Masks4All: Wear a mask to stop the spread of Coronavirus (Jeremy Howard)
masks4all.co
masks4all.co
1. After breathing in a mask for a while, the outside is now "potentially contaminated" with COVID19. Treat the outside of a mask as if it were infected.
Do NOT touch the mask while using it. Do NOT rub your eyes, etc. etc. Do NOT put on the mask backwards. It is recommended to color-code the inside and outside to make it easier to see.
2. There are a ton of discussions about how to disinfect a cloth mask. Kitchen equipment is commonly recommended. Boiling the mask, letting it sit in the oven for some time, etc. etc. You only need to raise the temperature to ~212F or so (boiling) to disinfect. (maybe lower, but boiling is easy because the bubbling water serves as a temperature gauge).
There may be easier chemical treatments, such as bleach when you're washing the cloth mask. But boiling is obviously safe.
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Note that "N95" masks are only 95% effective against viruses (even if you did everything correctly). Homemade masks will probably only reach 70% or maybe as low as 50%. You aren't invulnerable, you just have a layer of protection on.
I think this "home made mask" idea is very good. We need to leave the N95 masks for professionals, because the USA has a mask shortage (and N95 masks are disposable. One-time use).
Home-made masks can be reused through washing.
Instead disinfect them with dry heat in an oven or rice cooker. https://news.ycombinator.com/item?id=22680799
Perhaps my advice is specific to repurposed T-shirt masks then. But this study boiled the masks before testing and use.
The study was designed for poorer countries without as much infrastructure. Which is why the materials are so simple and the methods crude. But those attributes are very useful for the DIY community.
There are masks that offer greater protection than N95. Among them are N99, N100, and various others. There's a good article that discusses some of the differences here: [1]
"N95 masks are disposable. One-time use"
Some types of N95 masks are disposable, others are reusable. Also, even the disposable kind could be (and have been) reused. This is, for example, widely done in hospitals where there's a short supply of masks, on the theory that some protection (even if imperfect) is better than no protection.
This protection is more than the numbers may seem. See this essay on the benefits of contracting a disease in a smaller dose:
http://www.overcomingbias.com/2020/03/variolation-may-cut-co...
> The most directly relevant data is on SARS and measles, where natural differences in doses were associated with factors of 3 and 14 in death rates, and in smallpox, where in the 1700s low “variolation” doses given on purpose cut death rates by a factor of 10 to 30.
If you can cut the dose by 70%, it gives your immune system more time to ramp up ahead of the virus, which often translates into a more controlled infection with lower level symptoms, if any.
- Stops infected people [including asymptomatic] from expelling infectious particles.
- Helps remind you not to touch your face [and precludes direct touch to mouth and nose--where mucus membranes are vulnerable].
- Much better chance of a low inoculum [a smaller initial viral load results in less severe symptoms].
I like these instructional videos about how to put masks on and take them off, because they emphasize that you should be washing your hands when you put the masks on and take them off.
How to Put on a Surgical Mask: https://www.youtube.com/watch?v=jWnTCZWYOBw
N95 3M mask: How to Wear & Remove: https://www.youtube.com/watch?v=zoxpvDVo_NI
The mask won't do as much good if you just end up transferring the virus to your face after taking it off.
NNTaleb: Asymmetry: error FROM NOT wearing masks is vastly costlier than the error FROM wearing masks.
https://twitter.com/nntaleb/status/1244976894686179328?s=21
EDIT- I think I wasn’t clear— mask is critical protection, and the risk of infection from wearing one incorrectly is far lower than not having one at all. I was just responding to the final paragraph that the mask doesn’t do much good if transferred from mask to mouth during removal— very true, but it also reduces the quantity of the virus ingested.
On the contrary. The virus is on the mask. That's why doctors / nurses wear masks, so that the virus gets stuck in the mask instead of in the doctor.
Now that the virus is on the mask, you need to treat it as if it were a contaminated object.
Hmm, I'm not sure about this one. Going to the pharmacy today, I noticed some people wearing masks, and just in the short time I saw them, many were adjusting/fiddling with their masks.
In this attempt by the US government to stop this pandemic I found their suggestion not to wear mask the most disgenuine of all, especially knowing that countries with high mask wear awareness see this virus much more under control. In the same paragraph they already express they really need those masks for themselves so they don’t want you to hoard. Another argument was they only help when you sick. So all medical personel is sick? What a BS! Even more when they know you may be asymptomatic for up to 9 days.
The only thing I can think of equal to this would be if during HIV outbreak they were to tell you not to use condoms at all because study shows they don’t protect exact 100% times, and you can cut your member with your nail while you putting the rubber on, making it more prone to infections than when you’re actually wearing one.
Government really messed up on this one. Once the dust settles it will probably go into history books how our government suggestion not to buy/wear mask caused USA to be #1 in statistics.
I do however think that, in general, masks are more needed by healthcare workers. They are on the frontline of COVID-19, and have no choice but to get up close to infected patients - most normal people are able to practise social distancing.
If you are concerned you will infect yourself by touching your face too much, just wear a mask at home for a few days, and get over the adjustment phase in a safe environment.
> If you are healthy, you only need to wear a mask if you are taking care of a person with suspected 2019-nCoV infection.
The World Health Organization still recommends that you wear masks only if you're taking care of someone with COVID-19. Why is it so?
Like if the evidence is so clear, why aren't they advising the general public about this? (PS. non-native english speaker, ignore poor english)
[1]https://www.who.int/emergencies/diseases/novel-coronavirus-2...
Even in HN, until last week there were many articles linking to studies which said that surgical masks were not proven to reduce your chances of getting the virus.
In mid January they said that China had no evidence of human to human transmission despite Taiwan telling them otherwise, probably due to political reasons. They refused to declare a pandemic weeks after it was clear it was one, and even now they still insist on ignoring the data we have around masks.
Presumably, these doctors didn't die during last year's flu epidemic. Nor during the previous years or decades of their practice. So something is different this year. Something they normally do to protect themselves, that isn't working this year.
Hm, they use hand washing, gowns, gloves, masks. Which one, do you think?
And also, lots of doctors and nurses are coming down with Covid-19 right now despite being careful about their use of PPE.
EDIT: When people first started talking about surgical masks versus N95 respirators one study that came up was this one[1] from Ontario which showed that a bit over 20% of nurses using either of them got infected with influenza over the course of a flu season. Infections happen unless extreme care is taken as with things like Ebola.
[1] https://jamanetwork.com/journals/jama/fullarticle/184819
from: https://www.politico.com/news/2020/03/30/maryland-shelter-in...
People are still going out and doing things around and with other people. And they shouldn't be, even with a mask.
At least in France, "Wear a mask" would be understood as "wear an FFP2, surgical-level" mask. The kind of masks:
* that we are in very short supply of at the moment (for various and sad reasons)
* that we have to save for doctors
* that everybody would try to buy on black markets if you asked them to use
* that we unfortunately told people not to try and buy (precisely because we need to save them for doctors because they are in short supply, etc...)
So if a campaign started today saying "wear a mask", with the intention of saying "cover your mouth with a piece of fabric that you made yourself if you're not sick", I suspect it would be counter-productive.
We need another word.
My Argentinian wife tells me it's similar in Spanish - a mask would mean an N95 mask or similar. And a surgical mask would not be included if I understand correctly (they are not as good as N95 masks, they're mostly just a piece of fabric).
I live in Manhattan, and I still see people walking around outside with "real" masks.
> "Note: Please do not buy surgical or N95 masks because we need to keep those available for the doctors, nurses and first responders so they can stay healthy and care for the ill."
"If your mask is not made of flammable material, Lin said, you can try putting it in an oven for 30 minutes at 158 degrees Fahrenheit, because the coronavirus is fragile. Doing so can kill off the virus, and “it doesn’t destroy the mask very much,” she said, adding that hanging the mask above a pot of boiling water for about 10 minutes could also help with killing off the virus, but it would need to be air-dried afterward."
https://www.huffpost.com/entry/reuse-face-mask-coronavirus_l...
Some people bought their masks long before the mask shortage, and hospitals don't accept donations of used masks.
I know over at coquetryclothing.com they used to decline to make masks due to possible liability reasons. Now they are making custom ones with all manner of fabrics.
Normalizing masks will also help fight facial recognition. IIRC, the Chinese systems have trouble with people who are wearing a surgical mask and sunglasses. No attention-grabbing dazzle makeup required.
It sucks that we even need to think about wearing masks to escape facial recognition.
That's overly fatalistic. China hasn't banned them for that reason, and they're way more interested in that rationale than any government you're likely talking about.
> It sucks that we even need to think about wearing masks to escape facial recognition.
Avoiding facial recognition isn't just about avoiding the government facial recognition.
It's been illegal in New York since 1845, due to some kind of violent conflict between landlords and tenant farmers. Some laws were targeted at the KKK, and newer laws were targeted at Occupy and Anonymous folks wearing Guy Fawkes masks.
This article[2] has a more complete list of state laws against masks, and where they've been overturned.
[1] https://en.wikipedia.org/wiki/Anti-mask_law#United_States
[2] https://www.businessinsider.com/countries-states-where-prote...
The government did this long ago, as a reaction to the KKK wearing masks to intimidate their victims and hide their identity.
So it's actually already against the law to wear masks in public in many places in the US.
I've never heard of this law being enforced in modern times, however.
I challenge you to find an example of a blanket ban on all masks, that doesn't rely on other factors like threatening violence, rallying, intent to hide identity, or a respresenting specific gang design/color.
Otherwise you will be marginalized and the masses will be "educated" by the mass media about how evil and troublesome "you people are."
Ensuring diversity in information dissemination is absolutely key to shooting down these proposals which harm personal freedom.
A surgical mask is just a simpler cheaper, less complete and less effective mask than an N95 mask, used in lower risk situations or when N95 is desired but not available.
https://www.cdc.gov/niosh/npptl/pdfs/UnderstandDifferenceInf...
The WHO and CDC have been pushing that line as well. Studies linked to in the above article suggest that even home made masks provide some protection to healthy individuals. But even if they didn't, getting everyone to wear them would be extremely valuable for stopping the spread coming from people who don't know they have the disease. Also, "Don't come in hear unless you have something covering your face" is an easy rule for establishments to enforce, whereas "If you have Coronavirus you need to cover your face" is impossible to enforce.
Yet I've seen almost no leadership at any level in the U.S. pushing this (and this seems to be true in much of the West). Lockdowns buy us time, and we seem to be wasting that.
While I was thinking about my homemade one I thought that steam ironing is probably a good and quick way to disinfect (for those that have an iron).
Hong Kong scientists also developed and tested a few home made designs, make of them what you will.
https://www.scmp.com/news/hong-kong/health-environment/artic...
Also, don’t forget that in medical facilities N95 masks are fitted specifically to individuals. You can’t just throw one on and be protected. Most people won’t go through the trouble of doing that properly. At that point it’s like putting your shirt over your nose: looks like you are protected but there are giant gaps that let in air.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3373043/
A cut t-shirt over your nose is actually quite good, so long as the pattern is somewhat tested. No, its no where close to an N95 mask, but even aerosol sprays can be somewhat mitigated with a simple cut t-shirt.
There are some internet studies suggesting an efficacy of 70% for T-shirts against 1-micron (bacteria) and 0.02 micron (viruses) particles. That's 6x worse than an N95 mask, but much better than unprotected.
EDIT: It seems like the flu (also a 0.02 micron virus) is primarily on water-droplets 5 microns in size. So we don't actually have to reach N95 mask levels for a major amount of protection, aiming at the 5 micron sized moisture bubbles is already going to help us severely.
Where is that evidence?
"in medical facilities N95 masks are fitted specifically to individuals. You can't just throw one on and be protected. Most people won't go through the trouble of doing that properly."
Most people haven't been washing their hands properly either, and yet the government has gone to great lengths to educate people on how to properly wash their hands. There's no reason they couldn't do the same with mask fitting.
Your argument about trapping virus inside the mask is not very convincing. If you are putting a physical barrier between your respiratory system and air in high-risk areas (general stores, pharmacies and public transportation), then statistically there should be far more prevented contacts with viruses than trapped virus particles.
The incorrectly fitted masks should provide some benefit over no mask, so this doesn't seem as a good argument for not wearing masks. I would think that even putting shirt over nose gives some protection as it prevents touching face and diminishes odds of contamination with spit particles. Besides, the article is about home-made masks and not N95 masks.
The only convincing reason against masks is that they give false sense of security, so they shouldn't be the _only_ measure. Washing hands, wearing masks and physical distancing can only be beneficial.
Lets not over-dramaticize N95 masks. An N95 mask is just 95% effective. Its not N99 or N100.
N95 is the relatively cheap and disposable mask. Its "custom fit seal" is the little metal bar that you push down on your nose.
Here is 3M's official fitting video. Its actually not very hard to use: https://www.youtube.com/watch?v=05wyH1-mLGk
Then elastic bands shove the mask against your face, forming an airtight seal. This can be effectively replicated with a decent hand-made mask solution (although the filtration of a hand-made DIY mask is much much worse, and completely untested compared to N95 designs)
Given the fact that we're in an N95 mask shortage situation, I think DIY home-made masks are the only solution for the general public. It just takes some scissors and a T-Shirt to make.
Even if it only reduces R0 by a few procent that would mean a lot?
They recommend against wearing medical to help cull the shortage, and they recommend against wearing non-medical because they can provide a false sense of security, especially when worn incorrectly. Both very good reasons, IMO.
I just assume that anyone wearing a mask is doing so because they're infected, as per the recommendations, and I'm giving them a wide berth.
Another reason to wear a mask.
I think I'm helping more by going with the recommendations and not wearing a mask. Some people feel better wearing them, and that's fine too.
Further, just yesterday on HN, there was a post about how a University study of airplane travelers showed mask-wearers got both benefits - they rarely caught anything and rarely infected anyone, even with the simplest masks.
Do you have a source for this? It's contrary to most of what I've read (droplets through air is primary vector).
"In an adjusted analysis of compliant subjects, masks as a group had protective efficacy in excess of 80% against clinical influenza-like illness." -https://www.ijidonline.com/article/S1201-9712(08)01008-4/ful...
All the folks saying masks don't work literally never cite to any actual study - I think it's something like 90+ studies showing masks work and maybe 1 or 2 without a good result for masks.
> Droplets through the air is not primary vector
and
> hand to nose mouth contact is THE primary vector for this illness
In contrast, Johns Hopkins guide currently states: "Transmission - By respiratory droplets and by fomite. Virus found in respiratory secretions and saliva. - Viral shedding by asymptomatic people described, uncertain to what degree this occurs and abets transmission. - Stool shedding also described, but uncertain what role, if any, that plays." https://www.hopkinsguides.com/hopkins/view/Johns_Hopkins_ABX...
In daily living you touch door handles, gas pump handles, elevator buttons, railings, subway hang straps and bars etc. Even before covid, how many people sneezed on you? Far fewer.
If we just were worried about folks sneezing on us we could stop washing our hands.
Here's the best article I've found on transmission, and a key excerpt. http://www.cidrap.umn.edu/news-perspective/2020/03/commentar...
> In risk communication guidelines for healthcare, however, the WHO states, "COVID-19 appears to spread most easily through close contact with an infected person. When someone who has COVID-19 coughs or sneezes, small droplets are released and, if you are too close, you can breathe in the virus" (emphasis added).9 But wait: Inhalation is not part of the traditional definition of droplet transmission.
> For healthcare organizations, the CDC recommends airborne, in addition to standard (contact) and droplet precautions, for the care of COVID-19 suspected or confirmed patients.10
> For the general public, the CDC describes SARS-CoV-2 transmission as primarily by droplets from coughs or sneezes, which "land in the mouths or noses of people who are nearby or possibly inhaled into the lungs" (emphasis added).11 But, again, inhalation is a new addition to the traditional definition of droplets. In contrast to its recommendations for healthcare, the CDC makes no mention of airborne transmission in public settings.
> The CDC admits some possibility that COVID-19 may be transferred by hands to mouth, nose, or eyes from contaminated surfaces, but notes that "this is not thought to be the main way the virus spreads."11
Maybe a minority, as there will always be, but I think most people are aware of the difference between medical and non-medical masks, and feel the messaging is consistent.
If mask use becomes mandatory, will there still be groups of people standing in the middle of supermarket shouting to each other? Sure, just like there are now. The difference is those people will at least have masks on.
I even heard an "expert" saying on national TV that non-professional masks were worse, because the virus could actually stick to it :S
It's hyper local. I got lucky and hit Costco in December. Feel like I still see it in stores sometime, but people need to shop around.
Acetaminophen is trickier now.
So, they're recommending we don't use masks, so that more masks are available for medical professionals, so that when most of us get sick via community transmission (because we don't have masks), the medical professionals can also run out of masks while they treat us.
The video convinced me I shouldn't keep waiting for them to be back in stock at the store.
Two paper towels and a tissue paper actually.
The different materials lead to better filtration and absorption. The theory is to absorb the microscopic moisture that has COVID19 on it.
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I think the "cut t-shirt" design is easiest. With a bit of sewing effort, you can make it 3-ply or 5-ply for additional protection. Try to get the grains to go in different directions.
If you are infected, just use any mask. Your breath still escapes from an N95 mask's corners, spreading the virus nearby, and probably onto your hands. Sure, it won't projectile-travel as far, but it's still spilling out onto nearby surfaces/people.
In Asia, face masks have been trendy ever since the avian flu. But tons of studies showed that this had no significant effect on reducing people getting sick, because eyes, and touching face. The masks are just a psychological thing at this point.
"Historically, in a lot of health care settings there was limited attention [to eye protection], and part of droplet protection, part of being protected when someone coughs or sneezes is protecting your eyes as well. Actually, going in to this I was pretty heavy on re-education at one of the hospitals about: if someone's on droplet, you gotta protect your eyes. Because influenza, you get that in your eyes you can get infected. SARS-CoV-2, you get that in your eyes you can end up with COVID-19. So eye protection is important as well."
[1] - http://www.microbe.tv/twiv/twiv-593/ at about 1 hour and 58 minutes in to the program
See https://news.ycombinator.com/item?id=22733249
And https://news.ycombinator.com/item?id=22706216
I'm not too frustrated about this because there's a lot of confusion on mask usage, people buying masks that doctors need, etc.
https://thehill.com/homenews/administration/490308-cdc-may-u...
Edit: Here's the WHO's stance on wearing masks: https://www.who.int/emergencies/diseases/novel-coronavirus-2...
For example, "Professional and Home-Made Face Masks Reduce Exposure to Respiratory Infections among the General Population" [2]
It's also worth noting that many people with COVID-19 are asymptomatic, so wearing a mask, even a homemade one, could reduce the spread to other healthy people.
[1] https://docs.google.com/document/d/1HLrm0pqBN_5bdyysOeoOBX4p...
I think part of the issue in this case is that no one knows if they are "healthy." You could be transmitting the disease while still asymptomatic yourself.