Thread by @jmcrookston

In summer 2020, the WHO wrote an article to support droplet transmission of COVID-19.

What if I told you that it went horribly awry, and actually helped prove aerosol?

Good news!

Have I got a thread for you!

In summer 2020, the WHO committee that sets COVID-19 transmission guidelines wrote a piece.

It argued for droplet, and contained many misconceptions and logical errors that have been dealt with elsewhere. I won't get into those.

https://twitter.com/jljcolorado/status/1291825139315744768

What I *do* want to note is that the authors say that while using droplet precautions (medical masks) no hospital workers got sick.

Citing to footnotes 44 and 45.

You know the drill. Let's go.

Here are the two footnotes. One is to one of the authors' old papers. I'll look at that one later. We're going to focus on 45.

Got it.

I won't bore you. The article says that in a hospital called Hospital B, no health care workers caught SARS despite irregular use of masks, and not using N-95 masks.

The SARS outbreak had started in another hospital, called Hospital A. *THAT* hospital had significant spread.

But in Hospital B, it does seem that there were obvious challenges that should have resulted in spread, but no spread happened.

The real issue was that before a certain date, the workers were not all using N-95 masks.

Only after March 19 did they use them consistently.

BUT, here's the thing ...

... in addition to the fact that health care workers had less to do with patient care because in Hospital B the families of the patients could take care of them (and the families weren't studied) ...

HOSPITAL B HAD GREAT VENTILATION!

Le fin.