Kevin Drum has what to my eye is a pretty good post on the relative effectiveness of different mask types in preventing COVID-19. The types he considers are:
- fabric 2-layer
- fabric 3-layer
- surgical
- N95 non-fitted
- N95 fitted
If you’re wearing a surgical mask and everyone else is wearing cloth masks, it provides about 3x the protection of doing nothing.
Just generally, I’d beware of the N95 numbers. You should probably assume that even if you’re being careful, your spiffy N95 mask isn’t all that well fitted. The “N95 non-fitted” line is probably the most accurate for real life.
This is the best I could come up with doing a non-expert review of the literature. Don’t take it as gospel, but as a rough estimate. If better data comes my way, I’ll let you know.
I really wish the experts were doing this sort of explanation and analysis rather than relying on laymen to do it for them. I wonder about how much of these are a priori assumptions and how much are measured results. Note, too, the discrepancy in Koh which shows no benefit between wearing fabric 2-layer masks and N95 non-fitted masks. I also wonder about some of the qualitative assumptions built into analyses of this sort but at least it’s a start.
Ok, let’s run the numbers. First size of mask holes, https://www.nist.gov/feature-stories/masks-under-microscope . The one image shows holes about 25 microns. Web seems to say Covid virus is 20 or perhaps 200 nanometers in diameter. There are 1,000 nanometers in one micron. Soooooo,………exactly how do those holes stop a Covid virus? Right, I heard that they cling to really big water droplets,……right, how long before a droplet so small you can’t see it evaporates? (Handy converter https://www.calculator.net/conversion-calculator.html)
Abe: There are 1,000 nanometers in one micron. Soooooo,………exactly how do those holes stop a Covid virus?
Because the virus is transmitted, not as single viruses, but through droplets and aerosols. Furthermore, it takes a minimal number of viruses to cause an infection. Even a cloth mask and social distancing will stop most droplets spread by coughing.
However, unlike droplets, aerosols remain in the air for a significant amount of time. In a poorly ventilated space, especially one with large numbers of people, aerosols essentially pollute the air with contagion.
But, most aerosols contain few or no viruses. So, reducing the amount of aerosols, even if it doesn’t eliminate them, can reduce the probability of infection significantly by limiting viral load. See Cheng et al., Face masks effectively limit the probability of SARS-CoV-2 transmission, Science 2021.
“You should probably assume that even if you’re being careful, your spiffy N95 mask isn’t all that well fitted. The “N95 non-fitted†line is probably the most accurate for real life.”
And that’s probably an absolute best case. You won’t get but a fraction of the required compliance. Those kids wearing masks in the classroom? Seriously? The entire classroom day would be taken up policing masks.
From day 1 this has all been a farce. Essential workers, anyone? Out and about…….and amongst us. Today, eateries, ahem, political gatherings, bars, ill fitted masks…………
And now, with masks and vaccines quite prevalent we have omicron tearing through the population at warp speed. I realize for many masking is done with good intentions, but it doesn’t change the fact that its largely a fools errand.
Also those holes don’t tend to go straight through the entire thickness of the mask. The viruses would not always move in a straight line through those tunnels. At that scale Brownian motion will affect movement.
There is also an interesting pre print out that looks at the viability of viruses in aerosols. Before this study people looked only at whether you could detect the virus. This study looked at the virus being viable and able to infect someone. In their study the more finely aerosolized virus was viable for a very short time. That suggests are major concern should be with droplets and the larger clumps, which is what masks are especially good at catching.
Steve
Yesterday Senator Ron Johnson convened a 5-hour round table discussion regarding an overview of the global response to COVID. The group consisted of highly credentialed physicians and experienced nurses giving their on-the-ground, worldly experiences, studying and dealing directly with COVID. When they touched on masks, the consensus was that cloth and surgical masks were useless. Even wearing the N95 mask was considered only â€slightly better.†The P100 mask, although untested for COVID, was said to give good one-way protection only for the mask wearer.
Dr. Richard Urso chimed in saying there were no randomized studies showing the overall value of wearing masks to stop the spread of this virus. A common example cited, demonstrating the benign repercussions of not following all the protocols demanded here – social distancing, quarantines, universal mask mandates – is how 1.9 million Swedish children did not interrupt their education, mask-up or practice social distancing and had no deaths by pursuing this path of normalcy and common sense. DANMASK-19 was also mentioned, as a singular study indicating “all mitigating measures taken in Denmark had no tangible effect on the spread of COVID-19, including a universal mask mandate.â€
Also, so many “experts†seem numb to the enormous collateral damage going on all around us, obsessing only on the seesaw wave of virus case numbers being constantly reported by the media and public health agencies. Consequently, the ill effects of constantly wearing masks seems irrelevant. The headaches, face rashes, pulmonary infections, teeth problems are brushed aside. The stunted social growth experienced in young children, from not being able to pick up facial cues hidden by masking. Even the drop in IQ in babies, the increased “cutting†noted in girls, suicides, drug over doses, all interwoven into our inhumane, elongated extensions of separating humans from humans because of a virus with an IFR, in most cases, of less than 1%.
BTW, I highly recommend for those of you wishing to submerse yourself, in a substantially more informative discussion about COVID, to find the link to Johnson’s Second Opinion Forum. It transcends what we’ve all been indoctrinated to understand, being harangued by media, government, medical administrations, 24/7, to willingly become a prisoner to a virus far more treatable and less virulent than we’ve been led to believe.
Sweden paid the price by having covid deaths about an order of magnitude higher than their neighbors. Like so many things it is all about the trade offs. Also, as most wont know or acknowledge, Sweden did hold older kids out of school. I think the cutoff was age 14.
“And now, with masks and vaccines quite prevalent we have omicron tearing through the population at warp speed.”
But the ones getting hospitalized and dying (and presumably not wearing masks) are largely the unvaccinated. Again, it is trade offs. After the first couple of months when we were much worse at treating covid deaths and hospitalizations have been dominated by states that have fewer mitigation efforts and fewer people vaccinated.
Steve
Sweden stayed open and did not nuke their economy, citizens’ mental health, and children’s access to education by implementing extreme protocols, like the U.S. has done. The results has been the U.S. 2676 deaths/1 million to Sweden’s 1535 deaths/ 1 million. Belgium had 2525 deaths for the same metric, while the Netherlands was a bit under Sweden with a number of 1235.
Basically, Sweden bore the burden of heavy criticism and rebuke for going against the grain of global lockdowns, and now is looked at as having one of the most sensible responses to the overwrought direction COVID was taken by so many countries, including our’s.
â€But the ones getting hospitalized and dying (and presumably not wearing masks) are largely the unvaccinatedâ€.
That statement is totally false – misinformation at it’s finest – brought to you by corrupted data being spread around this country. Vaccinated patients in the hospital are often simply listed as “unknown,†so as not to mire the data down in numbers that would create more vaccine hesitancy. Other countries are far more honest, such as the U.K. and Israel who honestly state hospitalization data where numbers often show the majority have been fully vaccinated. I think it’s something like 45 states who have no masking requirements. And, here in CA, where we will never be free of masking, cities like San Francisco and LA have had an explosion of Omicron cases, with masking requirements fully in place. Plus, SF is a highly vaccinated place in the country, as well as tightly controlling the unvaccinated from going anywhere.
Fact: these “vaccines†do not protect anyone from getting COVID, nor do they prevent anyone from spreading it to others. Their efficacy, of buffering more extreme symptoms, is short-lived, waning sometimes within months. The latest variant, Omicron, has mutated so much that it appears to be resistant to any help the vaccine may give a person, which is why there are so many “break-through†cases baffling the medical establishment. The unsafe aspects of these vaccines continue to be ignored, despite evidence mounting regarding huge numbers of the fully vaccinated reporting episodes of abuse after being jabbed. Finally, those who refuse to acknowledge how unsafe and ineffective these vaccines really are seem to be in perpetual denial – similar to the “see no evil, hear no evil, say no evil†state of mind.
“But the ones getting hospitalized and dying (and presumably not wearing masks) are largely the unvaccinated.”
You are playing fast and loose with the not wearing masks comment, steve. And this is exactly how trust has been lost in the health care profession. But I have no issue with the unvaccinated comment. It seems undeniable that vaccination reduces hospitalizations and deaths. The issue then turns on personal choice.
Separately, a conversation with my daughter just this evening (she is very frustrated) is revealing. She again points out that compliance among grade schoolers is simply an absurd notion (as in I dare you to keep a mask on them for 5 minutes), but also points out that because of mandates teachers are spending a large portion of the school day attempting to enforce mandated masking – with minimal effect. That is, they are not teaching; the kids are falling further and further behind.
Do what you want with the 60+ crowd, the obese, the diabetic and a handful of other co-morbidities. But the kids? Its not tradeoffs in any practical sense. Its political and immoral.
This is my favorite headline showing how Sweden compared with its neighbors.
https://www.businessinsider.com/coronavirus-sweden-gdp-falls-8pc-in-q2-worse-nordic-neighbors-2020-8
If you continue to follow GDP you dont see that Sweden is better than its neighbors. Most people would try to choose for comparison countries which are geographically, climatically, size and sociologically similar, ie neighbors. That would not be there US or Belgium. As I said death rates are almost an order of magnitude higher in Sweden.
“That statement is totally false”
It is true everywhere. When you get into areas where there are very high rates of vaccination you can see the total number of people admitted tilt towards the vaccinated but the rate of admissions will still be much higher for the vaccinated. This is just a math thing. Pretty sure Drew can explain it if you ask. Engineers are supposed to take math.
Drew- I am wrong? The norm is that people who refuse to get vaccinated commonly wear masks? I did caveat that but I think it is a very reasonable assumption. Hard to find good data but if I am reading this right only 37% of unvaccinated wear masks.
https://www.kff.org/coronavirus-covid-19/poll-finding/kff-covid-19-vaccine-monitor-july-2021/
I think some schools are having kids wear masks when not needed. I would prefer that be a decision made by local schools or school systems based upon local conditions and values. Whatever they decide it should probably acknowledge that the risks of a 24 y/o teacher are different than those of a 64 y/o or even 54 y/o.
In my old age I have preferentially dome some more work with kids. Problem kids usually mean problem parents. With good parents it isn’t that hard to keep mask on for 5 minutes or even 30. I am guessing that for a whole day, and day after day, it would get hard. I do feel sorry for the teachers. I think most of them try hard to teach.
” It seems undeniable that vaccination reduces hospitalizations and deaths.”
You do realize that puts you in a minority or small majority within your party. jan is more the norm, especially among those who are politically active. This belief that there is a worldwide conspiracy going on and only a tiny group of people have the special knowledge that everyone else is wrong.
Steve
Jan: Other countries are far more honest, such as the U.K. and Israel who honestly state hospitalization data where numbers often show the majority have been fully vaccinated.
“The age-standardised mortality rate (ASMR) for deaths involving COVID-19 was 96% lower for people who received the second dose at least 21 days ago compared to unvaccinated people between 1 January and 31 October”
https://www.ons.gov.uk/peoplepopulationandcommunity/birthsdeathsandmarriages/deaths/bulletins/deathsinvolvingcovid19byvaccinationstatusengland/deathsoccurringbetween1januaryand31october2021
“Overall in Israel, according to Health Ministry data, only 14 percent of Israelis over 20 are unvaccinated, yet they account for 45 percent of serious COVID cases.”
https://www.haaretz.com/israel-news/israel-covid-omicron-unvaccinated-14-adults-100-ecmo-serious-cases-1.10530817
Steve, that Business Insider article you posted was dated August 2020, when everything was going sideways, and hardly relevant for today’s status, January 2022.