcastic  faux  praise of the CDC for publishing an erratum correcting the initial version of the report. It was admirable that the CDC did this, said the author, because the first version was "plagued with inaccuracies."  Even with corrections, the report is no good, according to the  fourth paragraph: " En face , CDC’s conclusion on mandates might appear to make sense unless one is familiar with the scientific data pertaining to the ineffectiveness of masking for prevention of the spread of Covid-19." In other words, it makes sense, but...

  On Tuesday NY Times Columnist Bret Stephens ran an op-ed  where he dripped contempt for people who said masks work. He thinks we all owe him and other anti-maskers a big fat apology. He cites a new review of scientific literature as evidence that masks really don't work. He quotes one of the study's authors (an epidemiologist who I suppose he interviewed) as saying there is no evidence that masks work, and no evidence that hand washing and air filtration work either. He then whines about how badly the anti-maskers were treated when they were right all along. No mention of poor treatment of pro-maskers. I guess it's OK since they were wrong all along? Here's the thing. Look at the "plain language summary" written by the authors of the   actual study :  We are uncertain whether wearing masks or N95/P2 respirators helps to slow the spread of respiratory viruses based on the studies we assessed. Hand hygiene programmes may help to slow the spread of respiratory ...

A recent study has concluded that lockdowns don't work. It is being bandied-about by conservative media as proof that other pandemic mitigation measures like masks don't work either. The study  is a meta-analysis, which statistically combines the results of other, smaller studies to gain  power to detect differences. It was done by some some economists—not epidemiologists.  It was published in a journal that is not peer-reviewed and was founded by a coauthor of the paper. That guy also happens to be a fellow at the arch-conservative Cato Institute. Talk about motivated reasoning. Public health experts criticized the study , saying it used an squishy definition of lockdowns. It also did not properly account for complex disease processes such as the wide variation in time it takes for infected people to die. Despite this, Rand Paul wasted no time taking the study at face value, claiming that lockdowns do more harm than good. He also said that masks don't work. Wait...wasn...

  A team of mechanical engineers and chemists from the University of Wisconsin at Madison (UW) have a cool study in pre-print (meaning it's not been peer-reviewed yet).  They set up a bunch mannequins in an actual classroom (as pictured above).  They configured some of the mannequins' pie-holes to exhale aerosols and others to inhale the surrounding air.  They actually tried several different scenarios for placing the exhalers and inhalers, which you can read about in the paper if you're interested. The aerosols they used were salt particles engineered to be about the same size as aerosolized SARS-CoV-2 particles.  They note that the concentration of particles was higher than someone with COVID-19 would actually emit, but they had to do this to ensure they could measure the test aerosols (signal) above the aerosols naturally present in the room (noise). To test transmission, they put different masks on the dummies:  4-layer commercial cotton masks, cloth m...

  Last month I did a post about some guy trying to "debunk" masks by providing us with all the devastating scientific evidence that masks don’t work. Turns out that, on careful examination, his scientific evidence was bunk.  People like this try to " baffle 'em with bullshit ," counting on most people not knowing how to read the studies they cite and/or being too lazy to do so.   A few days ago I saw a story about a study proving that masks are harmful.   It was published in an outlet called Medical Hypotheses. That journal publishes ideas, not actual research, so their articles don't "prove" anything.   The author claimed to be affiliated with Stanford.   Stanford has said he is not affiliated with them. You can draw your own conclusions regarding what that says about his credibility. I looked at the abstract, which says there is no scientific evidence of masks’ effectiveness. That is straight-up wrong.  Look here . Readers, I don’t have...

A paper just published in the journal Science  shows, once again, that masks are effective at mitigating SARS-CoV-2 transmission.  The twist on this study was that they looked at masks' effectiveness as a function of how virus-rich an environment is. They found that "surgical masking achieves large reductions in infection probability when the maskless infection probability is low, but increasingly smaller reductions when the maskless infection probability is high."   So in other words, masks work extremely well when the viral load is low, and less well when the viral load is high, as you'd expect. They found similar results for N95 masks, which are about an order of magnitude better at preventing infection.   They also considered different combinations of who is wearing a mask. Again, as you'd expect, the found that effectiveness was highest when there is "universal masking," next highest when someone emitting the virus is masked, and next highest when ...

  A new study  is—as far as I know—the first truly controlled field experiment on mask effectiveness. The conclusion is that masks work.  We already knew masks work because you can see it for yourself . But it's one thing to see that masks block droplets and another to know that this translates into meaningful protection at the community level. This latest study involved 600 villages in Bangladesh, which have a combined population of 342,126 adults. Researchers randomly selected some of the villages to be in the treatment group and the rest were in the control group.   For eight weeks, people in the treatment villages received free masks, information on the importance of masking, role modeling by community leaders, and in-person reminders. Villages in the control group received none of that. Researchers visited the villages every week over the study period to observe how many people were properly wearing masks and social distancing at mosques, markets, the ...

  Earlier this month the CDC released a study on the effectiveness of mask requirements in schools in preventing the spread of COVID-19. It was conducted by researchers from ASU, the CSC, Maricopa and Pima counties, and the Arizona Department of Education. (Where is AzDHS?) The researchers compared schools with "early mask requirements"—i.e., in place before school started—to those with "late mask requirements" (instituted after school started) to those with no mask requirements.  Usable data were collected from 999 of 1,041 (96.0%) of K–12 public non-charter schools in Maricopa and Pima counties. The results show that—guess what—masks work. Here is a chart derived from numbers presented in a main results table in the study: In other words, schools without mask mandates were three times more likely to have an our break as schools with mask mandates. Actually the figure is a little higher. Quoting the CDC report: "After adjusting for potential described confoun...

  In a previous post , I reported on research studying how well different kinds of masks block SARS-CoV-2 aerosols. The research is still under review, but used a very cool design that you can read about in the previous post if you're interested. None of the masks did a great job on their own, especially the ones we see everyone wearing. Cotton masks had 7.5% efficiency, and blue procedure masks  came in at 15.8%.   But the research found that the performance of all of them could be boosted by use of an appliance called a mask fitter or mask brace .  They boosted the filtration efficiency of inexpensive melt-blown polypropylene procedure masks  up north of 90%! This got my attention. So I decided to obtain and test Fix the Mask and Badger Seal. Both work by pressing the mask down around your nose and face, where masks tend to gap and leak. I have not received any incentives to do these reviews. The mannequin in the pictures below is not masked because I tho...

  I started this blog one year ago today. Well OK, there were a couple posts in December 2020, but that was a false start. Regular daily posts started on January 6, 2021. That's perhaps an inauspicious birthday because it's the same day T**** directed a treasonous mob to stage an insurrection at the Capitol. Anyway, as it says in the "about the blog," I started it because I was kind of obsessing about the  pandemic and reading all I could about it. The blog functioned as an outlet for all the information I was consuming as I was hunkering down at home, and I thought it might be of some modest help to others. One year ago, I never dreamed that I would still be blogging a year later! Like a lot of other people I was kind of naïve, thinking that with the vaccines coming the Apocalypse would be over in a few of months. Just goes to show how wrong a person can be. I've enjoyed writing all of the posts (284 including this one) I've done. This is a kind of writing ac...

 A  study  released by the CDC in October concluded that masks (among other mitigation measures) helped reduce COVID-19 incidence in Arizona by 75 percent.  Back in the spring, Governor Ducey not only refused to put a statewide mask mandate in place, he signed an order preventing local governments from doing so.  Infections soared, as shown in the this screenshot of positive test percentage by day (from the very useful ASU Biodesign  dashboard ; Xs are daily values, the red line is a 7 day trailing average, and the grey line is cumulative positive tests): Then in late June, after Arizona had been  the worst place in the world  for coronavirus infections for several weeks, the governor  rescinded the order , local ordinances were enacted, and it became a rare sight to see anyone in a store or other indoor public space without a mask (at least in the Phoenix area).  As you can see from the graph, a couple weeks after this change the positi...

I've been doing this blog for just about a year now. The first regular post was January 6, 2021. I'll reflect on that in a few days. Meanwhile, what kind of a media outlet would this be if I didn't do a year-in-review post? Looking back over the year's posts, it's amazing how much has been going on, and how much there potentially is to review. I can't spend all day on a detailed summary.  So I will try to focus on a bird's eye view. Vaccines & Anti-Vaxxers Vaccines have to be the biggest topic on this blog over the past year. Vaccines were very hard to get this time last year. A lot of people wanted them and the distribution was just getting started.  People had to navigate really crappy systems, like one in Arizona , to make reservations. There were " vaccine tourists " who would travel from other states and even countries in an effort to get jabbed.   Then, around March last year, those who wanted the shots had largely gotten them, and incre...

  As regular readers know, there has been quite a bit of coverage on this blog about mask effectiveness. It forced me to learn about aerosols and how they move around a room and spread the virus. On of the casualties of that learning has been my innocence/naivete regarding how much exhaust from other humans I probably have always breathed in. This new study demonstrates how even normal breathing creates a "saliva plume" that travels some distance from the breather.   The study concludes that "normal breathing indoors without a mask can transport saliva droplets capable of carrying virus particles to a distance of 2.2 meters, or 7.2 feet, in a matter of 90 seconds." Eeww.  That means if you're sitting next to someone who is not masked on a plane, or within seven feet of someone at a bar or restaurant, and they are merely breathing, you're going to be inhaling stuff from their "saliva plume." If that plume happens to include enough SARS-CoV-2 parti...

  We've all gotten familiar with masks and their limitations over the past year. There is no doubt that they work  (at least if they're not fake ), but they have problems. Leakage is one that can currently only be addressed with external appliances . Another is comfort.  Since masks are a big market, lots of people are trying to design a better virus-trap. Predictably, there are high-tech entries.  Razer is designing one , but it's not for sale yet. One that is for sale, assuming you have $299 to drop on a mask, is the Xupermask . It is a collaboration between Will.i.am and Honeywell (?). Both of these things have N95 filtration, active ventilation, speakers, and Bluetooth. The Xupermask has noise cancelling headphones too, for some reason.  They also look like they'd be at home in a Mad Max movie (assuming the post-apocalyptic landscape still has power to charge the masks).  While these entries are a little over-the top, they are at least designed to...

  [Hey...been off for a couple days due to work demands. I had a choice of what to post about today, but I'd be remiss if I didn't cover this particular topic.] Yesterday the Arizona governor dropped another Ducey, signing an order prohibiting universities from mandating vaccines or masks. You can't require people to be vaccinated, and you can't require those that aren't (or can't be) to wear masks to prevent them from catching or spreading disease.  This is—straight up—an order to promote public illness. It's like when Ducey decided in spring 2020 to ban local government mask mandates, only to change his mind when Arizona became the worst place in the world for COVID-19. If we needed masks to prevent illness then, why are they bad now? Of course, Ducey says this is all about individual freedom. But it's not just about individuals. If you don't get vaccinated and also don't wear a mask, you are endangering not only yourself but others around yo...

  As noted in an earlier post , right now it's the wild west out there when it comes to masks. It seems they are hyped based on everything except how well they work filtering virus-size particles.   Now, the  American Society for Testing and Materials (ASTM) has come to the rescue with a new set of standards for "barrier face coverings," known to most of us commoners as masks. If you follow that link you will be required—for reasons unclear to me—to go through a registration process that includes providing your address and phone number and verifying your email before you can see the standards.  I registered and got the document so you don't have to. There are basically three important parts to the standard, requirements for design, testing, and labeling.  Design Requirements Masks must cover the nose and mouth.  They can't have valves or other things that allow unfiltered breath to escape. They have to say if they're one-size-fits-all or sized for d...

This week the big trend in pandemic talk is "double masking." This is the practice of putting one mask on top of another to do a better job of filtering out virus aerosols.  Amanda Gorman did it at the inauguration , and we shouldn't underestimate the role of fashion here. Here is a chart based on Google Trends over the past 20 days, showing how the phrase has been picking up: The line really began to tick-up on the 25th, when Dr. Anthony Fauci endorsed the idea of double-masking by  saying   If you have a physical covering with one layer, you put another layer on, it just makes common sense that it likely would be more effective, and that's the reason why you see people either double masking or doing a version of an N95 . Experts agree that a very important aspect of mask effectiveness is how well it fits. Masks that don't fit properly allow leakage of unfiltered air when inhaling and exhaling.  A leaky mask won't work well regardless of what material it...