3 ms·

Is this accurate?

elmerfud 6y ago
I can't comment if his paper is accurate without investigation of all the citations. In general masks are meant to stop larger particulates than what viruses are, that includes the n95 masks. Also medical masks and shields are intended to protect the wearer more than they are too prevent the wearer from spreading their infection. Breathing out puts positive pressure behind the mask causing it to bypass any filtering effect of the mask. Cloth masks are a complete joke as far as preventing spread unless you're someone who constantly sprays spittle when they talk. If you are that person then no one wants to be in spray range already . Cloth masks will barely filter dust out. The anecdotal story I share about the masks being more about a social construct than a medical one is this. My wife works in reception at a medical office. They started requiring all staff to wear makes but those in non-paitent facing roles (like her) only get cloth masks. They acknowledged that the cloth masks did nothing to prevent the spread but it was important to make masks socially acceptable. The papers closing does seem to have the conspiracy angle to it which I can't comment on if this is the case or not but overall there does seem to be quite a bit of "virology theater" going on with policy making.
- d1str0 6y ago
  Cloth masks can definitely help though. They are good at one thing in particular, reducing spread and velocity of air movement from your face. If you breath, cough, or sneeze, the transmission distance is highly reduced. You still have virus escaping, but it cannot travel as far.
  - magduf 6y ago
    This is the key here, and what all these "masks don't work!" people seem to constantly miss somehow. No, masks are not 100% effective at filtration; any idiot can see that. They don't have to be 100% effective, they just need to be better than nothing, and that'll slow the spread of the disease. Keeping people from spewing germs 20 feet when they sneeze or cough is a big help in slowing this pandemic. There's a reason masks have been commonplace in Asia for many years now: they're meant to protect society, not the wearer. When someone thinks they're sick in Japan, they're supposed to wear a mask to keep everyone else from getting sick: it's good manners. It only works when lots of people are doing the same thing. Similarly, the cloth masks are actually called "surgical masks", because they're normally used in surgery. They have absolutely nothing to do with keeping the surgeon safe from the patient; they're in place to keep the patient, who has a huge gaping wound in his body, from being infected by droplets from the surgeon as the surgeon bends over the wound site, and is breathing and talking to other people.
- Zenbit_UX 6y ago
  A distinction needs to be made between what I suspect you mean when you say a "cloth mask" which is likely the equivalent of wrapping a t-shirt around your face and a pocketed cloth mask which acts as a frame for a hepa filter. I've made two hepa cloth masks using online guides (I know, I'm like an expert now /s) for my partner and I and from my testing they filter out a non-trivial amount of undesirable particles. We use a pipe cleaner to add rigidity to the upper mask and form a better seal. I've lit a cigarette right in front of my mask and been completely unable to smell it. Does this offer us 100% protection? No of course not, is it better than not wearing one? Yes, of course.
skat20phys 6y ago
My sense of the literature is that it's accurate in the limited sense that masks often don't have statistically significant effects in studies. It's maybe also accurate in the sense that the effects of masks are really being overrated, even many n95 masks. However, in many studies there's a consistent trend toward masks doing something, in the sense that measures of dispersion are attenuated with masks vs not. This paper is pretty poor in that it commits the classic statistical blunder of equating multiple nonsignificant results with overall effect size. It's very hastily put together. One of the meta-analyses cited is an example of some of these issues (Offeddu, V. et al. 2017). You can see there's few studies and the ones included result in a nonsignificant effect, but it's almost significant and in the intuitively expected direction (PPE having an effect). But then there's issue of publication biases etc. My general impression is that the truth is somewhere in between, maybe closer to what this essay is arguing in the sense that masks are much less effective than people think, but probably not actually technically correct in that masks probably have some effect.

Is this accurate?

I can't comment if his paper is accurate without investigation of all the citations. In general masks are meant to stop larger particulates than what viruses are, that includes the n95 masks. Also medical masks and shields are intended to protect the wearer more than they are too prevent the wearer from spreading their infection. Breathing out puts positive pressure behind the mask causing it to bypass any filtering effect of the mask. Cloth masks are a complete joke as far as preventing spread unless you're someone who constantly sprays spittle when they talk. If you are that person then no one wants to be in spray range already . Cloth masks will barely filter dust out. The anecdotal story I share about the masks being more about a social construct than a medical one is this. My wife works in reception at a medical office. They started requiring all staff to wear makes but those in non-paitent facing roles (like her) only get cloth masks. They acknowledged that the cloth masks did nothing to prevent the spread but it was important to make masks socially acceptable. The papers closing does seem to have the conspiracy angle to it which I can't comment on if this is the case or not but overall there does seem to be quite a bit of "virology theater" going on with policy making.

d1str0 6y ago
Cloth masks can definitely help though. They are good at one thing in particular, reducing spread and velocity of air movement from your face. If you breath, cough, or sneeze, the transmission distance is highly reduced. You still have virus escaping, but it cannot travel as far.
- magduf 6y ago
  This is the key here, and what all these "masks don't work!" people seem to constantly miss somehow. No, masks are not 100% effective at filtration; any idiot can see that. They don't have to be 100% effective, they just need to be better than nothing, and that'll slow the spread of the disease. Keeping people from spewing germs 20 feet when they sneeze or cough is a big help in slowing this pandemic. There's a reason masks have been commonplace in Asia for many years now: they're meant to protect society, not the wearer. When someone thinks they're sick in Japan, they're supposed to wear a mask to keep everyone else from getting sick: it's good manners. It only works when lots of people are doing the same thing. Similarly, the cloth masks are actually called "surgical masks", because they're normally used in surgery. They have absolutely nothing to do with keeping the surgeon safe from the patient; they're in place to keep the patient, who has a huge gaping wound in his body, from being infected by droplets from the surgeon as the surgeon bends over the wound site, and is breathing and talking to other people.
Zenbit_UX 6y ago
A distinction needs to be made between what I suspect you mean when you say a "cloth mask" which is likely the equivalent of wrapping a t-shirt around your face and a pocketed cloth mask which acts as a frame for a hepa filter. I've made two hepa cloth masks using online guides (I know, I'm like an expert now /s) for my partner and I and from my testing they filter out a non-trivial amount of undesirable particles. We use a pipe cleaner to add rigidity to the upper mask and form a better seal. I've lit a cigarette right in front of my mask and been completely unable to smell it. Does this offer us 100% protection? No of course not, is it better than not wearing one? Yes, of course.

skat20phys 6y ago

My sense of the literature is that it's accurate in the limited sense that masks often don't have statistically significant effects in studies. It's maybe also accurate in the sense that the effects of masks are really being overrated, even many n95 masks. However, in many studies there's a consistent trend toward masks doing something, in the sense that measures of dispersion are attenuated with masks vs not. This paper is pretty poor in that it commits the classic statistical blunder of equating multiple nonsignificant results with overall effect size. It's very hastily put together. One of the meta-analyses cited is an example of some of these issues (Offeddu, V. et al. 2017). You can see there's few studies and the ones included result in a nonsignificant effect, but it's almost significant and in the intuitively expected direction (PPE having an effect). But then there's issue of publication biases etc. My general impression is that the truth is somewhere in between, maybe closer to what this essay is arguing in the sense that masks are much less effective than people think, but probably not actually technically correct in that masks probably have some effect.