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AFAICT that's a semantic debate around the size and range of particles without universally agreed of definitions of the terms. Trying to categorize transmission

by yosito 6y ago

AFAICT that's a semantic debate around the size and range of particles without universally agreed of definitions of the terms. Trying to categorize transmission into binary modes seems a little futile. Of course, studying and modelling the exact dynamics of particle transmission is useful, but the headline and linked study seemed to be related to a binary question of whether or not airborne transmission happens, which is a question that's been thoroughly answered for several months.

wk_end 6y ago
It’s not a mere semantic debate - if I understand correctly (not a virologist or anything) the implications are huge. Droplets are ejected from the face and basically fall straight to the ground. This is what makes things like six feet “socially distancing” rules effective - you basically need to be in a direct, face-to-face interaction with someone to spread the virus. Airborne transmission in the technical sense means that the virus can float along in the air, potentially for hours in a poorly ventilated space: most social distancing NPIs become nearly meaningless. Staying outside or improving indoor ventilation become the big things that matter. Also, droplets are large and are stopped effectively even by the sort of cheap, relatively loose-fitting masks people are wearing. If airborne transmission is a major problem, that’s no longer really the case; we all need N95s to make much of an impact.
- yosito 6y ago
  You're not wrong. But the point I'm making is that "droplet" vs "aerosol" is not binary. There is a wide range of particle sizes. There are particles that immediately fall to the ground, and there are particles that float around in the air for days, and there is everything in between. It's been shown for over a year that COVID can be transmitted in particles that float in the air for some time. Exactly how much time and in what conditions should be studied, but we're long past the question of whether it happens or not.
  - klmadfejno 6y ago
    That's an obvious insight I hadn't considered before.

by yosito 6y ago

wk_end 6y ago

It’s not a mere semantic debate - if I understand correctly (not a virologist or anything) the implications are huge. Droplets are ejected from the face and basically fall straight to the ground. This is what makes things like six feet “socially distancing” rules effective - you basically need to be in a direct, face-to-face interaction with someone to spread the virus. Airborne transmission in the technical sense means that the virus can float along in the air, potentially for hours in a poorly ventilated space: most social distancing NPIs become nearly meaningless. Staying outside or improving indoor ventilation become the big things that matter. Also, droplets are large and are stopped effectively even by the sort of cheap, relatively loose-fitting masks people are wearing. If airborne transmission is a major problem, that’s no longer really the case; we all need N95s to make much of an impact.

yosito 6y ago
You're not wrong. But the point I'm making is that "droplet" vs "aerosol" is not binary. There is a wide range of particle sizes. There are particles that immediately fall to the ground, and there are particles that float around in the air for days, and there is everything in between. It's been shown for over a year that COVID can be transmitted in particles that float in the air for some time. Exactly how much time and in what conditions should be studied, but we're long past the question of whether it happens or not.
- klmadfejno 6y ago
  That's an obvious insight I hadn't considered before.