I still find it difficult to understand if homemade masks actually reduce, due to all the different messages out there. Even the links provided in the Google Docs (https://docs.google.com/document/d/1HLrm0pqBN_5bdyysOeoOBX4p...) are more focusing on professional masks.
I even heard an "expert" saying on national TV that non-professional masks were worse, because the virus could actually stick to it :S
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.
Not good reason. Lying to people to try to manipulate their presumed stupidity for their own good doesn't work. We went through this with the malarkey around claiming "advising abstinence is safer than offering condoms for STD protection"
Yes, but the messaging is not consistent which leads to public distrust, which might actually be worse. Don't wear masks, they don't help! But we need them because they do actually help! It's obviously not that simple but that's the way it's being perceived.
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.
I've seen no evidence that masks give people a false sense of security. If anything, it seems to be the opposite. People report that when they wear masks, people move away from them, and employers have asked them not to wear them because they might make the customers feel unsafe. They're a giant reminder that things aren't normal and that we're in the middle of a massive pandemic. This is a good thing.
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.
Non-medical masks don't keep stuff out. They just keep stuff in, so the only reason to wear it is to not spread your water droplets when you sneeze or cough. Medical masks keep stuff out, but are in short supply.
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.
I think you might have misunderstood the parent comment (since your reply is somewhat of a non sequitur). My interpretation was that "if I wear a mask, then people will assume I'm infected and give me space, which is actually just better for me regardless of the mask's direct efficacy".
This binary assertion is fairly broadly given and I think it’s a narrow view that is a subtle form of unintentional disinformation that endangers. Any reduction of viral load on exposure is by nature better. The intensity of initial viral
Old can help determine whether you get covid 19 and how strong it hits. It’s difficult to believe that some worth of cloth covering will have absolutely zero reduction of viral load. No you shouldn’t think it’s a comprehensive protection. But it’s silly to handwave away as useless as many do. Anything that limits spread should be encouraged. People still need to minimize going out, but if they have to, and have nothing else, dismissing all other masks as useless is not helpful.
I'm not so good with spreading my own potential risk around. It's essentially selfish to not wear a mask because 'it can't help me'.
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.
False - hand to nose mouth contact is THE primary vector for this illness - masks are very effective in reducing this. Please stop spreading misinformation as it could lead to deaths.
Droplets through the air is not primary vector - this is not aerosolized well like measels, the drops fall to the ground -> 6 foot rule is designed to avoid most droplets.
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.
I'd disagree with the false sense of security line. Why would someone who cares enough to go to the effort of wearing a mask then go and not wash their hands? A positive correlation between the two seems more likely than negative to me.
Also this argument is trotted out regularly by "experts" in the car manufacturing industry whenever new safety technology is invented and as far as I can tell is always proven years later to be bullshit. For examples see seat belts, air bags, traction control, ABS, AWD.
In some parts of the US like NW Washington, toilet paper is in short enough supply that some households need to put non-trivial time and effort to get some.
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.
See that the link is advocating for people to use homemade masks. They won't take way masks from health professionals. The base of the argument is that self-made masks are also useful and can help contain the virus.
It's stupid. N95 masks are in short supply and so should be reserved for healthcare workers and those caring for the infected but sugical masks can still help slow the spread. People should be weraring those in public. But the only messaging from the top is not to wear the masks
There seems to be evidence that masks can make your exposure worse by trapping some amount of air containing the virus under the mask, making you more exposed. If you are sick they can protect others around you, but if you are healthy, less so. In that context the flip of public opinion makes some sense: as we go from assuming most people are healthy to assuming most people are sick, masks for everyone in public can help.
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.
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.
I don't have any medical training, and speak only from perspective of common sense.
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.
"There seems to be evidence that masks can make your exposure worse by trapping some amount of air containing the virus under the mask, making you more exposed"
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.
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.
That's the first time I've heard about that theory about why wearing masks could be dangerous. Do you have a citation for that? I'd be very curious to read the study. Intuitively it seems like there's no way you could end up with a higher time integrated density of virions inside the mask than outside unless you put on the mask in a very contaminated area and then wore it into non-contaminated place. But maybe there's some mechanism I'm not thinking of?
Not an expert but I have never heard of this air trapping phenomenon, unless it is introduced by putting on the mask with infected hands I suppose. How would it get there in the first place?
There is evidence of efficacy in wearing even simple facemasks. Skepticism will lead your imagination to walk in circles [continuing without said mask].
I'm wondering about this myself. I mean I can understand not wanting to put pressure on the health system by adding extra supply, but homemade masks - even a bandana, must ad at least some protection.
Even if it only reduces R0 by a few procent that would mean a lot?
They recommend against it, because recommending the use of masks would expose the universal lack of availability of even basic surgical masks. The on-demand system in the US cannot cope with events like this (no stockpiles).
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.
Just a nit - mask production could have been ramped up throughout January and February, by executive order if necessary, if the virus had been acknowledged as a threat instead of simply being ignored for two months.
I even heard an "expert" saying on national TV that non-professional masks were worse, because the virus could actually stick to it :S