Thread by @jljcolorado

1/ The error conflating short-range airborne transmission (aerosol inhalation) with large droplet (sprayborne) transmission is alive an well in this Facebook post from a Philippines Government advisor:

[Can't reply there, so I will here]

2/ He is strangely defining airborne as ONLY long range. That makes no sense.

The protection measures depend on the mechanism, NOT ON THE DISTANCE.

3 key mechanisms per @CDCgov
(1) Aerosol inhalation
(2) Large droplet spray
(3) Surface touch

cdc.gov/coronavirus/20…

3/ It is clear that aerosol inhalation, i.e. airborne transmission (at ALL DISTANCES) is the dominant mode of transmission. There is overwhelming evidence of this, e.g.:

https://twitter.com/jljcolorado/status/1383566908797059078

4/ Here we have some Harvard infection prevention doctors telling us the same thing, but with a focus on transmission in hospitals

Note that the REAL "aerosol generating procedures" are talking, singing, exercise... and for the most part NOT the AGMPs

dx.doi.org/10.7326/M21-27…

5/ Aerosol inhalation can happen at 3 distances:

(a) close proximity, important (low dilution of exhaled virus-containing aerosols)
(b) shared-room air, more dilution but more time + people (ALL superspreading, as we have shown recently, see thread)

https://twitter.com/jljcolorado/status/1479250147330637825

6/ (c) Longer-range, when people not sharing room air at the same time. This also happens, there are many documented cases (see see case in quarantine hotel linked). But thought to be a smaller fraction of transmission, because of high dilution.

https://twitter.com/jljcolorado/status/1479253250549370883

7/ To protect from inhalation need GOOD FITTING & FILTERING MASKS (e.g. N95) at ALL DISTANCES

Makes no sense to say that if transmission happens close to the person, i'ts droplet transmission & surgical masks ok

How can we have superspread w/o high aerosols in close proximity?

8/ I was talking to a Filipino colleague who lamented "the Philippines is really unfortunate to have these people providing erroneous public health messages"

Unfortunately they are not alone by a long shot!

That's why we have #COVIDHallofShame (> 120)

https://twitter.com/jljcolorado/status/1471160707794276353

9/ In fact I'd say that the Filipino situation is better than others. Those experts present erroneous information very clearly. So one can point out errors & debate

But others (#BonnieHenry comes to mind, but many more) present unintelligible word salads & alternative facts