Face masks effectively limit the probability of SARS-CoV-2 transmission
science.sciencemag.org
Face masks effectively limit the probability of SARS-CoV-2 transmission
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Re: Face masks effectively limit the probability of SARS-CoV-2 transmission
#2>Surgical masks with particle collection efficiencies around ~50% cannot prevent the release of millions of particles per person and their inhalation by others (green dots in Fig. 1, B and D). In other words, the human-emitted respiratory particle number is so high that we cannot avoid inhaling particles generated by another person even when wearing a surgical mask
So the entire premise of the modeling in the paper rests on the assumption that surgical masks can filter some percentage of viral particles. It's my understanding that viral particles are around 3 orders of magnitude smaller than the pores in surgical masks. So is there any evidence that surgical masks can filter aerosolized viral particles?
Re: Face masks effectively limit the probability of SARS-CoV-2 transmission
#3Not that this will settle anything.
Anecdotally, I've not gotten even a slight cold while being socially distanced while consistently masked.
Re: Face masks effectively limit the probability of SARS-CoV-2 transmission
#4>Surgical masks with particle collection efficiencies around ~50% cannot prevent the release of millions of particles per person and their inhalation by others (green dots in Fig. 1, B and D). In other words, the human-emitted respiratory particle number is so high that we cannot avoid inhaling particles generated by another person even when wearing a surgical mask So the entire premise of the modeling in the paper r…
Viral particles are concentrated in droplets and aerosols, which are significantly blocked by surgical masks.
Re: Face masks effectively limit the probability of SARS-CoV-2 transmission
#5>Surgical masks with particle collection efficiencies around ~50% cannot prevent the release of millions of particles per person and their inhalation by others (green dots in Fig. 1, B and D). In other words, the human-emitted respiratory particle number is so high that we cannot avoid inhaling particles generated by another person even when wearing a surgical mask So the entire premise of the modeling in the paper r…
Virus particles do not travel naked in the air, instead they are colloidally suspended in liquid, both droplets and aerosols.
So, if your filter catches the droplets and aerosols, which are much larger in size than the actual virus, the filter works.
Re: Face masks effectively limit the probability of SARS-CoV-2 transmission
#6Not that this will settle anything. Anecdotally, I've not gotten even a slight cold while being socially distanced while consistently masked.
Well, that may be due to other people social distancing enough to keep the level of colds down. It might have nothing to do with masks.
Re: Face masks effectively limit the probability of SARS-CoV-2 transmission
#7Not that this will settle anything. Anecdotally, I've not gotten even a slight cold while being socially distanced while consistently masked.
anecdotally, I have very little social contact normally anyway, I've worked from home since before winter, and always wear masks in closed public spaces - have had 3-4 colds in that time.
I do have kids though.
Re: Face masks effectively limit the probability of SARS-CoV-2 transmission
#8As suspected, it's exactly a probability game. If there's few infectious particles sure to low concentrations (e.g. people distance or are outdoors), you would roll the 70% penetration chance fewer times, and result in very few particles reaching deeper into lungs too as the velocities are reduced.
When very close to an active particle source, you'd roll the conditional probability dice many more times.
The critical number is the base infectivity or viability. (CFU essentially) It is expected that sub-viable numbers might even work as a kind of vaccination if people isolate long enough. (stay at home for prolonged time without contact - scale of days at least)
Re: Face masks effectively limit the probability of SARS-CoV-2 transmission
#9Not that this will settle anything. Anecdotally, I've not gotten even a slight cold while being socially distanced while consistently masked.
My 2yo would like to sneeze on you and flip that anecdote on its head.
Re: Face masks effectively limit the probability of SARS-CoV-2 transmission
#10Not that this will settle anything. Anecdotally, I've not gotten even a slight cold while being socially distanced while consistently masked.
It's more plausible, at least in my view, that this is the result of suppression of several endemic respiratory pathogens by viral interference (something that has been observed in previous pandemics).
https://medium.com/illumination-curated/the-unexpected-case-...