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Your claims do not reflect what the article and the evidence it cites show. To quote:

> Cowling told me that it’s better to call these “short-range aerosols,” as that communicates the nature of the threat more accurately: Most of these particles are concentrated around the infected person, but, under the right circumstances, they can accumulate and get around.

This is the precise opposite of your claim that 6 foot distancing would "matter little under aerosol conditions where air flow patterns dominate transmission." AT NO POINT does the article indicate that droplets are irrelevant. We know they are the key factor in person-to-person transmission. But we also now have evidence that short-range aerosols also play a role, especially in superspreading events.

The evidence is VERY clear that risks are highest in close proximity to infected individuals.

I would encourage you to take another look at the article and read closely.



Well first of all there is little evidence on both sides of the argument here. There isn't much evidence in favor of aerosol transmission and there isn't much evidence against it either. I would hope that more research can be done on this matter.

Perhaps I worded my statement poorly. Let me try to be more precise about the idea I was trying to express. If COVID really is more aerosol infectious than we have been assuming then the 6 foot distancing would matter much less in comparison because if a cloud of infectious COVID droplets is whirling in the air currents that effect will tend to dominate in the sense that your exact location relative to the COVID+ source is no longer a direct causal factor. Yes of course being farther away makes it less likely that you will be in the path of a relatively short range aerosol cloud but the important thing in that circumstance is not to be in its path and just being farther away in the same room may not be enough to avoid it.

I don't deny that if someone with COVID coughs directly in your face which apparently was considered the dominant transmission vector at first you are also likely to be infected especially if you are not fully and properly masked and goggled. That must happen sometimes. Of course being at least 6 feet away from the closest person is a good thing. It is just the assumption that that is enough to keep people safe from COVID that should be questioned more.

Anyway my quibble with your post was the part about the guidelines being the same. They aren't really. The difference may be slight, but it could be critical.


If you're claiming there's "isn't much evidence" indicating aerosol transmission, I would once again encourage you to read the article closely. There are several well-documented case clusters cited in the article where infections could really ONLY be explained by some degree of aerosol transmission. But aerosols vs. droplets aren't a black-and-white situation: people expel a whole range of different particle sizes, and where we draw the line between droplets and aerosols is largely arbitrary (small droplets just above that line behave much the same as big aerosols just below it).

Small "droplets" can travel some distance too. 6 feet isn't a magical boundary beyond which droplets completely vanish. Nor do particles just below the aerosol vs droplet threshold magically become non-infectious. There's a continuum of behavior. Public health authorities KNOW all this, and have known it from the beginning. But they also know that the public needs simple, clear guidance to take action. So, they have to simplify their explanations and inevitably some detail will be lost.

What we know now is that smaller particles (short-distance aerosols) play a bigger role than initial data suggested. But the evidence still suggests SARS-CoV-2 usually requires pretty close contact or circumstances that concentrate aerosols: limited ventilation on cruise ships, for example, or people singing for an extended period (producing a much higher volume of aerosols).

> I don't deny that if someone with COVID coughs directly in your face which apparently was considered the dominant transmission vector at first

This is not even REMOTELY what "droplet transmission" means. If that was what it took, NOBODY would be getting sick. Droplet transmission can come from talking, or being near someone yelling a drink order in a bar, sharing a cab, attending a dinner party, etc. It just implies fairly close contact.

> Anyway my quibble with your post was the part about the guidelines being the same. They aren't really. The difference may be slight, but it could be critical.

Every single piece of public health advice is imperfect, because they have to simplify complex situations. None of the original safety measures were actually WRONG -- all help protect against short-distance aerosols. The new evidence just adds another layer to the situation, and places extra emphasis on certain measures.

If the public and politicians had actually followed the original public health guidance, the situation would look much better than it does today.




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