Skip to content

Here’s a quick look at the evidence about mask wearing

How useful are face masks in halting the transmission of COVID-19? There are two things to look at.

First, how well do they protect the wearer? Here are the results of a literature review done last year:

These are not super great results, and the authors warn that most of the studies were underpowered and had large error bars. N95 masks did a better job than the others, but most likely masks in general do little to protect wearers.

More important is how well masks prevent transmission of COVID within a community. I couldn't find any recent literature reviews that address this, but an informal review in JAMA earlier this year listed eleven studies of mask wearing on community spread of COVID:

This article presents no overall estimate of how well mask-wearing works to slow the spread of COVID, nor does it estimate how good each of these individual studies is. That said, an eyeball review of the results suggests that masks are effective at slowing the transmission of COVID if they're widely used.

The CDC keeps track of mask studies on its website here. Their list is more current than the JAMA list, and virtually all studies continue to show that masks are effective at slowing the spread of COVID:

At least ten studies have confirmed the benefit of universal masking in community level analyses: in a unified hospital system, a German city, two U.S. states, a panel of 15 U.S. states and Washington, D.C., as well as both Canada and the U.S. nationally....Two of these studies and an additional analysis of data from 200 countries that included the U.S. also demonstrated reductions in mortality. Another 10-site study showed reductions in hospitalization growth rates following mask mandate implementation. A separate series of cross-sectional surveys in the U.S. suggested that a 10% increase in self-reported mask wearing tripled the likelihood of stopping community transmission.

But what type of mask works best? Good studies on this are hard to find, but in general N95 masks are best, surgical masks are good, and cloth masks are lousy. You should especially use N95 masks if you're going to be in close proximity to others for long periods, for example on a long airplane trip or an all-day meeting in a stuffy room.

Based on all this evidence, my view is that masking up indoors isn't a game changer like vaccines, but it's a pretty good countermeasure that easily wins a cost-benefit analysis. So why not do it?

74 thoughts on “Here’s a quick look at the evidence about mask wearing

  1. educationrealist

    "So why not do it?"

    Because they're horrible? They're not easy, they make it hard to breathe and to understand others. Because when you spend all day with people masked it's depressing. Because if you have to talk all day, you end up permanently hoarse.

    All for a reduction that isn't anything to get excited about.

    There are a thousand other illnesses that we could see a reduction in if we were forced to wear masks all the time. We haven't ever bothered before, and it's obscene we're doing it now. Even worse, the people most likely to be masked all day are below the age of 18.

    But hey, who cares? They're just kids. So long as pundits can sit at home all day and do their job just like always and only wear a mask a few minutes a day, who cares what happens to the people who are public facing all day?

    1. jv

      Are any of those thousand other illnesses averaging 400k dead Americans a year? Because if so... Maybe we should start wearing masks for them?

      1. Vog46

        "If you have trouble breathing then you have other issues not related to the mask."

        And you would be EXEMPTED from wearing one by a medical professional.
        At work it's a different story. If you know you are going to be exposed to a chemical vapor that is injurious you are required to wear a mask, or respirator. You cannot be exempted by a medical condition, it's a part of the job. You get tested for your ability to wear one.

        Filtration is hard. Aerosol filtration is very hard and people with impaired lung function just cannot breathe through many of the better masks.
        I have seen people in stores doing these things:
        Pulling mask off their face to talk
        Wearing the mask below the nose
        Being bearded while wearing the mask
        Heck I saw one woman riding a handicapped cart with a nasal cannula attached to her portable O2 generator wearing a mask over the tubes.

        While I applaud the effort I just shake my head sometimes.........

    2. Joel

      Surgeons and nurses wear have been wearing masks, sometimes for hours at a time, for decades. But hey, who cares? They're just protecting the lives of their patients. So long as whiners like you can sit at home all day and troll comment threads just like always and only wear a mask a few minutes a day, who cares what happens to the people who are public facing all day?

      Grow up.

    3. doughelo

      Absolutely agree. I'd like to see a study of how much masks slow transmission between vaccinated people. Since that's pretty rare, I suspect not much. I just went into a museum in California where you have to be vaxxed to enter, yet you also have to wear a mask. Why? They're only protecting the unvaxxed, who made their choice long ago. Why should I help them out if they're the ones that voluntarily breed these variants? Maybe to spare the health care workers, but otherwise, screw 'em.

      1. Joel

        "Why should I help them out if they're the ones that voluntarily breed these variants?"

        • to keep hospital beds open for accident victims and cancer patients;
        • to reduce transmission and thus the chance of a new variant appearing that could evade vaccines;
        • to protect those who are unvaxxed for valid medical reasons.

        Grow up and stop being selfish.

    4. jte21

      Over the past two years the *only* people I've heard complain about masks are cranky adults. With the exception of those with disabilities/special needs, kids have absolutely no problem masking up. And in our district, where everyone during class has to be masked (and teachers/staff have to be vaccinated) there's been virtually no transmission in the school.

  2. jharp

    I wear the KN95’s and make sure they are tightly fitted.

    And it really doesn’t bother me much at all.

    And I didn’t catch Covid.

    That, and I haven’t had so much as a sniffle in two years.

    I don’t see not wearing a mask among the public in my near future.

    1. Salamander

      Same here! I've always hated getting colds, because they hung on for so many weeks. These last few (masked) years, cold-free, have been amazing! I like it.

      Now, if only the masks were effective on seasonal pollen... One would think they'd have to be, given how humongous pollen is compared to viri.

      1. HokieAnnie

        Seasonal pollen - yes but once you step inside and take off the mask you are dealing with all the indoor allergens. There's just no escape for me except maybe walking outside on a winter day after the leaves have been raked up.

  3. James B. Shearer

    "... So why not do it?"

    Because apparently most people are wearing ineffective cloth masks because they haven't been told otherwise. And your article unhelpfully doesn't even discuss KN95 masks which are what is actually available.

    1. Mitch Guthman

      Just to be clear. Even a cloth mask is effective at protecting others. I have always accepted that my mask affords me very little protection and probably next to none since I’m fully vaccinated.

    2. iamr4man

      I believe N95s would be grouped in with KN95s and KF94s.
      N95s are currently pretty available. My favorite, the 3M N95 Aura is available on Amazon. They have proven really good for me in that I wear glasses and they don’t fog up.

      1. James B. Shearer

        "...N95s are currently pretty available. My favorite, the 3M N95 Aura is available on Amazon. .."

        Currently $21.47 for a 10-pack on Amazon and you might get it in 4 weeks. Compare to $3.00 a 10-pack at my local supermarket for KN95.

        1. iamr4man

          I’ve tried numerous KN95s with no luck getting them to fit on my face without my glasses fogging up. Since I’ve started using the 3Ms I’ve noted a lot people recommending them so it’s not surprising they are getting harder to get. Makes me glad I stocked up. But note that if you buy the box of 20 it comes by the 10th of January and they are a bit cheaper each.
          Also note that there has been a lot of counterfeiting in the KN95 market. Definitely get what works for you but also do your best to avoid counterfeits.

          1. James B. Shearer

            "Also note that there has been a lot of counterfeiting in the KN95 market. Definitely get what works for you but also do your best to avoid counterfeits."

            I don't particularly care if they are counterfeit as long as they work (and aren't otherwise dangerous). So is there an actual problem? And if there is how exactly am I supposed to tell the good masks from the bad masks?

      2. Salamander

        In my experience and I do respirator fit testing, KN-95s are in no way comparable with N-95s. But they're a shade better than a surgical mask. However, even a KN-95 plus a surgical mask is not as good as a fit-tested N-95 on somebody who knows how to put them on properly.

        1. Vog46

          "However, even a KN-95 plus a surgical mask is not as good as a fit-tested N-95 on somebody who knows how to put them on properly."

          Yup.

        2. James B. Shearer

          "... KN-95s are in no way comparable with N-95s. .."

          How about versus cloth masks the actual alternative in many cases?

          1. Salamander

            I've never bothered to test with just a cloth mask. It seemed pointless. On the other hand, they seem to work just fine for the General Public, and I've worn one myself, until we managed to pick up a box of KNs. The KNs fit a little tighter, and don't fog my glasses quite as much.

    3. jte21

      One person wearing a cloth mask is probably not very useful. If everyone's wearing a cloth mask, it's effectively like doubling up. Not perfect, but I wager pretty good in casual public settings like the post office, supermarket, or a classroom.

  4. WryCooder

    Man Oh Man I want to be wedded to evidence-based decsion-making.

    My understanding is that the spread of COVID is primarily due to aersols (air-based) which means that there would be two effective counter-measures: 1) masking and 2) proper ventilation of indoor spaces.

    It really sucks that a) NONE of the funds expended to fight COVID have focused on indoor air quality OR that every business, school, home doesnt have a CORSI fan (https://cleanaircrew.org/boxfanfilterfaq/)

    and b). that N95s aren't freely issued at no-cost to all.

    Personally, I expect that masking will be my default even after (if) Covid is under control. Flu used to spread unabated through my place of work (I expect the carrier was my boss who would come to work no matter how sick) but it's a nil-factor thanks to mask mandates.

    1. jte21

      It really sucks that a) NONE of the funds expended to fight COVID have focused on indoor air quality OR that every business, school, home doesnt have a CORSI fan (https://cleanaircrew.org/boxfanfilterfaq/)

      That's actually not the case. All the federal Covid relief packages have included billions for grants to schools for upgrading HVAC and indoor air quality. Now, districts have to apply for the money and then bid out the contracts and all that, but technically, it's there if they need it.

  5. Citizen99

    I thought we went through this topic a year ago. Please stop it with disparaging cloth masks!
    As a chemical engineer familiar with all kind of filtration, I can guarantee that even a single layer of cloth is vastly better than nothing, and two layers of finely woven cloth is far better than one layer. Labeling cloth masks as "lousy" will give many people the impression that a cloth mask is useless, an attitude which could cause people to die.
    Far more important that the material used in a mask is HOW it is worn. I see many people wearing their masks below their noses, which is as dumb as it gets. I see many more wearing a mask that is barely perched on their noses, with a big gap between cheek and mask. That's almost as dumb. I wear a two-layer cloth mask and use a length of paper tape (available at pharmacies) to seal the gap between mask and cheek below my eyes. I do this primarily to prevent fogging my glasses, but it ensures that my breath goes THROUGH the mask and not through an open gap around the edges. I don't have experimental data, but common sense tells me that this is FAR more protective than a surgical mask worn with open gaps big enough for a mouse to run through.
    So please stop with the "lousy" label for cloth masks; that just give anti-maskers an excuse to eschew the mask altogether.

    1. James B. Shearer

      "So please stop with the "lousy" label for cloth masks; that just give anti-maskers an excuse to eschew the mask altogether."

      If KN95's are far better people should be informed of this.

      1. golack

        'Education is good. But the different masks serve different purposes. Cloth masks can help protect others, but not yourself so much. Fitted N95's do a good job at protecting you, as well as protecting others (unless it is equipped with a vent).

  6. bebopman

    And then there’s the good possibility that masks “work” because people who wear them are also careful in many other ways.

  7. Pingback: A quick look at the evidence about mask wearing | Later On

  8. Pingback: Looking a little more deeply into VR headsets and workout programs | Later On

  9. xmabx

    I thought the point of masks was that they are good at protecting others if you are sick but poor at protecting you from sick people especially if they aren’t wearing a mask. Which is why masks need to be mandated to be effective.

  10. rational thought

    To citizen 99 and wrycooder,

    In my understanding, the fact that covid is so aerolizatized is a reason why masks, especially cloth masks, are largely ineffective and a reason why we should be less inclined to mask, not more. Viruses that spread more through droplets, like the flu, can be stopped more by masks, even cloth masks.

    A cloth mask is just going to about zero to stop aerosolized virus particles- they are just so small they can go right through. And even an n95 mask fully fitted cannot stop them all- they are still smaller than the pores. But more likely they will be caught and trapped somewhere then - basically like the virus needing to wind its way through a maze without hitting the walls. N95 gives less room. A cloth mask like a person going through a maze with passages 50 feet wide - too easy.

    But still, even though covid spreads a lot through aerosolization , more than the flu does, that does not mean that droplets are no threat . A droplet can spread covid too and maybe a large viral load. So even a cloth mask can help some at least a little.

    But our current policy is silly. A policy of not requiring masks at all as not useful enough to be worth the downside ( especially since so many wear them badly) is arguable. A policy requiring at least a surgical mask or better n95 is also arguable . A policy requiring masks but allowing cloth just makes no sense, at least since the early period when we did not know how aerosolized and had very limited supply for anything but cloth.

      1. pfbr2a

        I'm in England and we've had no trouble. But it looks like the US equivalent in N99, and the only one of those I'm seeing readily available is a 3M version with outlet valve (Amazon.) That protects you from them but not them from you, which is not ideal.
        However the ffp2 is not far behind, and that seems to be the same spec as N95. So, what the post says is your best bet.

    1. Salamander

      The FFP3 standard better than an N-95. FFP3 masks have, per the specs, "Aerosol filtration percentage: Not less than 99%." N95s have not less than 95% filtration, and are slightly better than an FFP2 (94%).

      It should be noted that you need to be aware there are lots of counterfeits, and how to distinguish them from the real article.

  11. Vog46

    We are looking at this in a "non-situational" manner.
    I will assume social distancing is still taking place.
    Outside in the air? No mask required. The dispersal of the aerosol even by the wind currents YOU cause by moving is enough to minimize the risk. Outdoor sports events? Again different situation. YOU are yelling and screaming with people at each elbow. Masks required along with vaccine passport upon entry
    Indoors at stores? You need them. The better the mask the better the protection will be for others and YOU. If you are moving about in that store the protection is better. IF you are in a Church the situation changes yet again as you are stationary for the most part as are others around you. Concert venues and indoor sports events? I wouldn't even hold them, never mind attempt to attend one - but masks required along with VP(vaccine passport).
    Indoors with family? Who's vaccine status you know? Who's health you know? I'd say mask-less is OK.
    But lets get the monkey out in the room here. What we are talking about are schools. Masks and vaccine mandates for all students and employees.
    Why?
    First - they haven't changed their air handling equipment all they are doing is cleaning the rooms AFTER the school day is over. This also goes for airplanes and cruise lines. I didn't see a big retro-fit of airplane and cruise line air handlers have you? No. In fact cruise lines are now in big business trouble, again as they started prepping for departures as our vaccine status ramped up. Omicron, because of it's breakthrough capabilities then changed the game in 30 days, and they got caught flat footed.
    Should schools be shut down? Maybe for a month. This will give us time to make sure all adults are boosted, and children get their initial round of vaccines.
    But all non essential travel has to be looked at - especially cruises. Ports of call are STOPPING ships from entering their harbors but we can't rely on THEM to make the hard decisions for us. And THAT is exactly what we are doing. Hawaii should shut down MOST of its hotels, bars and restaurants. For at least the next 30 days, maybe 60.
    A few republican governors shot themselves in the foot with the absurd decision to pay enhanced UI benefits to those who lose their jobs due to refusing the vaccine - completely ignoring their own arguments that enhanced UI makes people want to stay home that they were making for MONTHS. Now they SHOULD be forced to pay for people to stay home while Omicron threatens the general population.
    But masks of ANY kind will help somewhat. Try telling the American male that they will have to shave their beards in order for the N95 mask to work as designed. Try telling older Americans NOT to lift the mask off their face to talk to the store clerk. Try telling that little old lady that the disposable mask she's wearing shouldn't be worn UNTIL the straps break - it needs to be changed out regularly. ("Oh, but it seems like such a waste")
    Indoors air quality as currently operating was for efficiency - ENERGY efficiency. Which is exactly the OPPOSITE of what you need for virus protection. They re-circulate heated or cooled air to reduce energy consumption. It's not the fault of the industry - they are suffering just as badly as we are. We cannot change DECADES of energy efficiency in heating and cooling systems on a dime.
    Wear your mask, the better the mask the better the protection. Get your shot get your boosters. Avoid crowds. Don't travel unless required for business.

  12. Vog46

    BTW Japan is working on a vaccine called the dream vaccine. Supposedly a lifetime of immune protection
    Walter Reed doctors doing pretty much the same thing.
    If successful both these vaccines should be available within 2 years.

    If successful it would be a stunning achievement

  13. Vog46

    One thing people get wrong about filtration is this
    We can certainly use HEPA filters on cruise and airline air handlers
    The problem is NOT with the filters. ITs how the are circulates as it travels to those filters and how often that happens. I stand 6'4" tall and I have to walk stopped over a bit when I get on an airplane. That means that I am walking through the entire air system so to speak.
    There are no safe zones on a plane. Wherever you sit the air is moving TO THE RETURN vents and in most cases it causing contaminated air to go right through YOUR breathing zone. They cannot prevent this from happening unfortunately.
    Cruise ships have the opposite problem, in a sense. They are enormous caverns where they don't more the air ENOUGH to make a huge difference. Same goes for large interior spaces within buildings. They were designed for COMFORT not air purity (which was/is a consideration but secondary to energy efficiency).

    The travel industry is in BIG trouble and they KNOW IT. They are praying that an effective vaccine will be here soon to allow them to go back to their ENERGY efficient ways because energy efficiency INCREASES their bottom line.

    Unless I'm traveling by car with people I know I am NOT going anywhere. If I have to go to a store its very early in the morning to avoid crowds and I am ALWAYS masked

    Schools are going to be making some hard choices soon as COVID hospitalizations among children are rising way too fast, and they are the largest group on unvaccinated Americans.

    With WHO sounding the alarm on future variants because of vaccine "inaccessibility" in many countries we can see the problem. We may be able to survive the Omicron wave but whats next? With OTHER countries having problems getting and distributing the shots we are at the mercy of others to get control over COVID.

    1. painedumonde

      All your comments I agree with: the pandemic is not over and people are prolonging it with inattentive behaviors. Also with the expense and complexity of the engineering controls you mentioned, I began to reflect on why this is. Of course it's money but that's just at first blush. IMO, it's deeper than that, deeper than even economic systems or governing systems.

      I think it's fundamentally human. Look at the haphazard way climate change is being handled even with year after year of predictions fulfilled and data sets added to, all pointing towards an existential crisis for the status quo. Yet we have whistling into the dark, propaganda commercials, space dildos, pipeline construction alongside straw restrictions, financial carbon offsets, and mass demonstrations.

      Anyway, I just wanted to complement your comments.

      1. Spadesofgrey

        The pandemic is essentially over. The fact the omicron strain cannibalize itself to such a degree. As hospitalization collapse this spring to sub pandemic levels, most attempts at following it should be over.

        Trying to compare a long winded "event" like climate change" with a viral outbreak is embarrassing. Your a disgrace to anybody trying to fight against the "Invisible" enemy aka agw.

  14. Citizen99

    From the study Kevin referenced: "More clinical data is required to conclude the efficiency of cloth masks; in the short term, users should not use cloth face masks in the outbreak hot spots and places where social distancing is impossible."
    This is not the same as saying that cloth masks are "lousy." Note the "more clinical data is required" part of this statement.
    My concern is that readers inclined to dislike masks of any kind will conclude that cloth masks are no better than no mask at all. There have been numerous studies showing that this is utterly false. As for the question of aerosolized virus versus droplets, it's simply wrong to conclude that aerosols go right through a mask as if it weren't there. Even cloth masks create a barrier and a tortuous path for aerosolized particles to pass through, and also interrupts the fluid flow that propels the aerosolized particles from the wearer to the outside air. In the reverse direction (inhalation), the fibers are surely going to trap some fraction of aerosolized particles. Advising people to "not use cloth face masks in the outbreak hot spots" is clearly meant to urge the use of more effective masks in such locations, NOT to imply (although the wording unfortunately does) that cloth masks are useless under those circumstances.

    1. KenSchulz

      The only statement anyone should be making about ‘cloth masks’ is, “it depends.” ‘Cloth’ describes a vast range of plant, animal and man-made fibers that can be spun into thread and woven into cloth, or pressed into nonwoven sheet materials (felts, etc.). The characteristics of these materials vary enormously, even within a single fiber type, depending on the production processes. Add to that, that different materials can be combined in a multilayer mask synergistically, so that the mask has properties that the individual components do not*. The parameter space is vast and highly multidimensional and only an infinitesimal fraction has been researched. Many of the relevant properties have no standardized classification or measurement system**. I have read research reports showing certain ‘cloth masks’ being quite effective, others being much less so. No surprise, but little help as researchers can’t specify the materials used sufficiently to be reproduced.
      *My latest cloth masks use polyester between cotton. As the mask flexes, frictional forces generate static-electric charges which attract and hold particles - theory says.
      **Woven fabrics can be characterized by thread count, but at nanoscale the surface properties of the thread are more significant: smooth or ‘shaggy’? The many microfibers on the latter can trap small particles much better.

    1. Vog46

      As it should. Omicron has many more mutations than Delta

      The next variant might evade even the protections provided by Omicron infection.

      We are trying to defeat a living thing that is evolving.

      1. cld

        As distinct from Delta as Omicron is, as we have been hearing, I was surprised that the immune system reaction to it would so fully cover Delta.

        1. Vog46

          The problem with our immune system is that it's reacting slowly to Omicron. By the time it responds Omicron in ****some*** folks has already spread to other organs.
          Omicron is a bronchial infection whereas Delta was fairly deep int he lungs.
          But the different mutations of Omicron is what is causing the immune system response. This is why WHO is worried. COVID has plenty of victims both with expired vaccine protection or who are still NAIVE (NEVER having been infected or vaccinated) outside the EU and US. THIS is where the next variant WILL come from. DELTA developed 50 different strains of itself each differing slightly from the original.
          Omicron came from South Africa.
          The next mutation may have even MORE es-capability from protection than Omicron did and may pose a more severe viral LOAD like Delta did. If this happens 3 months downs the road (like it did between Beta and Delta) immunity protections may have worn off by then
          Remember our vaccines are STILL designed to fight Beta - NOT Delta or Omicron. MOST had efficacy of 90+ against Beta but that dropped to 75 against Delta and to 35 against Omicron. PI immunity was worse !
          There is NO reason NOT to expect more variants. The Spanish flu killed more people in round 4 than the previous 3 rounds
          But we have to get through Omicron first. I would suspect that we may have to shutter schools for a month. Then take away Easter week vacation and extend the school year by 2 additional weeks to make the time up.
          Some communities are already considering this. They admittedly relaxed precautions too soon. And with kids being the largest group of unvaccinated folks? Pediatric hospitals are filling up fast.
          I just hope these miracle vaccines work because once we have them I would feel a whole lot better about the future. Right now I have serious doubts about the spring and summer months. Just like I did during the Beta wave.

          1. Vog46

            That is correct Special
            But everyone ASSUMES that this virus will not continue to evolve, it will stay more like Alpha, Beta Delta and Omicron.
            They are totally discounting that this could get stronger, could get even more evasive and have even more mutations than Omicron has
            And timing is another factor. In previous waves we have had time between waves in some areas. Omicron started in South Africa but spread so quickly due to its evasiveness that we have both Omicron and Delta at the same time.
            We were fully anticipating a surge when schools re-opened and questioned, even back then just how many people COULD get re-infected by an immunity evading variant.

            Immuno compromised people COULD have fostered this mutation OR as pointed out in previous articles, it COULD have been passed to animals and back which is a very bad scenario to be in because PI Immunity declines and our current vaccine immunity also declines with time. Each person reacts differently to the virus as well.
            This is where PI immunity, coupled with not wanting to do testing early plays into the hands of the anti vax people. They just don't know how many NAIVE victims we have left.
            But other countries have a MUCH clearer picture than we do. Their stats are more comprehensive and accurate. They are not tainted by politics or a leaders personal pride.
            So when the S Africans, the Germans The Israelis and the folks in the UK say vaccines fail against Omicron, and PI immunity is even worse they are speaking from a much better knowledge base than we have.
            When you see a country like Israel prepping their folks for Round 4 and we can't even get people to get boosted? This is why I follow their disease parameters MORE SO than ours. Our response was pathetic. Trump did one good thing and that was operation warp speed. But when he lost the election he turned that into a disaster by disparaging the results saying it cost him the election.
            Now that he got COMPLIMENTED by Joe Biden Trump is all "I did that - I created the Trump virus. You should take it."
            And his followers are now aghast at this turn around.
            Watch what happens over seas. Their data is much more complete than ours.
            The israelis fear another round. WHO is saying the same thing. Considering how poorly we gather information in this country? And how we politicize it?
            Yeah, I am concerned. NOT for Omicron, but for whats next

  15. skeptonomist

    Several East Asian countries, for example Japan, have had basically universal masking and have generally had low incidence of covid. However, there are other possible reasons for the difference. Like everything connected with differences between countries, it's too early to sort things out, but maybe there will be better knowledge for the next pandemic.

    1. KenSchulz

      Among the ‘other possible reasons’ are the actions taken by many East and Southeast Asian countries in response to their experiences with SARS-Covid-1 in the early 2000s. Taiwan had a playbook of some 60 action items, and stood up the infrastructure to be ready to implement them. I hope we learn and apply lessons from the current pandemic.

      1. Vog46

        Ken
        Totally agree. WE need to begin to stockpile the most efficient masks we can get our hands on. The problem is we still NEED THEM NOW. There is no next time in that regard.
        But this smacks up against our JIT business model. Storage is a no-no. Over supply is not good, yadda yadda yadda
        I have not been able to find N, or KN 95s here in town since the pandemic started. So be it.
        To me, it makes no difference. If you are wearing a N95 wrong its a waste and I've seen so much of it around here it's pathetic
        But because of this, and the fact that I do care about others. I wear whatever I can get my hands on. Doubled up if necessary between surgical and cloth. I will gladly lend my expertise to anyone who asks for it or just wants to know as I am familiar with respiratory protection. I tell folks I have COPD but can still wear a doubled up mask, and so can they if they have to due to the inability to get N95s.
        Vaccines are the best protection for yourselves. Masks are the best protections for those around YOU. Masks and vaccines are better for everyone and we should be doing both.But no matter what, those with comorbidities are at risk and we have far too many of those people here in the United States.
        And we are so damned proud of ourselves for being "Murican" that we feel like we earned the right to eat ourselves into diabetes, IBS, and a host of other immuno-compromising diseases. And we damned sure don't need to care about that person next to us - we're Americans. We can do what we want, when we want without a care in the world.
        Our vaunted free enterprise, for profit healthcare system is a failure and there's no amount of changing the parameters of reports of death and illnesses that will change that. There's no amount of alternative treatments that will make this better.
        We NEED to do better next time, but we won't

    1. rational thought

      Anyone else wearing the kn94 masks which are the Korean version of n95?

      I think they are possibly just a touch less effective ( i.e. 94 vs 95) but I find them much more comfortable to wear and also to fit to your face ( which might mean they are in practice more effective than n95). In fact, I find them more comfortable than cloth masks.

      If I had to wear a mask all day working like some, no way could I wear n95 masks , so I could see some just going with cloth. But kn94 is more tolerable to me which makes them as a choice instead of cloth more workable for many, if they have the same experience.

      Just wonder if others think the same and if trying them might be a good option .

      1. D_Ohrk_E1

        KF94. Yeah, I prefer the KF94 type masks. Much more breathable.

        The distinction between N95/KN95/KF94 is moot -- they're minimum filtration ratings under different standards bodies.

        In most cases, they're all at or around 99% average filtration rate. Here's one KF94 -- https://is.gd/Uv7Fgi and one N95 -- https://is.gd/AH4ceq

        The problem, of course, with Chinese-sourced KN95 masks, is that not all perform as advertised.

  16. rational thought

    This is what I have been talking about re original antigenic sin which is an important concept not discussed enough.

    What it means is that your immune system will tend to stay more focused on the FIRST infection you had and not fully adjust for a new variant after being infected with that .

    As the vaccine is based on original , anyone vaccinated before infection, or who first got infected with original, should have future immunity stay somewhat focused on original, no matter what variant they are later infected with. And same for delta first infections.

    As there likely will be almost nobody first infected with omicron , and we cannot distinguish them as so many asymptomatic cases, we likely will never really know what sort of omicron immunity would result from a first omicron infection. But any omicron immunity from an omicron infection first should be better than what we will get from secondary omicron infection.

    There is a tradeoff. Strong original antigenic sin would produce great immunity for prior variants ( driving them extinct ) but with weak immunity for the new dominant omicron , making it a worse endemic virus. But real weak or nonexistent original antigenic sin would mean your immune system gets reset to omicron giving delta a chance to come back and you can end up with alternating waves.

    Overall, given that omicron is less virulent, something in between is the sweet spot. Giving a delta immunity boost enough to drive it to extinction with weaker but still good enough omicron immunity.

    This preliminary result looks just about ideal.

    1. Jimm

      You're overthinking all of this again, at the expense of the actual available evidence, and there's no such thing as a "delta immunity boost".

  17. Vog46

    This didn't take long.
    Yesterday Mexico decided to ALLOW cruise ships back in.
    Today we have this:
    https://www.dailymail.co.uk/news/article-10353459/Carnival-cruise-ship-docked-Mexico-69-positive-COVID-cases-wont-allow-exit.html
    {snip}
    More than 3,000 passengers aboard a cruise ship carrying 69 people infected with COVID were reportedly blocked for disembarking by Carnival Cruise Line after health officials in the western Mexico state of Jalisco requested negative tests for all traveler who sought to leave the liner.

    Mexico news outlet Milenio reported on Tuesday that the Jalisco state health department made the request after the Carnival Panorama docked in the Pacific resort city of Puerto Vallarta on Monday around 9:00 a.m local time.

    The health department decision to allow the non-infected passengers to disembark only came after the Mexican government’s Health and Tourism ministries agreed earlier this week to allow vacationers off the ship in accordance with the World Health Organization’s (WHO) International Health Regulations.
    {snip}

    So they said yes but then said ONLY if you have negatives test results from the people disembarking and now Carnival is saying no?

    This is just another example of the sheer stupidity of allowing cruising to start back up.
    What's next?
    I think that we will soon be looking at temporary school closings - already started with several universities resorting to online for the start of spring semester.
    If this happens how long will it be before the DEMs and republicans do battle about another handout to businesses and individuals?

  18. D_Ohrk_E1

    Masks reduce viral load, which is critical with Omicron and its significantly higher viral load in the upper respiratory tract. You can get exposed to viruses at a lower viral load and not get "infected". Higher initial viral loads at exposure tend to have worse outcomes, too.

    If this weren't true, there'd be no point to ever wearing a respirator/mask in hospitals.

    Are vaccines better than masks? This is a false choice. They supplement each other to reduce your total risk. You could go w/o vaccines or a mask for a very long time without getting infected and conclude that neither was critical, but that involves a couple of cognitive biases.

Comments are closed.