Surgical masks aren't about protecting the wearer from everyone else, they're about protecting everyone else from the wearer [1]. They may provide the wearer some protection, but that's not really the point.
The emphasis in the rhetoric about masks needs to change. It should not be about individualist self-protection, but about doing your part to protect the community. I think they should be recommended for that reason [2].
[1] Respirators are devices for protecting the wearer, and the N95 type has been much discussed. Everyone should learn the difference to de-confuse the general conversation in this topic:
https://www.youtube.com/watch?v=JR2uLfEVD2w
https://multimedia.3m.com/mws/media/956213O/differences-betw...
[2] If there's enough supply. It seems like surgical masks are getting drafted into the role of PPE for medical personnel (which they're poorly suited to) due to the N95 shortage. It's unfortunate that the US hasn't developed a culture where you wear a mask to protect others from your illnesses, so they're not widely available outside of healthcare settings.
I think you're confusing the normal use for these masks with what they are actually capable of doing. Yes, in a surgical setting the masks are worn primarily to protect the patient from the surgeon, but the masks do work both ways. Here's a citation from an infectious disease specialist:
https://www.health.com/condition/cold-flu-sinus/surgical-mas...
>“Yes, a surgical mask can help prevent the flu,” Sherif Mossad, MD, an infectious disease specialist at the Cleveland Clinic, tells Health. “Flu is carried in air droplets, so a mask would mechanically prevent the flu virus from reaching other people.” It would work both ways, says Dr. Mossad, preventing transmission of the flu virus to others and for keeping a mask-wearer from picking up an infection.
> I think you're confusing the normal use for these masks with what they are actually capable of doing. Yes, in a surgical setting the masks are worn primarily to protect the patient from the surgeon, but the masks do work both ways. Here's a citation:
I wasn't confused. That's why I said they may provide the wearer some protection. The 3M YouTube video I linked even quantifies this, by measuring and comparing leakage between a surgical mask and an N95 respirator.
But that's not the point. Don't wear a mask to protect yourself, wear a mask to protect others.
Now we have the separate issue of the fact that there is a critical supply shortage. In such a scenario I'm more than happy to oblige in managing systemic risk by allocating all the masks to healthcare workers, the critically vulnerable, etc. But don't lie to me along the way.
Normal people using surgical masks in public are definitely also for protecting the wearer, and do offer protection.
"Any type of general mask use is likely to decrease viral exposure and infection risk on a population level, in spite of imperfect fit and imperfect adherence, personal respirators providing most protection."
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2440799/
Additionally, the number of asymptomatic carriers who may be able to spread the disease is possibly quite large.
For example, I don't trust the WHO much anymore because they lied and said that closing China's borders would not stop the spread of corona behind pressure from the Chinese government.
For medical professionals in close contact with patients and dealing with airborne-protocol pathogens (which is what a droplet-mediated pathogens like SARS2 becomes classed as once patients are coughing and being intubated) then a bad mask is quite probably worse then no mask (this has precedent: ineffective masks obstruct breathing, which makes you take deeper breaths and draw more particles in deeper in your lungs - it's a big problem when dealing with fine dusts in construction).
You’re saying you think anything less than an N95 has 0 effectiveness. Why do you believe this is likely? Are you aware of the data that says otherwise?
https://news.ycombinator.com/item?id=22655436
https://www.researchgate.net/publication/258525804_Testing_t...
https://jamanetwork.com/journals/jama/fullarticle/2749214
“As worn by health care personnel in this trial, use of N95 respirators, compared with medical masks, in the outpatient setting resulted in no significant difference in the rates of laboratory-confirmed influenza.”
To be clear, this trail was for outpatient care — not necessarily applicable to shoving tubes down throats, but probably applicable to people walking down the street.
> However, these masks would provide the wearers little protection from microorgan- isms from others persons who are infected with respiratory diseases. As a result, we would not recommend the use of homemade face masks as a method of reducing transmission of infection from aerosols.
The recommendation here is assuming you have access to something better. If you have no access to something better, a homemade mask is better than no mask at all, until you can get something better. As others have pointed out here, it’s rather odd to suggest we should scoff at this imperfect solution, when there are no perfect solutions short of 100% full and complete quarantine, which is completely unrealistic.
There's a lot of variation in influenza viruses, but most are spheroids or ellipsoids with a diameter from 80-120 mm.
For simple mechanical filtering, such as with a mask, they are going to behave pretty similar.
https://www.cdc.gov/coronavirus/2019-ncov/hcp/ppe-strategy/f...
Unfortuately, the CDC really is giving out conflicting guidance here. For example, higher up in the section for lay-people is this: “You do not need to wear a facemask unless you are caring for someone who is sick (and they are not able to wear a facemask). Facemasks may be in short supply and they should be saved for caregivers.” https://www.cdc.gov/coronavirus/2019-ncov/prepare/prevention... (In “How to Prepare | Protect Yourself”)
If you are not exposed to high levels and are not required to put yourself at risk to care for patients, you are at low risk. You can protect yourself with milder measures like social distancing and face protection that is not as effective but not in such short supply
I mean I agree, of course, that they’re trying to maximize public health benefit, I just don’t think the guidance is at all clear to the public. The idea that anything less than N95 is useless is pervasive, you can see it right here on HN. My parents and co-workers believe it because it’s been reported in the mass media in the last weeks: “the CDC said masks don’t protect you!”.
For people who need to work or shop in public places, any kind of masks at all might well be statistically significant alternatives for people who are unable to practice social distancing. China seems to be doing it effectively right now; people are required to wear masks to go to work. They’re not telling the public to avoid masks because doctors need them, they’re telling the public not to leave the house and not to enter a work building without something over your face. It seems like the CDC is saying the opposite, you should not wear a mask unless you’re a doctor. If a bandana is even 50% or 30% or even 5% effective, and they want to maximize public health benefit, why aren’t they recommending people start with what they have at home for times when public exposure is necessary? Seems like that would both increase public health and deflect demand for surgical masks & N95 masks at the same time, no?
Current CDC guidance is “facemasks are an acceptable alternative when the supply chain of respirators cannot meet the demand”.¹
¹ https://www.cdc.gov/coronavirus/2019-ncov/infection-control/...
Had to explain this to someone yesterday. They literally wouldn't believe me until I screenshotted an Excel spreadsheet of the daily doublings, despite a finance degree.
"It's a great pleasure to be here, and to have a chance just to share with you some very simple ideas about the problems we're facing. Some of these problems are local, some are national, some are global.
They're all tied together. They're tied together by arithmetic, and the arithmetic isn't very difficult. What I hope to do is, I hope to be able to convince you that the greatest shortcoming of the human race is our inability to understand the exponential function."
Most people I try to explain the current problems are really not able to understand. I explain that the spread is exponential, and that the problem is that is grows so fast. I say look at the graph from China, look at the graph from Italy.
They answer "ah, the Chinese maybe hid some numbers."
I say, it just doesn't matter, only the shape of the curve matters, and it repeats in every land. Even if the Chinese hid half of the cases, that difference disappears in only three-four days in our locations, where it grows so fast, as it grew in China before they did their measures, much harder than ours.
They don't understand still. They think only "80000 in China is more than "50000 in Italy" and it stops there. That Italy will get from 50K to 100K in four days, that's what they don't understand until they'd see it happened, but it would still, sadly, not convince them in anything.
Whereas, not only it's just the shape of the curve that matters, we know exactly why the spread is exponential, and what has to be done to change the shape: manage to stop the people who have it to transmit the virus to the rest of the population. It's "just" people who spread it -- the virus is not a bacteria, it doesn't live or multiply by itself, it needs a host which will replicate it, and the only host spreading it among the humans is human. There's nothing else that we know to work than that.
The major danger is that 4 from 5 carriers of the virus won't feel so bad to think that they should really stay at home. Most of the carriers aren't aware what they do. They all have their lives where what they do at the moment is "urgent" and "must be done." As soon as the droplets they produce enter the lungs of other people, the virus is spread. The droplets are tiny enough to be normally invisible to us, of course.
It doesn't help at all that the most of the highest politicians, across many different countries, downplayed the seriousness of the situation for a long time. Even less that the scientific ignorance was promoted as a virtue for even longer times.
Face protection must surely have the side-benefit as well that it signals to others to keep your distance and that this is a serious situation.
So yes once you've removed all non essential contact masks add another layer. But people are fairly stupid on average and need simple messages right now.