6 ms·

https://chrisbillington.net/COVID_VIC.html https://chrisbillington.net/COVID_VIC.html This is real world data (more relevant than any study) from Victoria wher

by flukus 6y ago

https://chrisbillington.net/COVID_VIC.html https://chrisbillington.net/COVID_VIC.html This is real world data (more relevant than any study) from Victoria where a mandatory mask mandate for anyone outside their home was abruptly introduced, it's the orange and red stripes toward then end of July. You can can see a very clear reduction with the reproduction rate of the virus shortly after the mandate was introduced. The full effect of masks is probably greater than shown because we were in lockdown at the time, so not a lot of people on public transport. They certainly aren't a magic barrier, but they do help.

__blockcipher__ 6y ago
You are assuming causality here. You can't know that with associative studies. All epidemics follow a natural curve where the pathogen initially spreads exponentially, but slows down over time as R(t) decreases due to the increased presence of population immunity. That creates a natural drop-off, and given that mandates and other "public health" responses tend to occur late in the cycle, it gives the impression that the natural drop-off is attributable to the intervention. It's rarely the case that it truly is. (By the way, if you look when they reverted to orange and then yellow the spread did not pick back up, which supports what I'm saying about this just being the natural epidemic curve) If we want to talk masks specifically, the evidence that outdoors transmission of COVID-19 is rare anyway, and furthermore the purported mechanism of action of masks only works if (a) large respiratory droplets are the primary transmission mechanism as supposed to aerosol spread, and (b) people follow rigorous protocols to avoid contamination of the mask or from the mask. (b) is certainly not true, and (a) is likely not true when you look at the overall evidence of how viral spread (and specifically SARS-CoV-2) spread occurs. Indeed, if the primary transmission mechanism is aerosol, masking could and likely would worsen transmission. The logic is pretty simple: masked individuals breathe more deeply to get the same amount of oxygen as an unmasked individual (this has been shown in numerous studies due to the local co2 buildup), meaning masked individuals move a greater net volume of air. Given masks cannot filter out aerosols, that greater volume of air will translate to worsened spread. This is made worse by the fact that when speaking to another individual, you have to speak louder for them to hear you through the mask. (Sticking with the aerosol reasoning, there is one possible tiny benefit which is the masks still do alter the path of the aerosol; it smokes out and around the mask wearer rather than it being as directed as unmasked aerosol. But it's a very minor effect at best. You can look at any of the many videos of someone hitting a vape and then exhaling out of their cloth mask/surgical mask/bandana and you'll see what I mean) So, in conclusion, no it's really not as simple as you're alleging, and this type of tenuous speculative post hoc ergo propter hoc reasoning is all too common these days unfortunately.
- flukus 6y ago
  > All epidemics follow a natural curve where the pathogen initially spreads exponentially, but slows down over time as R(t) decreases due to the increased presence of population immunity. We were absolutely no where near this point, we have one of the lowest infection rates in the world and other interventions (lockdowns) had happened weeks earlier. > If we want to talk masks specifically, given the evidence that outdoors transmission of COVID-19 is rare anyway Outdoor transmission may be rare, but this was a political decision so we could get to near 100% conformity > and (b) people follow rigorous protocols to avoid contamination of the mask or from the mask. (b) is certainly not true On the contrary, I just posted real world data that clearly demonstrates that mask discipline isn't very important. Maybe it's important under lab conditions but in the real world it's not. > Indeed, if the primary transmission mechanism is aerosol, masking could and likely would worsen transmission. So why did the reproduction rate fall and not rise after masks were introduced?
henrikschroder 6y ago
1) I'm sure the people in Victoria did a lot more things than wear masks. If you throw everything and the kitchen sink at a problem, it's very hard to figure out which of the things you did actually worked. The closest thing I've seen to a controlled study was a Danish one that showed that wearing a mask - everything else equal - reduces your risk of getting it from 2.1% to 1.8%, which is a weak 20% reduction. No study on the efficacy of preventing spread to others. (It's a bit problematic to perform an experiment like this in a controlled setting to say the least.) I'm sure masks do something, and mask mandates hopefully have a net positive effect, but how large is it? I have no idea. 2) I live in Hawaii which is also an isolated island in the Pacific, and it has a case curve that looks like this: https://www.worldometers.info/coronavirus/usa/hawaii/ https://www.worldometers.info/coronavirus/usa/hawaii/ The mask mandate went into effect on April 16th, and there's just zero correlation between that and the case curve. It's two weeks after the peak of the initial bump in cases, and apparently the mask mandate and obligatory quarantine for all incoming travelers and everything else in the emergency orders did nothing to stop the much larger peak in July-August. It's also not the case that people have been slacking off, mask compliance is very high.
- flukus 6y ago
  > 1) I'm sure the people in Victoria did a lot more things than wear masks. If you throw everything and the kitchen sink at a problem, it's very hard to figure out which of the things you did actually worked. We were. But this was the only significant change during this period until stage 4 of lockdown started which reduced the reproductive rate further. We clearly see the reproduction rate drop just after mandatory masks were introduced, in the absence of a better or even half plausible explanation it certainly looks like masks were the cause. > The mask mandate went into effect on April 16th, and there's just zero correlation between that and the case curve. As I said, they aren't magic, they won't stop the virus by themselves. You can't just wear masks and go about life as normal, but that does not mean that masks don't work at all.
  - henrikschroder 6y ago
    > But this was the only significant change during this period No, there's a very noticeable drop in social mobility as well in mid-July according to: https://covid19.apple.com/mobility https://covid19.apple.com/mobility How do you know which change had the largest effect? Also, if you introduce a mask mandate, people will obviously change their behaviour, they won't just go on and live their lives exactly as before, but with a mask on. Therefore, mask mandates might reduce the spread not because of the masks themselves, but because they cause people to behave differently. > You can't just wear masks and go about life as normal Right, and that's exactly my point, you have no idea how much mask mandates contributes to minimizing spread because it always happen in conjunction with a ton of other restrictions and behaviour changes. Yet you are arguing that masks - in isolation - are so good that it's a no-brainer to mandate them?
mssundaram 6y ago
That's hardly scientific though. You can't say with such certainty that masks caused that reduction - in the simplested terms there are too many uncontrolled variables. As one example - was the rate of testing over that time the same? You also share that there were lockdowns during that time, which would obscure the true effect of the masks.
- flukus 6y ago
  > You can't say with such certainty that masks caused that reduction - in the simplested terms there are too many uncontrolled variables. There really aren't. This was the only major change in that period for 6 million people. > As one example - was the rate of testing over that time the same? More or less (https://covidlive.com.au/report/daily-tests/vic https://covidlive.com.au/report/daily-tests/vic). The positivity rate was also quite high during that period, likely obscuring the full effect that masks have. > That's hardly scientific though. It's better. What happens in a petri dish doesn't always translate to what happens in the real world.
  - tertius 6y ago
    > It's better. No, you misunderstand. Making a claim that the data shows your conclusion to be true is what is not scientific. I.e. your statement is not based on any scientific evidence whether you think it is or not. It's just an unproven statement.

by flukus 6y ago

__blockcipher__ 6y ago

You are assuming causality here. You can't know that with associative studies. All epidemics follow a natural curve where the pathogen initially spreads exponentially, but slows down over time as R(t) decreases due to the increased presence of population immunity. That creates a natural drop-off, and given that mandates and other "public health" responses tend to occur late in the cycle, it gives the impression that the natural drop-off is attributable to the intervention. It's rarely the case that it truly is. (By the way, if you look when they reverted to orange and then yellow the spread did not pick back up, which supports what I'm saying about this just being the natural epidemic curve) If we want to talk masks specifically, the evidence that outdoors transmission of COVID-19 is rare anyway, and furthermore the purported mechanism of action of masks only works if (a) large respiratory droplets are the primary transmission mechanism as supposed to aerosol spread, and (b) people follow rigorous protocols to avoid contamination of the mask or from the mask. (b) is certainly not true, and (a) is likely not true when you look at the overall evidence of how viral spread (and specifically SARS-CoV-2) spread occurs. Indeed, if the primary transmission mechanism is aerosol, masking could and likely would worsen transmission. The logic is pretty simple: masked individuals breathe more deeply to get the same amount of oxygen as an unmasked individual (this has been shown in numerous studies due to the local co2 buildup), meaning masked individuals move a greater net volume of air. Given masks cannot filter out aerosols, that greater volume of air will translate to worsened spread. This is made worse by the fact that when speaking to another individual, you have to speak louder for them to hear you through the mask. (Sticking with the aerosol reasoning, there is one possible tiny benefit which is the masks still do alter the path of the aerosol; it smokes out and around the mask wearer rather than it being as directed as unmasked aerosol. But it's a very minor effect at best. You can look at any of the many videos of someone hitting a vape and then exhaling out of their cloth mask/surgical mask/bandana and you'll see what I mean) So, in conclusion, no it's really not as simple as you're alleging, and this type of tenuous speculative post hoc ergo propter hoc reasoning is all too common these days unfortunately.

flukus 6y ago
> All epidemics follow a natural curve where the pathogen initially spreads exponentially, but slows down over time as R(t) decreases due to the increased presence of population immunity. We were absolutely no where near this point, we have one of the lowest infection rates in the world and other interventions (lockdowns) had happened weeks earlier. > If we want to talk masks specifically, given the evidence that outdoors transmission of COVID-19 is rare anyway Outdoor transmission may be rare, but this was a political decision so we could get to near 100% conformity > and (b) people follow rigorous protocols to avoid contamination of the mask or from the mask. (b) is certainly not true On the contrary, I just posted real world data that clearly demonstrates that mask discipline isn't very important. Maybe it's important under lab conditions but in the real world it's not. > Indeed, if the primary transmission mechanism is aerosol, masking could and likely would worsen transmission. So why did the reproduction rate fall and not rise after masks were introduced?

henrikschroder 6y ago

1) I'm sure the people in Victoria did a lot more things than wear masks. If you throw everything and the kitchen sink at a problem, it's very hard to figure out which of the things you did actually worked. The closest thing I've seen to a controlled study was a Danish one that showed that wearing a mask - everything else equal - reduces your risk of getting it from 2.1% to 1.8%, which is a weak 20% reduction. No study on the efficacy of preventing spread to others. (It's a bit problematic to perform an experiment like this in a controlled setting to say the least.) I'm sure masks do something, and mask mandates hopefully have a net positive effect, but how large is it? I have no idea. 2) I live in Hawaii which is also an isolated island in the Pacific, and it has a case curve that looks like this: https://www.worldometers.info/coronavirus/usa/hawaii/ https://www.worldometers.info/coronavirus/usa/hawaii/ The mask mandate went into effect on April 16th, and there's just zero correlation between that and the case curve. It's two weeks after the peak of the initial bump in cases, and apparently the mask mandate and obligatory quarantine for all incoming travelers and everything else in the emergency orders did nothing to stop the much larger peak in July-August. It's also not the case that people have been slacking off, mask compliance is very high.

flukus 6y ago
> 1) I'm sure the people in Victoria did a lot more things than wear masks. If you throw everything and the kitchen sink at a problem, it's very hard to figure out which of the things you did actually worked. We were. But this was the only significant change during this period until stage 4 of lockdown started which reduced the reproductive rate further. We clearly see the reproduction rate drop just after mandatory masks were introduced, in the absence of a better or even half plausible explanation it certainly looks like masks were the cause. > The mask mandate went into effect on April 16th, and there's just zero correlation between that and the case curve. As I said, they aren't magic, they won't stop the virus by themselves. You can't just wear masks and go about life as normal, but that does not mean that masks don't work at all.
- henrikschroder 6y ago
  > But this was the only significant change during this period No, there's a very noticeable drop in social mobility as well in mid-July according to: https://covid19.apple.com/mobility https://covid19.apple.com/mobility How do you know which change had the largest effect? Also, if you introduce a mask mandate, people will obviously change their behaviour, they won't just go on and live their lives exactly as before, but with a mask on. Therefore, mask mandates might reduce the spread not because of the masks themselves, but because they cause people to behave differently. > You can't just wear masks and go about life as normal Right, and that's exactly my point, you have no idea how much mask mandates contributes to minimizing spread because it always happen in conjunction with a ton of other restrictions and behaviour changes. Yet you are arguing that masks - in isolation - are so good that it's a no-brainer to mandate them?

mssundaram 6y ago

That's hardly scientific though. You can't say with such certainty that masks caused that reduction - in the simplested terms there are too many uncontrolled variables. As one example - was the rate of testing over that time the same? You also share that there were lockdowns during that time, which would obscure the true effect of the masks.

flukus 6y ago
> You can't say with such certainty that masks caused that reduction - in the simplested terms there are too many uncontrolled variables. There really aren't. This was the only major change in that period for 6 million people. > As one example - was the rate of testing over that time the same? More or less (https://covidlive.com.au/report/daily-tests/vic https://covidlive.com.au/report/daily-tests/vic). The positivity rate was also quite high during that period, likely obscuring the full effect that masks have. > That's hardly scientific though. It's better. What happens in a petri dish doesn't always translate to what happens in the real world.
- tertius 6y ago
  > It's better. No, you misunderstand. Making a claim that the data shows your conclusion to be true is what is not scientific. I.e. your statement is not based on any scientific evidence whether you think it is or not. It's just an unproven statement.