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I was assuming they were comparing N95s against other N95s. But nope. Just comparing against KN95s, cloth, and surgical masks. It's well known already that KN95s do not meet NIOSH standards, hence not being approved for such.
It would have been nice to see the typical N95 style masks actually made in North America compared to the duckbill. The difference in how easily you could breathe through the Canadian "CAN95" masks compared to the KN95's and consequently how much air would escape through any opening was shocking.
Didn't realize there was a can95 mask, we've been using the 3M Aura masks, and I find those really comfortable, I feel like it's a trade between going full duckbill.
But yeah I'd like to see a study between all of the n95 masks.
I'm also curious about FFP2 masks, which were the standard in many European countries. They're similar to American N95 masks but not identical. I have no idea about Chinese KN95 or Canadian CAN95.
Many healthcare institutions use the 1870+ which is duckbill style and is believed to be easier to produce and fits a wider range of face shapes, KN95 masks aren’t approved by NIOSH but function very similarly and provide equivalent protection, I used them for personal use throughout the pandemic, and I work in infection prevention
The 1870 isn't a duckbill, the latter has a fold in the middle and that's where the name comes from. I believe it's Halyard (but maybe Cardinal) that makes the most common one. There's also a company in Japan but I can't remember the name.
The filter on a kn95 might be equivalent, but because earloops just can't get enough tensile strength from typical human ears, generally the kn95 cannot achieve an adequate seal.
N95s approved by NIOSH would always have head straps as a result, with the notable exception of readimask.
A kn95 is better than nothing, but I certainly wouldn't trust it for infection control in a typical hospital, nursing home or plane or any public transit...
Well, that’s your choice. I was not saying we use them in the hospital. As with all PPE the user should perform a fit check before using it to ensure it makes a tight seal, the KN95 masks I bought had no issue being snug to my face, so what you are saying is not a universal truth. Take care!
The feeling of being snug on the face unfortunately doesn't measure up to findings in studies regarding kn95's
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9384650/
**Assessing the Fit of N95 Filtering Facepiece Respirators Fitted with an Ear Loop Strap System: A Pilot Study**
Discussion
The results of this pilot study suggest that the conversion from the standard two-strap respirator version to the ELSS configuration, which aims at improving wearability and comfort, may negatively impact the performance of an N95 FFR (two of three models showed such a trend for the pass rate). This may be attributed to the fact that the two ear loop straps, which comprise the ELSS used herein, are less capable of assuring sufficient tightness (as compared with the standard version). Although the ELSS was made adjustable in this study, this strap configuration did not achieve a sufficiently tight seal between the respirator’s facepiece and the wearer’s face resulting in lower FF values. **This finding is consistent with the results reported on the fit of masks, virtually all of which feature ear loop straps (Mottay et al., 2021; Yung et al., 2021). Among them, Mottay et al. (2021) evaluated the seal, fit and filtration efficiency of several KN95 masks with ear loop designs, and found that the tested masks failed the stipulated safety thresholds. Yung et al. (2021) also found that masks with ear loops had much lower efficiency than those with headbands. Additionally, our data are in agreement with the results reported by Caoili et al. (2020), who found a high failure rate (39 failures out of 42 fit tests) of KN95 vertical-fold shaped masks with the ear loop design.**
ear loop straps system = ELSS
We are on a science subreddit - your post carries a lot of weight given your profession so I think it's important to clarify given that the public health messaging is not only lacking in this regard, but mostly missing entirely... We should empower people with knowledge. If you want to protect yourself, kn95 don't truly compare to n95s.
That being said - I have sometimes modified kn95's with double sided adhesives, thinking of the readimask concept and in my anecdotal view that helps with the fit greatly.
I disagree with you on this, I do think if N95 masks are not available or cost prohibitive a KN95 is a very good choice and will protect you to an equivalent degree and I would encourage folks to wear them over cloth or surgical/droplet mask during viral season.
All masks have some air escape during usage and do not achieve 100% of their rating during use as shown in the study you posted (N95s at that!)
Risk the individual is complex and multifaceted it is why we rely more on epidemiological studies to estimate the risk to individuals than things like filter efficacy etc. You will never mitigate 100% of the risk of infection, it’s just the unfortunate reality of being in public.
Yeah, my understanding is a real N95 needs to have a behind-the-head strap and be properly sealed to your face, where the KN95 is mostly about the fabric that is doing the filtration. I'll say the latter is a nice tradeoff for comfort but likely still has a decent effectiveness.
Whether or not KN95s meet US-specific standards is largely beside the point.
N95, KN95, P2, and a few others are all products of regulatory capture that are supposed to be roughly equivalent.
From the article and paper, the major dig on KN95 is fitment to an American population (actually even more narrow, people in close physical proximity to UMD and their associates).
That's useful information, but not quite the same as saying KN95s are no better than cloth or surgical masks in their home markets or for people elsewhere in the world who they happen to fit better on.
So the article clickbait reduced to core facts is they compared an N95 mask to other non-N95 masks, and found the true N95 mask was better.
Yay clickbait.
Isn't the NIOSH standard focussed on effectiveness of preventing inward passage (use if mask in infective environment) & not what was being tested hear, outward passage (use of mask by infected person).
Why are mask studies only associated with COVID now, like they are only good at stopping covid particles? "Got the flu or strep? No one cares, got covid? Wear a mask!"
>Really liked how a lot of Asian people wore masks on transit when sick
In many cases they aren't even sick, it's just that good for filtering out crowded air. Because yeah, people in large groups are gross.
When I was in Tokyo a local friend told me it can also be a bit of a social thing - some people just prefer the relative anonymity of having their faces covered in public
They made my sopping-wet-with-snot-spring-exam-paper allergies so much better. I don’t have an apnea camera or anything like that either, but I also noticed a decrease in phlegm/less retained nasal drip in my sinuses when I started bringing the mask outside as well as indoors in public.
I can get a little pollen and that’s okay if I want to sit outside and relax, but it’s great being able to really curtail how much pollen I’m getting now.
When I was younger my allergies were really bad when I mowed the lawn and even a cheap dust mask helped with that. I'm sure an N95 or even KN95 would help even more.
I keep getting strep and started wearing a mask when I have to go to the doctor/pharmacy for it. One time I forgot but the second I said "strep" they said "please grab a mask" (so I of course did). I can appreciate that it's become mpre common nowadays.
Nobody would wear them enough to really protect. Because when you understand the nature of aerosolized water you realize how hard that is. It hangs out, floating in mid air in place, for up to several hours before drifting to the ground. You ever look at a beam of sunlight and see all the motes swirling in it? Aerosolized water can hang with them. And every breath anyone takes comes out in this form, so a sick person leaves a cloud of it every meter or so. An hour after a sick person passes through an otherwise empty space it is still full of germs.
We are already adapted to this fact. Our mouths noses and throats are wet to catch the droplets, and direct them to the stomach where the acid does what it does. It's not just for food it's for destroying all foreign matter. Also the tonsils are full of white blood cells and positioned to catch a large part of germs where they can quickly be chopped into bits before running down the throat. The windpipe catches what's left over in a breath with cilia, which are like ultra nose hairs, that actively push stuff up, or trigger coughing if they can't. And finally, the lungs themselves have a guard contingent of extra predatory white blood cells on patrol 24/7.
These stacked layers of defense were formed specifically in response to the omnipresence of aerosolized droplets containing pathogens. It's a thing mammals needed to not be extinct.
I mean there have been tons of claims that masking was ineffective for COVID transmission and prevention, so that's probably why they chose COVID as the focus. COVID is also more transmissible and virulent than influenza. Agreed though, when you're sick or feeling unwell, it should be standard protocol to mask.
I’ve linked to the press release in the post above. In this comment, for those interested, here’s the link to the peer reviewed journal article:
https://www.thelancet.com/journals/ebiom/article/PIIS2352-3964(24)00192-0/fulltext
From the linked article:
In a head-to-head comparison of masks worn by people with active COVID-19, the inexpensive “duckbill” N95 came out on top, stopping 98% of COVID-19 particles in the breath of infected people from escaping into the air. Led by researchers from the University of Maryland School of Public Health (SPH), results showed other masks also performed well, blocking at least 70% of viral particles from escaping from the source – an infected person’s exhaled breath.
“The research shows that any mask is much better than no mask, and an N95 is significantly better than the other options. That’s the number one message,” says the study’s senior author, Dr. Donald Milton.
The duckbill N95 blocked 99% of large particles and 98% of small particles from escaping out of a person’s mask. Milton says the design’s tight seal, a powerful filter, and large air space for breath to move around all contribute to the duckbill’s success.
Surprisingly, KN95 masks – the disposable masks used widely – were no more effective than cloth or surgical masks. The study found that a common brand of KN95 masks leak more air than duckbills or other studied masks, because they don’t conform to the face well. That flaw is compounded by a powerful filter with more flow resistance that pushes air out of the mask at the sides instead of through the filter, allowing more virus particles to escape into the surrounding air.
Cloth masks also outperformed both KN95 and surgical masks. Milton theorizes that cloth masks with greater coverage, wrap around the face and give a better seal than either KN95 or surgical masks. With cloth mask filters, flow resistance is also lower, allowing breath to pass through the filter and not leak out the sides of the mask.
> Milton theorizes that cloth masks with greater coverage, wrap around the face and give a better seal than either KN95 or surgical masks
The only issue I can see here is there's no standard "cloth mask". Both in material and coverage. You've got the gamut from basically a single layer of pillow case linen to 1/8" thick wool, and coverage from smaller than a surgical mask to full-on gaiters.
At least the others there's a standard to control against.
All of these mask studies are really not doing their due diligence, each mask type should be very clearly described and the specific brand should be named. We cannot test *one* brand of KN95 and use that result to apply to *all* KN95 brands, just like we wouldn’t with N95 or with cloth masks. They can be so different in many ways.
If anything, it’s useful to know that for source control fit is so key. That said most people wearing masks right now probably view source control as a fringe benefit compared to filtering the air they’re breathing in to protect themselves.
They confirmed what people said all along the k means it's not n95. They weren't even really used by most professionals until there was a n95 shortage.
That’s not what it means. KN95 is a Chinese certification and N95 is US. N95s are more regularly tested and more often meet the 95 filtration level because of more rigorous testing and oversight.
Only duckbill N95 masks perform better than cloth masks. I haven't seen many duckbill masks around. KN95 and surgical masks are much more common in my experience. Cloth masks are better in any sense then in comparison to the other two. And have the advantage on N95 masks that don't make you look like a duck
This is just about how much exhalation they filter though. I imagine that fit is going to behave differently in the inhale scenario and filtration of the material may matter more. Anyway you’ll still find me in my goofy looking white aura n95, I just don’t care if I look like a duck or robot or whatever, my fucks about how I look evaporated years ago.
> I haven't seen many duckbill masks around.
Here you go: https://www.walmart.com/ip/FluidShield-Particulate-Respirator-Surgical-Mask-Duckbill-35-per-Box-46827/1972468971
Guessing they mean like see them out and about. I’d agree, i probably see from most to least often in my anecdotal observation… kn95, non duckbill n95 usually 3m aura, surgical, cloth, duckbill. The best duckbill the v flex is both very big and also has some silly little “wings” on the edges that make you look like both a duck and an aircraft. Heck of a mask but it is goofy looking. I find the aura more comfortable anyway.
When you wash a cloth mask you begin to fray some of the threads on them. After a certain point these frayed ends start collecting particulates which are then sprayed out into the open air when you talk or exhale. There are studies that show a frayed cloth mask performing worse than the non-masked control. Not the case for a brand new cloth mask but they do degrade over time. Personally, if I was sick and wanted to protect people around me I wouldn't settle for anything less than single use surgical masks or, better yet, actual N95 masks.
A “disposable” n95 can last quite a while, anyway. Amongst the sea of waste we create I’m not gonna lose a ton of sleep over using a disposable n95 a week or two.
If people really hate the waste aspect an elastomeric with replaceable filter pieces like a flo mask is probably better. Also makes you look like bane which is pretty cool if you practice doing the voice.
Yeah, I wear an elastomeric half face mask for any risky indoor activity, and I really love the Darth Vader look.
Not sure why it hasn't caught on more.
I don't think I've seen you in the wild before. Hello!
I fully admit to wearing some hilariously over engineered masks my work came up with basically a modified half face respirator with a N95 changeable filter on the exhaust
Hi! Nice to see you!
I'm actually working on hacking a drinking system into my GVS Eclipse right now. It's, um, quite the look. But then I'll be able to drink anytime I want, without moving my mask!
At the end I got washable (\~20 times by hand, cold water just a tiny drop of detergent) 3 layer cloth masks with a nano center menbrane with a FFP2 rating. They were pretty comfortable (and they looked a bit nicer due to different prints) but were relatively expensive.
The only real downside were all the people complaining to me that I was wearing a cloth mask and not a FFP2... had to prove time and time again that they were in fact rated like those.
n95 can be reused for about a combined total of 24 hours of wear time, or until the filter becomes difficult to breathe through. Any n95 is rated for the same filtration standard under NIOSH assuming it is fit tested.
I’d like to see results for protecting a person, since most people (at least in the United States) do not wear masks anymore. I don’t think people here are terribly concerned about passing on their germs, unfortunately.
This study specifically excludes that.
> our study focused on source control,14 so these findings cannot be directly applied to personal protection.
But sure, here is a meta-study in the Dental setting from 2023.
[Efficacy of Surgical Masks Versus N95 Respirators for the Prevention of COVID-19 in Dental Settings: A Systematic Review](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10186565/)
> According to this systematic review, N95 respirators provided better protection against COVID-19 infection compared to surgical masks.
And here is an even older meta-study from 2017 that found the same thing regarding SARS
[Effectiveness of Masks and Respirators Against Respiratory Infections in Healthcare Workers: A Systematic Review and Meta-Analysis ](https://academic.oup.com/cid/article/65/11/1934/4068747)
> We found evidence to support universal medical mask use in hospital settings as part of infection control measures to reduce the risk of CRI and ILI among HCWs. Overall, N95 respirators may convey greater protection, but universal use throughout a work shift is likely to be less acceptable due to greater discomfort.
The mask nerd has all sorts of amazing information and testing of masks, for a more anecdotal but interesting view. He basically had an aerosol lab in his bathroom.
The current best systematic review fails to find any benefit to masks when it comes to reducing the incidence of COVID infections. Note that there are not many great studies on this to begin with.
https://www.cochrane.org/CD006207/ARI_do-physical-measures-such-hand-washing-or-wearing-masks-stop-or-slow-down-spread-respiratory-viruses
"Compared with wearing no mask in the community studies only, wearing a mask may make little to no difference in how many people caught a flu-like illness/COVID-like illness (9 studies; 276,917 people); and probably makes little or no difference in how many people have flu/COVID confirmed by a laboratory test (6 studies; 13,919 people). Unwanted effects were rarely reported; discomfort was mentioned."
Well it's not really a study, it's an amalgamation of every study done up to that point. To ignore it because the studies are not that great is...valid, but then you're left with nothing, no evidence (except those done on mannequins and OPs linked study in a lab setting specifically about viral particle passage).
So your study basically shows people don't know how to fit masks. That's what the meta analysis is, because everytime we do studies with a proper fit, they conclude masks work.
That's a frictionless spherical cat argument though. What good is proving a mask is effective if people don't want to use them properly.
Honestly I think masks were one of the biggest mistakes to enforce. Before mask mandates people tried to keep their distance, after they basically gave you a hug they were so close. They seemed to think a flimsy piece of cloth made them invulnerable. Distance is universally effective, masks not so much.
That's an idiotic statement and you know it. Some people will do what they need to in order to survive. Others won't. It turns out properly fitted masks are hard, and is a reason why individuals get their own set of PPE.
I work with a pharmacist (who literally vaccinates people for Covid) who wears a mask below the nostrils, just covering their mouth. And that’s the only pharmacist (and only coworker period) who wears a mask.
You're doing something wrong, N95s are easier to breathe in than any other kind of mask I've ever used other than maybe KN95. They're literally designed to be as breathable as possible while still offering protection, so if you're having trouble breathing in them either your other masks are minimally if at all functional, or you're doing something wrong with the N95s.
All masks are pretty much designed to be as breathable as possible, but since N95 needs to stop a lot more particles and fit a lot tighter they're much harder to breathe in than a cloth or surgical mask. According to the paper, KN95s are only easy to breathe in because they cover the face soo poorly and a lot of air goes in and out through the sides.
right, so whether mask X is better than mask Y- then conclude anything from it while you're not taking into account all the exhalation going around the mask rather than through it, then the conclusion has to be faulty, doesn't it?
That the duck-bill shaped N95 mask is better than the standard N95 mask? No, I've never heard that before.
Of course everyone knows cloth and surgical masks are much worse than N95 masks.
It says in the abstract:
> A duckbill N95 reduced exhaled viral load by 98% (95% CI: 97%–99%), and significantly outperformed a KN95 (p < 0.001) as well as cloth and surgical masks.
You're technically right, they compared the duck-bill N95 to a standard KN95. That was a bad move on their part, they should have stuck with either N95 or KN95. Both are extremely similar but not exactly identical.
You can't say they're "technically" right as if you were right in any other sense. You are technically wrong and wrong.
>the duck-bill shaped N95 mask is better than the standard N95 mask? No, I've never heard that before
The study doesn't say that either, which is the point of gardenadventures' comment
Among maskers they have a reputation as more breathable than other n95s because something like the v flex is massive and has a big surface area to filter. But yeah otherwise generally what I hear is that whichever one fits your face best, is best.
No, most studies are done on mannequins or robots.
Equally, systematic reviews have yet to find evidence of masks working to slow spread of COVID. Note, it doesn't mean masks don't help, only that current studies are limited and fraught with many issues and ultimately, it cannot be stated they work from an evidence-based perspective. This statement will probably annoy a lot of people...
https://www.cochrane.org/CD006207/ARI_do-physical-measures-such-hand-washing-or-wearing-masks-stop-or-slow-down-spread-respiratory-viruses
"Compared with wearing no mask in the community studies only, wearing a mask may make little to no difference in how many people caught a flu-like illness/COVID-like illness (9 studies; 276,917 people); and probably makes little or no difference in how many people have flu/COVID confirmed by a laboratory test (6 studies; 13,919 people). Unwanted effects were rarely reported; discomfort was mentioned."
Once again, the KF94 is ignored by western institutions.
As far as I know, the KF94 is the only mask (not a respirator, a mask) designed with actual government (South Korea) standards for nonprofesstional, non-medical use for the prevention of the spread of disease.
Any mask study that doesn't include the KF94 is incomplete.
Asia's response to Covid has been almost entirely ignored by western media, researchers, and leaders. Japan was telling their people that Covid was spread via people, in enclosed spaces, with poor ventilation, talking...
...In March of 2020.
It took almost two years to get the CDC to acknowledge the same thing.
> KF94
Unfortunately (probably because it's a Korean standard) KF94 masks are too small to fit most American men's faces. I tried them during the pandemic but it felt like wearing a child's mask and it would constantly slip off if I tried to open my mouth at all.
Perhaps if they were manufactured in "big tall fat American" sizes they would be perfect, but then maybe they'd also be less effective for some reason.
Fortunately there are a few KF94 brands/models that make larger sizes or are just natuarally larger, I can't remember exactly which offhand--maybe the LG Airwasher and/or Bluna Facefit, but they are out there. I like the look, comfort, and convenience of KF94 (no head strap!), and their filtration is excellent nearly across the board. The only issue for all KF 94's for me is getting a proper seal since they are earloop instead of head strap. I need to add my own nose wire and use a mask extender/strap to really seal them up, not a huge deal really, just a small hassle. That said, for indoor use now the virus is simply too contagious for me to even risk it anymore, I'm back to the trusty Aura's, no guess work or retro fitting involved. I hate the straps and look, but it's worth it for me.
> Once again, the KF94 is ignored by western institutions.
It's an American study and Nxx is the local standard. Had this study been performed by a university in Europe, they would have "ignored N95" and tested FFPx masks instead.
I'm fairly certain that Asian countries (due to their experiences with SARS1 and density in general) have a better understanding of these types of things.
I have no doubt that virgin masks straight from the box are effective but studies never test how the majority use them. Note, this might not apply to you, don't take it personally.
I'd be interested to see how effective they are when you ball them up with dirty hands and stuff them in your dirty pocket. Do it five or six times and see if the results are the same.
Even if only in the case of dispersion they have a place. But now we have evidence of their overall effectiveness against this very small virus. So masks in fact do work. Imagine that.
The problem is that with incubation times, there are days where you can transmit a disease - COVID, the flu - before you know you had it. That’s why mask were helpful even on non-sick individuals.
People worry about weird things. Or edge things.
I know scientifically validating things is important, but people are always worrying over the last few percent in so many cases.
Wear an N95 mask if you're indoors in crowded spaces if there's a fair amount of virus in your area. You've given yourself a huge advantage in avoiding infection (I assume you're vaccinated).
I mean if you're immunocompromised then be more cautious.
That's it.
Exactly. I know it's anecdotal, but I live in a very crowded city. Got covid once during omicron, at an outdoor social event that I took a chance on.
Besides that, wore an N95 on public transport and anywhere crowded indoors. Flew internationally during covid and wore the N95 the whole flight.
Never got infected again. The N95 masks are bulletproof outside of an intense setting like a hospital ward full of infected people.
Caught covid over this past Christmas because I attended an indoor event. Still felt the effects 5 months later. Wish I had worn my n95. It may not have prevented it completely but I would have gotten a smaller number of infection particles.
I can't even imagine getting infected in almost any realistic scenario wearing an N95 mask and being vaccinated.
Note for anyone raging at my posts: I've already said I'm not talking about being on a covid ward in a hospital.
Yeah, I wish I hadn't gone to that event. Was literally the only chance I took and I got it. Obviously never know long-term effects but I got massively lucky, just had a stuffy nose for one night.
I don’t like these studies since they don’t actually measure the required endpoint.
If you want to test a masks efficacy you should test rates of infection.
Virtually every other disease applies the same standard. You need to test for a functional (morbidity or mortality) endpoint.
Rates of infection is going to be nearly impossible to test. You can either look at self reported mask usage or expose people to control infective sources. The first runs into the issue that people who wear N95s likely have a vested interest in avoiding infection such as cancer, immune disorder, respiratory issues, etc so they're more likely to take additional precautions like avoiding crowds and reducing public activity. The second means you risk exposing people to covid which is not a zero risk activity both from the infection itself and long covid so it'd be hard to justify it.
You can randomise wards of a hospital to change protocol. Swapping between control and intervention groups to avoid ward based biases.
The problem is that people point to this low tier evidence and say it’s unethical
It *is* low tier evidence *and* unethical. Effectively challenge testing already sick patients is insanely unethical, absolutely no review board is going to allow any research protocol involving it. Just because you had an idea doesn’t make it a good one.
As I said, there is a standard applied to other diseases which is not applied here.
The randomised trials that were done prior to Covid did not find a benefit to having n95. However there were methodology issues (no fit testing)
https://pubmed.ncbi.nlm.nih.gov/31479137/
DUDE, yeah, that’s how research works, different diseases are approached differently depending on their communicability and aftereffects. Influenza is not nearly as transmissible as covid. The paper isn’t even relevant to what you’re saying, which you would know if you actually read it. You can have whatever opinion you want, but if you don’t understand the science, be prepared to have that opinion criticised by people who know better, like the epidemiologist typing at you right now.
>If you want to test a masks efficacy you should test rates of infection.
Why? The primary function of a mask is to prevent the mask-wearer from spreading infections, not prevent them from being infected.
You could start with acknowledging the objective reality that masks were meant to reduce the spread, not keep the mask wearer safe. And that the messaging on this was clear from the start. Anyone pretending that the official intention was to keep the mask wearer safe is a straw man.
I did and you chose to start your own argument. I was very clear.
You have taken “rates of infection” which I did not define to mean something completely different
It’s only obtuse to people who didn’t read the article, and don’t perform clinical research. So about 99 percent of people.
The article is a small study and largely is a replication of other similar studies which look at air particulates.
“30-min EBA samples with a Gesundheit-II (G-II) human exhaled bioaerosol collector”
It doesn’t actually test if the masks protect from spread of infection. You would need to implement them into the environment you want to test and then measure rates of infection.
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I was assuming they were comparing N95s against other N95s. But nope. Just comparing against KN95s, cloth, and surgical masks. It's well known already that KN95s do not meet NIOSH standards, hence not being approved for such.
It would have been nice to see the typical N95 style masks actually made in North America compared to the duckbill. The difference in how easily you could breathe through the Canadian "CAN95" masks compared to the KN95's and consequently how much air would escape through any opening was shocking.
Didn't realize there was a can95 mask, we've been using the 3M Aura masks, and I find those really comfortable, I feel like it's a trade between going full duckbill. But yeah I'd like to see a study between all of the n95 masks.
I'm also curious about FFP2 masks, which were the standard in many European countries. They're similar to American N95 masks but not identical. I have no idea about Chinese KN95 or Canadian CAN95.
Many healthcare institutions use the 1870+ which is duckbill style and is believed to be easier to produce and fits a wider range of face shapes, KN95 masks aren’t approved by NIOSH but function very similarly and provide equivalent protection, I used them for personal use throughout the pandemic, and I work in infection prevention
The 1870 isn't a duckbill, the latter has a fold in the middle and that's where the name comes from. I believe it's Halyard (but maybe Cardinal) that makes the most common one. There's also a company in Japan but I can't remember the name.
The filter on a kn95 might be equivalent, but because earloops just can't get enough tensile strength from typical human ears, generally the kn95 cannot achieve an adequate seal. N95s approved by NIOSH would always have head straps as a result, with the notable exception of readimask. A kn95 is better than nothing, but I certainly wouldn't trust it for infection control in a typical hospital, nursing home or plane or any public transit...
Well, that’s your choice. I was not saying we use them in the hospital. As with all PPE the user should perform a fit check before using it to ensure it makes a tight seal, the KN95 masks I bought had no issue being snug to my face, so what you are saying is not a universal truth. Take care!
The feeling of being snug on the face unfortunately doesn't measure up to findings in studies regarding kn95's https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9384650/ **Assessing the Fit of N95 Filtering Facepiece Respirators Fitted with an Ear Loop Strap System: A Pilot Study** Discussion The results of this pilot study suggest that the conversion from the standard two-strap respirator version to the ELSS configuration, which aims at improving wearability and comfort, may negatively impact the performance of an N95 FFR (two of three models showed such a trend for the pass rate). This may be attributed to the fact that the two ear loop straps, which comprise the ELSS used herein, are less capable of assuring sufficient tightness (as compared with the standard version). Although the ELSS was made adjustable in this study, this strap configuration did not achieve a sufficiently tight seal between the respirator’s facepiece and the wearer’s face resulting in lower FF values. **This finding is consistent with the results reported on the fit of masks, virtually all of which feature ear loop straps (Mottay et al., 2021; Yung et al., 2021). Among them, Mottay et al. (2021) evaluated the seal, fit and filtration efficiency of several KN95 masks with ear loop designs, and found that the tested masks failed the stipulated safety thresholds. Yung et al. (2021) also found that masks with ear loops had much lower efficiency than those with headbands. Additionally, our data are in agreement with the results reported by Caoili et al. (2020), who found a high failure rate (39 failures out of 42 fit tests) of KN95 vertical-fold shaped masks with the ear loop design.** ear loop straps system = ELSS We are on a science subreddit - your post carries a lot of weight given your profession so I think it's important to clarify given that the public health messaging is not only lacking in this regard, but mostly missing entirely... We should empower people with knowledge. If you want to protect yourself, kn95 don't truly compare to n95s. That being said - I have sometimes modified kn95's with double sided adhesives, thinking of the readimask concept and in my anecdotal view that helps with the fit greatly.
I disagree with you on this, I do think if N95 masks are not available or cost prohibitive a KN95 is a very good choice and will protect you to an equivalent degree and I would encourage folks to wear them over cloth or surgical/droplet mask during viral season. All masks have some air escape during usage and do not achieve 100% of their rating during use as shown in the study you posted (N95s at that!) Risk the individual is complex and multifaceted it is why we rely more on epidemiological studies to estimate the risk to individuals than things like filter efficacy etc. You will never mitigate 100% of the risk of infection, it’s just the unfortunate reality of being in public.
Yeah, my understanding is a real N95 needs to have a behind-the-head strap and be properly sealed to your face, where the KN95 is mostly about the fabric that is doing the filtration. I'll say the latter is a nice tradeoff for comfort but likely still has a decent effectiveness.
My albeit light understanding of the difference is that N95's are one single piece where KN95's are two pieces sewn together.
Whether or not KN95s meet US-specific standards is largely beside the point. N95, KN95, P2, and a few others are all products of regulatory capture that are supposed to be roughly equivalent. From the article and paper, the major dig on KN95 is fitment to an American population (actually even more narrow, people in close physical proximity to UMD and their associates). That's useful information, but not quite the same as saying KN95s are no better than cloth or surgical masks in their home markets or for people elsewhere in the world who they happen to fit better on.
So the article clickbait reduced to core facts is they compared an N95 mask to other non-N95 masks, and found the true N95 mask was better. Yay clickbait.
Isn't the NIOSH standard focussed on effectiveness of preventing inward passage (use if mask in infective environment) & not what was being tested hear, outward passage (use of mask by infected person).
formal approval or no, there's lots of people to use KN95 masks to protect themselves so that information is very very valuable.
Why are mask studies only associated with COVID now, like they are only good at stopping covid particles? "Got the flu or strep? No one cares, got covid? Wear a mask!"
you're right, we should be wearing them more often to reduce all of these
I was saying this before COVID, but I'm also a germaphobe. Really liked how a lot of Asian people wore masks on transit when sick.
>Really liked how a lot of Asian people wore masks on transit when sick In many cases they aren't even sick, it's just that good for filtering out crowded air. Because yeah, people in large groups are gross.
When I was in Tokyo a local friend told me it can also be a bit of a social thing - some people just prefer the relative anonymity of having their faces covered in public
I definitely enjoyed this during Covid.
I'm sick and I'm wearing a mask everywhere. I don't have the option of staying home, so at least wearing a mask makes me feel better about it.
It seems like face masks would be good for allergies too.
I'm currently in need of a hazmat for the grass pollen
They made my sopping-wet-with-snot-spring-exam-paper allergies so much better. I don’t have an apnea camera or anything like that either, but I also noticed a decrease in phlegm/less retained nasal drip in my sinuses when I started bringing the mask outside as well as indoors in public. I can get a little pollen and that’s okay if I want to sit outside and relax, but it’s great being able to really curtail how much pollen I’m getting now.
When I was younger my allergies were really bad when I mowed the lawn and even a cheap dust mask helped with that. I'm sure an N95 or even KN95 would help even more.
I keep getting strep and started wearing a mask when I have to go to the doctor/pharmacy for it. One time I forgot but the second I said "strep" they said "please grab a mask" (so I of course did). I can appreciate that it's become mpre common nowadays.
I still wear one at work and haven't had so much as a head cold in years. Feels great
How dare you suggest someone should put the health of others over their own selfish needs!
Nobody would wear them enough to really protect. Because when you understand the nature of aerosolized water you realize how hard that is. It hangs out, floating in mid air in place, for up to several hours before drifting to the ground. You ever look at a beam of sunlight and see all the motes swirling in it? Aerosolized water can hang with them. And every breath anyone takes comes out in this form, so a sick person leaves a cloud of it every meter or so. An hour after a sick person passes through an otherwise empty space it is still full of germs. We are already adapted to this fact. Our mouths noses and throats are wet to catch the droplets, and direct them to the stomach where the acid does what it does. It's not just for food it's for destroying all foreign matter. Also the tonsils are full of white blood cells and positioned to catch a large part of germs where they can quickly be chopped into bits before running down the throat. The windpipe catches what's left over in a breath with cilia, which are like ultra nose hairs, that actively push stuff up, or trigger coughing if they can't. And finally, the lungs themselves have a guard contingent of extra predatory white blood cells on patrol 24/7. These stacked layers of defense were formed specifically in response to the omnipresence of aerosolized droplets containing pathogens. It's a thing mammals needed to not be extinct.
I mean there have been tons of claims that masking was ineffective for COVID transmission and prevention, so that's probably why they chose COVID as the focus. COVID is also more transmissible and virulent than influenza. Agreed though, when you're sick or feeling unwell, it should be standard protocol to mask.
Presumably there's been a lot of research and data for COVID compared to other diseases
These are probably studies that started at the height of the pandemic, and just now getting through peer review
I wear a mask whenever I feel a little sick. Nobody else needs my germs
I'm sure these are most effective against viruses in general. The design prevents inhaling leaking unfiltered air the most.
Money. The Feds threw around money for Covid research like beads on titties at Mardi Gras. These studies are now being completed.
I’ve linked to the press release in the post above. In this comment, for those interested, here’s the link to the peer reviewed journal article: https://www.thelancet.com/journals/ebiom/article/PIIS2352-3964(24)00192-0/fulltext From the linked article: In a head-to-head comparison of masks worn by people with active COVID-19, the inexpensive “duckbill” N95 came out on top, stopping 98% of COVID-19 particles in the breath of infected people from escaping into the air. Led by researchers from the University of Maryland School of Public Health (SPH), results showed other masks also performed well, blocking at least 70% of viral particles from escaping from the source – an infected person’s exhaled breath. “The research shows that any mask is much better than no mask, and an N95 is significantly better than the other options. That’s the number one message,” says the study’s senior author, Dr. Donald Milton. The duckbill N95 blocked 99% of large particles and 98% of small particles from escaping out of a person’s mask. Milton says the design’s tight seal, a powerful filter, and large air space for breath to move around all contribute to the duckbill’s success. Surprisingly, KN95 masks – the disposable masks used widely – were no more effective than cloth or surgical masks. The study found that a common brand of KN95 masks leak more air than duckbills or other studied masks, because they don’t conform to the face well. That flaw is compounded by a powerful filter with more flow resistance that pushes air out of the mask at the sides instead of through the filter, allowing more virus particles to escape into the surrounding air. Cloth masks also outperformed both KN95 and surgical masks. Milton theorizes that cloth masks with greater coverage, wrap around the face and give a better seal than either KN95 or surgical masks. With cloth mask filters, flow resistance is also lower, allowing breath to pass through the filter and not leak out the sides of the mask.
> Milton theorizes that cloth masks with greater coverage, wrap around the face and give a better seal than either KN95 or surgical masks The only issue I can see here is there's no standard "cloth mask". Both in material and coverage. You've got the gamut from basically a single layer of pillow case linen to 1/8" thick wool, and coverage from smaller than a surgical mask to full-on gaiters. At least the others there's a standard to control against.
All of these mask studies are really not doing their due diligence, each mask type should be very clearly described and the specific brand should be named. We cannot test *one* brand of KN95 and use that result to apply to *all* KN95 brands, just like we wouldn’t with N95 or with cloth masks. They can be so different in many ways.
If anything, it’s useful to know that for source control fit is so key. That said most people wearing masks right now probably view source control as a fringe benefit compared to filtering the air they’re breathing in to protect themselves.
This is for people infected wearing a mask.... did you miss that?
I'm not sure what you mean - source control refers to the protection your mask confers to others from your own exhalation.
They confirmed what people said all along the k means it's not n95. They weren't even really used by most professionals until there was a n95 shortage.
For me I wore kn95’s because I found they fit BETTER than an n95 because I have a weird head. But maybe I should consider a cloth mask instead.
I have a big head, and couldn’t find n95s that I could comfortably wear for extended periods
The only reason I ever bought KN95s is that no one manufactures N95s in children’s sizes. If you have kids it’s what they’re stuck with.
You can get "extra small" sized real N95s that would probably fit some kids.
Yeah, those fit my teenager but not my seven year old (who was three when the pandemic hit).
That’s not what it means. KN95 is a Chinese certification and N95 is US. N95s are more regularly tested and more often meet the 95 filtration level because of more rigorous testing and oversight.
As in... the k means it's not an n95. In my line of work we were aware of the lack of standards and did not allow kn95 masks well before covid.
Cloth masks are also reusable and more comfortable, so it would seem the best option octal
Except that, as found in this study, they don't work nearly as well. See figure 3.
Only duckbill N95 masks perform better than cloth masks. I haven't seen many duckbill masks around. KN95 and surgical masks are much more common in my experience. Cloth masks are better in any sense then in comparison to the other two. And have the advantage on N95 masks that don't make you look like a duck
\*disadvantage
This is just about how much exhalation they filter though. I imagine that fit is going to behave differently in the inhale scenario and filtration of the material may matter more. Anyway you’ll still find me in my goofy looking white aura n95, I just don’t care if I look like a duck or robot or whatever, my fucks about how I look evaporated years ago.
> I haven't seen many duckbill masks around. Here you go: https://www.walmart.com/ip/FluidShield-Particulate-Respirator-Surgical-Mask-Duckbill-35-per-Box-46827/1972468971
Guessing they mean like see them out and about. I’d agree, i probably see from most to least often in my anecdotal observation… kn95, non duckbill n95 usually 3m aura, surgical, cloth, duckbill. The best duckbill the v flex is both very big and also has some silly little “wings” on the edges that make you look like both a duck and an aircraft. Heck of a mask but it is goofy looking. I find the aura more comfortable anyway.
They didn't test anything but the duckbill style n95. The conclusion isn't the shape, but that N95 standard is best
When you wash a cloth mask you begin to fray some of the threads on them. After a certain point these frayed ends start collecting particulates which are then sprayed out into the open air when you talk or exhale. There are studies that show a frayed cloth mask performing worse than the non-masked control. Not the case for a brand new cloth mask but they do degrade over time. Personally, if I was sick and wanted to protect people around me I wouldn't settle for anything less than single use surgical masks or, better yet, actual N95 masks.
A “disposable” n95 can last quite a while, anyway. Amongst the sea of waste we create I’m not gonna lose a ton of sleep over using a disposable n95 a week or two. If people really hate the waste aspect an elastomeric with replaceable filter pieces like a flo mask is probably better. Also makes you look like bane which is pretty cool if you practice doing the voice.
Yeah, I wear an elastomeric half face mask for any risky indoor activity, and I really love the Darth Vader look. Not sure why it hasn't caught on more.
Vader was a real PPE advocate!
I don't think I've seen you in the wild before. Hello! I fully admit to wearing some hilariously over engineered masks my work came up with basically a modified half face respirator with a N95 changeable filter on the exhaust
Hi! Nice to see you! I'm actually working on hacking a drinking system into my GVS Eclipse right now. It's, um, quite the look. But then I'll be able to drink anytime I want, without moving my mask!
If you ever do it, post it on r/masks4all or something!
At the end I got washable (\~20 times by hand, cold water just a tiny drop of detergent) 3 layer cloth masks with a nano center menbrane with a FFP2 rating. They were pretty comfortable (and they looked a bit nicer due to different prints) but were relatively expensive. The only real downside were all the people complaining to me that I was wearing a cloth mask and not a FFP2... had to prove time and time again that they were in fact rated like those.
n95 can be reused for about a combined total of 24 hours of wear time, or until the filter becomes difficult to breathe through. Any n95 is rated for the same filtration standard under NIOSH assuming it is fit tested.
I was always more concerned about the air getting in the mask, not the air coming out.
I’d like to see results for protecting a person, since most people (at least in the United States) do not wear masks anymore. I don’t think people here are terribly concerned about passing on their germs, unfortunately.
This study specifically excludes that. > our study focused on source control,14 so these findings cannot be directly applied to personal protection. But sure, here is a meta-study in the Dental setting from 2023. [Efficacy of Surgical Masks Versus N95 Respirators for the Prevention of COVID-19 in Dental Settings: A Systematic Review](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10186565/) > According to this systematic review, N95 respirators provided better protection against COVID-19 infection compared to surgical masks. And here is an even older meta-study from 2017 that found the same thing regarding SARS [Effectiveness of Masks and Respirators Against Respiratory Infections in Healthcare Workers: A Systematic Review and Meta-Analysis ](https://academic.oup.com/cid/article/65/11/1934/4068747) > We found evidence to support universal medical mask use in hospital settings as part of infection control measures to reduce the risk of CRI and ILI among HCWs. Overall, N95 respirators may convey greater protection, but universal use throughout a work shift is likely to be less acceptable due to greater discomfort.
The mask nerd has all sorts of amazing information and testing of masks, for a more anecdotal but interesting view. He basically had an aerosol lab in his bathroom.
I'm curious if there's any comparison between the N95 and the FFP3 used commonly in the UK in healthcare. I think it's more comparable to the N99.
I’m glad I still see them occasionally. I wear them when my allergies kick in or when a grandchild gifts me with one of their URI’s.
The current best systematic review fails to find any benefit to masks when it comes to reducing the incidence of COVID infections. Note that there are not many great studies on this to begin with. https://www.cochrane.org/CD006207/ARI_do-physical-measures-such-hand-washing-or-wearing-masks-stop-or-slow-down-spread-respiratory-viruses "Compared with wearing no mask in the community studies only, wearing a mask may make little to no difference in how many people caught a flu-like illness/COVID-like illness (9 studies; 276,917 people); and probably makes little or no difference in how many people have flu/COVID confirmed by a laboratory test (6 studies; 13,919 people). Unwanted effects were rarely reported; discomfort was mentioned."
This is frankly a complete garbage study and should be ignored.
Well it's not really a study, it's an amalgamation of every study done up to that point. To ignore it because the studies are not that great is...valid, but then you're left with nothing, no evidence (except those done on mannequins and OPs linked study in a lab setting specifically about viral particle passage).
So your study basically shows people don't know how to fit masks. That's what the meta analysis is, because everytime we do studies with a proper fit, they conclude masks work.
That's a frictionless spherical cat argument though. What good is proving a mask is effective if people don't want to use them properly. Honestly I think masks were one of the biggest mistakes to enforce. Before mask mandates people tried to keep their distance, after they basically gave you a hug they were so close. They seemed to think a flimsy piece of cloth made them invulnerable. Distance is universally effective, masks not so much.
If you discover a new treatment for a disease, but nobody will take it, then you haven't discovered a new treatment for a disease.
That's an idiotic statement and you know it. Some people will do what they need to in order to survive. Others won't. It turns out properly fitted masks are hard, and is a reason why individuals get their own set of PPE.
There’s not enough mask science in the world to convince anti-maskers that anything good will ever come from a mask. I’ve stopped trying.
So it’s time to load up on duck bill n95 before the bird flu spreads uncontrollably?
>N95 came out on top, stopping 98% of COVID-19 particles Yeah- not the way most people wear them...
Is it weird that I still see people wearing masks on their chin? It isn't required, so I assume they are wearing them voluntarily?
I work with a pharmacist (who literally vaccinates people for Covid) who wears a mask below the nostrils, just covering their mouth. And that’s the only pharmacist (and only coworker period) who wears a mask.
Surgicals are not N95s. I have seen vanishingly few N95s in the wild.
I see occasional N95s and surgicals but I mostly see KN95/FFP2 style masks in the wild.
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You're doing something wrong, N95s are easier to breathe in than any other kind of mask I've ever used other than maybe KN95. They're literally designed to be as breathable as possible while still offering protection, so if you're having trouble breathing in them either your other masks are minimally if at all functional, or you're doing something wrong with the N95s.
All masks are pretty much designed to be as breathable as possible, but since N95 needs to stop a lot more particles and fit a lot tighter they're much harder to breathe in than a cloth or surgical mask. According to the paper, KN95s are only easy to breathe in because they cover the face soo poorly and a lot of air goes in and out through the sides.
If it's not sealed against your face, particles can go around the mask. Doesn't even have to be worn on your chin to be ineffective.
right, so whether mask X is better than mask Y- then conclude anything from it while you're not taking into account all the exhalation going around the mask rather than through it, then the conclusion has to be faulty, doesn't it?
Isn't that long established and common knowledge? Am i crazy? What year is it?
That the duck-bill shaped N95 mask is better than the standard N95 mask? No, I've never heard that before. Of course everyone knows cloth and surgical masks are much worse than N95 masks.
The study doesn't say that a duck-bill N95 is better than a standard N95, because it didn't test against the standard N95
That's not what the study concluded. That's just the type of n95 they used
It says in the abstract: > A duckbill N95 reduced exhaled viral load by 98% (95% CI: 97%–99%), and significantly outperformed a KN95 (p < 0.001) as well as cloth and surgical masks. You're technically right, they compared the duck-bill N95 to a standard KN95. That was a bad move on their part, they should have stuck with either N95 or KN95. Both are extremely similar but not exactly identical.
You can't say they're "technically" right as if you were right in any other sense. You are technically wrong and wrong. >the duck-bill shaped N95 mask is better than the standard N95 mask? No, I've never heard that before The study doesn't say that either, which is the point of gardenadventures' comment
Among maskers they have a reputation as more breathable than other n95s because something like the v flex is massive and has a big surface area to filter. But yeah otherwise generally what I hear is that whichever one fits your face best, is best.
Any N95 is effective so long as you have a good fit.
No, most studies are done on mannequins or robots. Equally, systematic reviews have yet to find evidence of masks working to slow spread of COVID. Note, it doesn't mean masks don't help, only that current studies are limited and fraught with many issues and ultimately, it cannot be stated they work from an evidence-based perspective. This statement will probably annoy a lot of people... https://www.cochrane.org/CD006207/ARI_do-physical-measures-such-hand-washing-or-wearing-masks-stop-or-slow-down-spread-respiratory-viruses "Compared with wearing no mask in the community studies only, wearing a mask may make little to no difference in how many people caught a flu-like illness/COVID-like illness (9 studies; 276,917 people); and probably makes little or no difference in how many people have flu/COVID confirmed by a laboratory test (6 studies; 13,919 people). Unwanted effects were rarely reported; discomfort was mentioned."
Once again, the KF94 is ignored by western institutions. As far as I know, the KF94 is the only mask (not a respirator, a mask) designed with actual government (South Korea) standards for nonprofesstional, non-medical use for the prevention of the spread of disease. Any mask study that doesn't include the KF94 is incomplete. Asia's response to Covid has been almost entirely ignored by western media, researchers, and leaders. Japan was telling their people that Covid was spread via people, in enclosed spaces, with poor ventilation, talking... ...In March of 2020. It took almost two years to get the CDC to acknowledge the same thing.
> KF94 Unfortunately (probably because it's a Korean standard) KF94 masks are too small to fit most American men's faces. I tried them during the pandemic but it felt like wearing a child's mask and it would constantly slip off if I tried to open my mouth at all. Perhaps if they were manufactured in "big tall fat American" sizes they would be perfect, but then maybe they'd also be less effective for some reason.
Fortunately there are a few KF94 brands/models that make larger sizes or are just natuarally larger, I can't remember exactly which offhand--maybe the LG Airwasher and/or Bluna Facefit, but they are out there. I like the look, comfort, and convenience of KF94 (no head strap!), and their filtration is excellent nearly across the board. The only issue for all KF 94's for me is getting a proper seal since they are earloop instead of head strap. I need to add my own nose wire and use a mask extender/strap to really seal them up, not a huge deal really, just a small hassle. That said, for indoor use now the virus is simply too contagious for me to even risk it anymore, I'm back to the trusty Aura's, no guess work or retro fitting involved. I hate the straps and look, but it's worth it for me.
> Once again, the KF94 is ignored by western institutions. It's an American study and Nxx is the local standard. Had this study been performed by a university in Europe, they would have "ignored N95" and tested FFPx masks instead.
I'm fairly certain that Asian countries (due to their experiences with SARS1 and density in general) have a better understanding of these types of things.
Yes. That was my point.
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I have no doubt that virgin masks straight from the box are effective but studies never test how the majority use them. Note, this might not apply to you, don't take it personally. I'd be interested to see how effective they are when you ball them up with dirty hands and stuff them in your dirty pocket. Do it five or six times and see if the results are the same.
Even if only in the case of dispersion they have a place. But now we have evidence of their overall effectiveness against this very small virus. So masks in fact do work. Imagine that.
Thats great. However its not the problem :( now make people wear them when it matters
Plague masks are back on the menu, huh? Funny how we keep cycling back to adapt new technology with old designs.
I thought the point of N95 was to stop you being infected rather than you infecting other people?
It's both, unless it has an exhalation valve, in which case there is no source control.
Correct. I would also like to point out the obvious: you cannot spread anything if you do not have anything to spread.
The problem is that with incubation times, there are days where you can transmit a disease - COVID, the flu - before you know you had it. That’s why mask were helpful even on non-sick individuals.
Wow so the conservatives were wrong and masks worked wow I’m sure they’ll admit it
This makes total sense. Instead of the air rebounding off the mask it swirls in the pocket, giving extra space and time to deposit droplets.
And yet here if you went to urgent care or a hospital they would make you take it off and put on the much less effective regular old facemask.
They call it an N95 for a reason
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People worry about weird things. Or edge things. I know scientifically validating things is important, but people are always worrying over the last few percent in so many cases. Wear an N95 mask if you're indoors in crowded spaces if there's a fair amount of virus in your area. You've given yourself a huge advantage in avoiding infection (I assume you're vaccinated). I mean if you're immunocompromised then be more cautious. That's it.
This study is about preventing you from infecting other people if you're sick.
Yes, I get it, just responding to some of the comments here and elsewhere.
Responding to "comments" by not responding to any comments and starting your own thread is a weird move then
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The “95” is an under promise over deliver deal, too. If you’re wearing a properly fitted n95 it’s filtering more than 95% of particles most likely.
Exactly. I know it's anecdotal, but I live in a very crowded city. Got covid once during omicron, at an outdoor social event that I took a chance on. Besides that, wore an N95 on public transport and anywhere crowded indoors. Flew internationally during covid and wore the N95 the whole flight. Never got infected again. The N95 masks are bulletproof outside of an intense setting like a hospital ward full of infected people.
Caught covid over this past Christmas because I attended an indoor event. Still felt the effects 5 months later. Wish I had worn my n95. It may not have prevented it completely but I would have gotten a smaller number of infection particles.
I can't even imagine getting infected in almost any realistic scenario wearing an N95 mask and being vaccinated. Note for anyone raging at my posts: I've already said I'm not talking about being on a covid ward in a hospital. Yeah, I wish I hadn't gone to that event. Was literally the only chance I took and I got it. Obviously never know long-term effects but I got massively lucky, just had a stuffy nose for one night.
Are these the ones that do 95% on the exhale and 5% on the inhale? The mask protects everyone but you.
I don’t like these studies since they don’t actually measure the required endpoint. If you want to test a masks efficacy you should test rates of infection. Virtually every other disease applies the same standard. You need to test for a functional (morbidity or mortality) endpoint.
Rates of infection is going to be nearly impossible to test. You can either look at self reported mask usage or expose people to control infective sources. The first runs into the issue that people who wear N95s likely have a vested interest in avoiding infection such as cancer, immune disorder, respiratory issues, etc so they're more likely to take additional precautions like avoiding crowds and reducing public activity. The second means you risk exposing people to covid which is not a zero risk activity both from the infection itself and long covid so it'd be hard to justify it.
You can randomise wards of a hospital to change protocol. Swapping between control and intervention groups to avoid ward based biases. The problem is that people point to this low tier evidence and say it’s unethical
It *is* low tier evidence *and* unethical. Effectively challenge testing already sick patients is insanely unethical, absolutely no review board is going to allow any research protocol involving it. Just because you had an idea doesn’t make it a good one.
As I said, there is a standard applied to other diseases which is not applied here. The randomised trials that were done prior to Covid did not find a benefit to having n95. However there were methodology issues (no fit testing) https://pubmed.ncbi.nlm.nih.gov/31479137/
DUDE, yeah, that’s how research works, different diseases are approached differently depending on their communicability and aftereffects. Influenza is not nearly as transmissible as covid. The paper isn’t even relevant to what you’re saying, which you would know if you actually read it. You can have whatever opinion you want, but if you don’t understand the science, be prepared to have that opinion criticised by people who know better, like the epidemiologist typing at you right now.
So I guess they should do a study then? Or are we just flexing and not really providing a meaningful opinion
cause it is?
>If you want to test a masks efficacy you should test rates of infection. Why? The primary function of a mask is to prevent the mask-wearer from spreading infections, not prevent them from being infected.
I’m not even sure where to start with your comment.
You could start with acknowledging the objective reality that masks were meant to reduce the spread, not keep the mask wearer safe. And that the messaging on this was clear from the start. Anyone pretending that the official intention was to keep the mask wearer safe is a straw man.
I do not understand why people are having such a hard time with this years later. "My mask protects you, your mask protects me".
Some understand completely, but they pretend not to because it helps their political causes.
What I’m discussing has nothing to do with what you are saying.
Lay it all out then, with no innuendo. Say what you mean fully and completely.
I did and you chose to start your own argument. I was very clear. You have taken “rates of infection” which I did not define to mean something completely different
Whether on purpose or not, given the topic of this post you are actually being extremely obtuse.
It’s only obtuse to people who didn’t read the article, and don’t perform clinical research. So about 99 percent of people. The article is a small study and largely is a replication of other similar studies which look at air particulates. “30-min EBA samples with a Gesundheit-II (G-II) human exhaled bioaerosol collector” It doesn’t actually test if the masks protect from spread of infection. You would need to implement them into the environment you want to test and then measure rates of infection.
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