Lunchtime pandemic reading.
Standard disclaimer: this is a roundup of informative pieces I've read that interest me on the severity of the crisis and how to manage it. I am not a qualified medical expert in ANY sense; at best I am reasonably well-read laity. ALWAYS prioritize advice from qualified healthcare experts over some person on Facebook.
This is also available as an email newsletter at https://lunchtimepandemic.substack.com if you prefer the update in your inbox.
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It's all about the fit. "During January 2021, CDC conducted various experiments to assess two methods to improve medical procedure mask performance by improving fit and, in turn, filtration: 1) double masking and 2) knotting and tucking the medical procedure mask (Figure 1). The first experiment assessed how effectively various mask combinations reduced the amount of particles emitted during a cough (i.e., source control) in terms of collection efficiency. A pliable elastomeric headform was used to simulate a person coughing by producing aerosols from a mouthpiece (0.1–7 μm potassium chloride particles) (7). The effectiveness of the following mask configurations to block these aerosols was assessed: a three-ply medical procedure mask alone, a three-ply cloth cotton mask alone, and the three-ply cloth mask covering the three-ply medical procedure mask (double masking). The second experiment assessed how effectively the two modifications to medical procedure masks reduced exposure to aerosols emitted during a period of breathing. Ten mask combinations, using various configurations of no mask, double masks, and unknotted or knotted and tucked medical procedure masks, were assessed (e.g., source with no mask and receiver with double mask or source with double mask and receiver with no mask). A knotted and tucked medical procedure mask is created by bringing together the corners and ear loops on each side, knotting the ears loops together where they attach to the mask, and then tucking in and flattening the resulting extra mask material to minimize the side gaps†† (Figure 1). A modified simulator with two pliable elastomeric headforms (a source and a receiver) was used to simulate the receiver’s exposure to aerosols produced by the source (8). In a chamber approximately 10 ft (3.1 m) long by 10 ft wide by 7 ft (2.1 m) high, which simulated quiet breathing during moderate work, the source headform was programmed to generate the aerosol from its mouthpiece at 15 L/min (International Organization for Standardization [ISO] standard for a female performing light work), and the receiver headform’s minute ventilation was set at 27 L/min (ISO average of a male or female engaged in moderate work).§§ For each of the 10 masking configurations, three 15-minute runs were completed.
Results from the first experiment demonstrated that the unknotted medical procedure mask alone blocked 42.0% of the particles from a simulated cough (standard deviation [SD] = 6.70), and the cloth mask alone blocked 44.3% (SD = 14.0). The combination of the cloth mask covering the medical procedure mask (double mask) blocked 92.5% of the cough particles (SD = 1.9).
In the second experiment, adding a cloth mask over the source headform’s medical procedure mask or knotting and tucking the medical procedure mask reduced the cumulative exposure of the unmasked receiver by 82.2% (SD = 0.16) and 62.9% (SD = 0.08), respectively (Figure 2). When the source was unmasked and the receiver was fitted with the double mask or the knotted and tucked medical procedure mask, the receiver’s cumulative exposure was reduced by 83.0% (SD = 0.15) and 64.5% (SD = 0.03), respectively. When the source and receiver were both fitted with double masks or knotted and tucked masks, the cumulative exposure of the receiver was reduced 96.4% (SD = 0.02) and 95.9% (SD = 0.02), respectively.
These laboratory-based experiments highlight the importance of good fit to maximize overall mask performance. Medical procedure masks are intended to provide source control (e.g., maintain the sterility of a surgical field) and to block splashes. The extent to which they reduce exhalation and inhalation of particles in the aerosol size range varies substantially, in part because air can leak around their edges, especially through the side gaps (9). The reduction in simulated inhalational exposure observed for the medical procedure mask in this report was lower than reductions reported in studies of other medical procedure masks that were assessed under similar experimental conditions, likely because of substantial air leakage around the edges of the mask used here (10). In another study, adding mask fitters to two medical procedure masks, which produced different reductions in exposure when unmodified, enhanced their efficiencies to the same equally high levels (2). This observation suggests that modifications to improve fit might result in equivalent improvements, regardless of the masks’ baseline filtration efficiencies."
Source: https://www.cdc.gov/mmwr/volumes/70/wr/mm7007e1.htm
Commentary: These numbers are why I advocate so strongly for people to upgrade to things like P100 respirators. When you've got just a cloth mask on and you're around someone who has their mask on improperly (meaning diminished source control), double masking reduces exposure by 83%; compare that to a P100's performance at reducing particles by 99.97%.
As of this morning, many P100 respirators were still available on Amazon. You could go absolutely, unnecessarily overboard and get a powered welding respirator if you're really, really, REALLY concerned, but that's overkill unless you're hanging out in a COVID ward on a regular basis. (if you do, make sure it's a welding one so you're not taking away gear from healthcare workers)
That said, NO mask works as intended if it's on wrong. If you wear glasses and they're fogging up? Your mask isn't working correctly - it's letting out air in a direction that it shouldn't be going. Feel a nice cool breeze from the sides of your mask? It's on wrong. Air should be going THROUGH the material, rather than around it.
How do you know it's on right? No cool spots from air flowing around it. And frankly, it's tight. When you look at photos of healthcare workers after a shift, their faces are bruised because the masks are on TIGHT. No air is flowing around the sides of the mask, only through it.
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Keeping all the strains straight. "As an infected cell builds new coronaviruses, it occasionally makes tiny copying errors called mutations. Scientists can track mutations as they are passed down through a lineage, which is a branch of the viral family tree.
A group of coronaviruses that share the same inherited set of distinctive mutations is called a variant. If enough mutations accumulate in a lineage, the viruses may evolve clear-cut differences in how they function. These lineages come to be known as strains. Covid-19 is caused by a coronavirus strain known as SARS-CoV-2.
Over the course of the pandemic, a number of variants of SARS-CoV-2 have arisen. Some of them are raising worries that they may draw out the pandemic or make vaccines less effective.
Variants of concern
Lineage Variant name Status
B.1.1.7 Variant of Concern 202012/01, or 501Y.V1 Emerged in Britain in December and is roughly 50 percent more infectious. Now detected in over 70 countries and 33 states.
B.1.351 501Y.V2 Emerged in South Africa in December. Reduces the effectiveness of some vaccines.
P.1 501Y.V3 Emerged in Brazil in late 2020. Has mutations similar to B.1.351.
B.1.427, B.1.429 CAL.20C Carries the L452R mutation. Common in California, but not yet shown to be more infectious."
Source: https://www.nytimes.com/interactive/2021/health/coronavirus-variant-tracker.html
Commentary: Knowing what strain is spreading in your area is important, because some strains - B.1.1.7 in particular - is much more infectious and therefore a higher risk, meaning your masking protocols should be even more rigorous.
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What about a vaccine glut? "My @WSJ Op Ed: We must plan now for when Covid vaccine supply exceeds demand; and how we create incentives. It starts with setting up framework for making a decision on when we can scale back masks and distancing once sufficient vaccination is reached.
More people will seek vaccines if it means they can resume more of their normal life. But lacking definitive data on transmission, we aren't telling people when that will be, or even setting up a transparent process for evaluating the questions and making the recommendations.
Right now, with dense epidemic and uncertainty on scope of infection and transmission with vaccination, we tell public to stay masked after vaccination. At some level of vaccine uptake and declining prevalence; that guidance will change. We need a framework for that decision.
After early challenges, vaccine delivery is keeping up with supply. But by the end of March, the monthly vaccine supply may reach 100 million doses. To keep pace, the vaccination rate would have to double and then some. This will require an all-of-the-above approach to administering vaccines, tapping substantial capacity in pharmacies, primary-care practices and other trusted health-care providers.
Especially with improved delivery, at some point, perhaps in April, supply will start exceeding demand. The challenge won’t be how to ration a scarce resource, but how to reach patients reluctant to get vaccinated. Based on the latest Kaiser Family Foundation tracking surveys, more than half of Americans say they don’t want to get vaccinated. Some may simply want to wait; others may be set against getting it.
One reason for the hesitancy may be that it was necessary to ration scarce doses at the start, causing many Americans to internalize the idea that some people may be more likely to benefit or more deserving than others. It is essential to emphasize in public-health messaging that every adult can benefit and deserves the protections they can provide, and there will be no reason to forgo it once the scarcity problem is solved."
Source:
Source: https://www.wsj.com/articles/what-to-do-when-theres-a-covid-19-vaccine-glut-11612732696
Commentary: I suspect we'll hit that point sooner rather than later. The good news is for people like you and me, we'll get access to the vaccine sooner than we think. The bad news is that with so much hesitancy, the virus will still have fertile grounds to spread and mutate, causing ongoing challenges with keeping vaccines current.
What's the answer? To the extent possible, cooperation with the private sector - ESPECIALLY insurance companies - to encourage vaccination. For example, insurers could say to businesses that your rates will go up unless X percent of your employees are vaccinated. Venues like bars and restaurants could mandate vaccination as a condition for entrance, without which insurers will revoke or increase event insurance pricing. Health insurance companies can offer discounts on premiums and deductibles to people who get vaccinated.
Private businesses can do their part as well. Bars and restaurants can offer vaccine specials - show your vaccination card and get a free appetizer or something. Stores can offer discounts or conversely, raise pricing for the non-vaccinated as a service fee for covering the costs of cleaning and sanitization.
Governments can offer tax incentives - get vaccinated and registered with the IRS, knock another $50 off your tax return. On government-administered services like airlines, vaccination can be made mandatory for use.
As always, it comes down to incentives. If government and the private sector cooperate and offer juicy enough incentives, all but the most reluctant people will participate.
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A reminder of the simple daily habits we should all be taking.
1. Always wear the best mask available to you when out of your home and you'll be around other people. Respirators are back in stock at online retailers, too. Wear an N95/FFP2/KN95 or better mask if you can obtain it.
2. Get vaccinated as soon as you're able to.
3. Wash/sanitize your hands every time you are in or out of your home for any reason.
4. Stay home as much as possible. Minimize your contact with others and maintain physical distance of at LEAST 6 feet / 2 meters, preferably more. Avoid indoor places as much as you can; indoor spaces spread the disease through aerosols and distance is less effective at mitigating your risks.
5. Get your personal finances in order now. Cut all unnecessary costs.
6. Replenish your supplies as you use them. Avoid reducing your stores to pre-pandemic levels in case an outbreak causes unexpected supply chain disruptions.
7. Ventilate your home as frequently as weather and circumstances permit, except when you share close airspaces with other residences (like a window less than a meter away from a neighboring window).
8. How to properly fit a mask:
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Common misinformation debunked!
There is no mercury or other heavy metals in the Pfizer mRNA vaccine. https://www.technologyreview.com/2020/12/09/1013538/what-are-the-ingredients-of-pfizers-covid-19-vaccine/
There is no genomic evidence at all that COVID-19 arrived before 2020 in the United States and therefore no hidden herd immunity:
Source:
There is no evidence SARS-CoV-2 was engineered, nor that it escaped a lab somewhere.
Source: https://www.washingtonpost.com/world/2020/01/29/experts-debunk-fringe-theory-linking-chinas-coronavirus-weapons-research/
Source: https://www.nature.com/articles/s41591-020-0820-9
Source: https://www.nationalgeographic.com/science/2020/05/anthony-fauci-no-scientific-evidence-the-coronavirus-was-made-in-a-chinese-lab-cvd/
There is no evidence a flu shot increases your COVID-19 risk.
Source: https://www.factcheck.org/2020/04/no-evidence-that-flu-shot-increases-risk-of-covid-19/
Source: https://academic.oup.com/cid/advance-article/doi/10.1093/cid/ciaa626/5842161
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A common request I'm asked is who I follow. Here's a public Twitter list of many of the sources I read.
https://twitter.com/i/lists/1260956929205112834
This list is biased by design. It is limited to authors who predominantly post in the English language. It is heavily biased towards individual researchers and away from institutions. It is biased towards those who publish or share research, data, papers, etc. I have made an attempt to follow researchers from different countries, and also to make the list reasonably gender-balanced, because multiple, diverse perspectives on research data are essential.
This is also available as an email newsletter at https://lunchtimepandemic.substack.com if you prefer the update in your inbox.