Thread by @jljcolorado

@Teddybird @krishlex @YouTube @gideonlasco @DOHgovph @ntfcovid19ph @iamguidodavid @friaronwater @trishgreenhalgh @DFisman @CDCgov @Harvard Transmission in close proximity is dominated by short-range airborne transmission (aerosol inhalation) -- NOT droplets.

And most spaces worldwide (even the US) are poorly ventilated, as we can easily verify measuring CO2 (#covidCO2). So a lot of shared-room transmission

@Teddybird @krishlex @YouTube @gideonlasco @DOHgovph @ntfcovid19ph @iamguidodavid @friaronwater @trishgreenhalgh @DFisman @CDCgov @Harvard For example the Norway restaurant superspreading event for omicron led to 75% of the current omicron cases in that country. So clearly shared room transmission is major.

And 10% of cases --> 80-90% of transmission. Mostly shared room airborne superspread: nature.com/articles/d4158…

@Teddybird @krishlex @YouTube @gideonlasco @DOHgovph @ntfcovid19ph @iamguidodavid @friaronwater @trishgreenhalgh @DFisman @CDCgov @Harvard Some people argue that contact tracing results indicate that most transmission is in close proximity. But that's a circular argument. Contact tracing only investigates close proximity.

Like drunk person who only looks for keys below the streetlight (en.wikipedia.org/wiki/Streetlig…)

@Teddybird @krishlex @YouTube @gideonlasco @DOHgovph @ntfcovid19ph @iamguidodavid @friaronwater @trishgreenhalgh @DFisman @CDCgov @Harvard Of course those are the factors:

- community incidence rates --> more infectious people exhaling aerosols
- viral load --> more exhaled aerosols
- symptoms --> coughing increases aerosol emission a lot
- proximity: less dilution, more of the exhaled aerosols are inhaled

@Teddybird @krishlex @YouTube @gideonlasco @DOHgovph @ntfcovid19ph @iamguidodavid @friaronwater @trishgreenhalgh @DFisman @CDCgov @Harvard - duration of exposure: more virus accumulates in the air, and more air with virus is inhaled
- poor ventilation: virus accumulates in the air, more chances to breathe

“Not dependent on airborne route"--> wrong, almost EVERY factor is BECAUSE of airborne route

@Teddybird @krishlex @YouTube @gideonlasco @DOHgovph @ntfcovid19ph @iamguidodavid @friaronwater @trishgreenhalgh @DFisman @CDCgov @Harvard In fact, those are EXACTLY the factors in our mathematical model that EXPLAINS the REAL superspreading events!!

(see this part of the thread explaining the paper)

https://twitter.com/jljcolorado/status/1479263100691959808