The Coronavirus Thread

[Brian Peacock]

Coronavirus: Airborne transmission cannot be ruled out, WHO says

The World Health Organization has acknowledged there is emerging evidence that the coronavirus can be spread by tiny particles suspended in the air.

The airborne transmission could not be ruled out in crowded, closed or poorly ventilated settings, an official said.

If the evidence is confirmed, it may affect guidelines for indoor spaces.

An open letter from more than 200 scientists had accused the WHO of underestimating the possibility of airborne transmission.

The WHO has so far said that the virus is transmitted through droplets when people cough or sneeze.

"We wanted them to acknowledge the evidence," Jose Jimenez, a chemist at the University of Colorado who signed the paper, told the Reuters news agency.

"This is definitely not an attack on the WHO. It's a scientific debate, but we felt we needed to go public because they were refusing to hear the evidence after many conversations with them," he said...

https://www.bbc.co.uk/news/world-53329946

[Scot Dutchy]

The Dutch RIVM and the WHO apparently disagrees but there you go. The battle of the aerosols. That post btw is in the wrong thread as it is an opinion trying to create bias.

[Brian Peacock]

It's part of the ongoing scientific debate about the nature of the virus and it's transmission. Scientific opinion is qualified by scientific rigour. Political opinions are qualified politically and ultimately boil moral arguments for/against action. The tension between the two arises when public health policies informed by medical science and political concerns are placed at odds with each other.

[rainbow]

The Dutch RIVM and the WHO apparently disagrees but there you go. The battle of the aerosols. That post btw is in the wrong thread as it is an opinion trying to create bias.

There is an arbitrary point at which one may call a bit of spit a droplet, or an aerosol.

What comes out of the gob has a Gaussian distribution of particle sizes.
https://www.tsi.com/getmedia/1621329b-f ... e?ext=.pdf

It will even vary from person to person, whether one is talking, just breathing, singing, shouting, sneezing or coughing.

...so there is neither a right or wrong answer on this.

What there is strong evidence for is that the chances of a droplet getting from an infected person to another decreases dramatically over the 1m to 2m distance.

How does one explain this to the average Dutch cyclist, or Evangelical Anabaptist?

[pErvinalia]

How to explain anything to our Dutch member?

[rainbow]

Another fascinating aspect of the particle size distribution is that the number of particles in the aerosol size range is quite high, but the total volume is very small (a few percent). That means that aerosolised viral loads will be lower by one to two orders of magnitude, compared to the droplets.
Also smaller particles dry out very much faster than bigger ones, thus making the virons unviable for transmission.
Therefore the risk is not zero from aerosols, just very much less.

[NineBerry]

The Dutch RIVM and the WHO apparently disagrees but there you go. The battle of the aerosols. That post btw is in the wrong thread as it is an opinion trying to create bias.

There is an arbitrary point at which one may call a bit of spit a droplet, or an aerosol.

What comes out of the gob has a Gaussian distribution of particle sizes.
https://www.tsi.com/getmedia/1621329b-f ... e?ext=.pdf

It will even vary from person to person, whether one is talking, just breathing, singing, shouting, sneezing or coughing.

...so there is neither a right or wrong answer on this.

What there is strong evidence for is that the chances of a droplet getting from an infected person to another decreases dramatically over the 1m to 2m distance.

How does one explain this to the average Dutch cyclist, or Evangelical Anabaptist?

The point about aerosols is that in an enclosed room, the small droplets can spread much further than 2m and build up over time. The experts over here now say this explains the problem with meat factories (Workers staying the in the same room for hours, heavy breathing, air venting that cools the air and doesn't exchange it but reuses it constantly) and churches (Congregants staying in the same room for hours, singing, no air venting)

[rainbow]

Transmissieroute COVID-19

Aerosolen bestaan uit een wolk van grote (> 5-10 µm) en kleine fijne druppels (< 5 µm) en druppelkernen. De kleine druppels en druppelkernen kunnen een grotere afstand afleggen en met name druppelkernen blijven langer in de lucht hangen (WHO). De huidige richtlijnen voor preventie van SARS-CoV-2 verspreiding zijn gebaseerd op de aanname dat mens-op-menstransmissie van SARS-CoV-2 voornamelijk direct plaatsvindt binnen een afstand van 1,5 m via druppelinfectie (via druppels met een diameter > 5-10 µm) die vrijkomen bij hoesten en niezen, of indirect via contact met besmette voorwerpen of oppervlakken (WHO, CDC). Daarnaast kunnen ook grote hoeveelheden kleine druppels (< 5 µm) die vrijkomen tijdens aerosolvormende medische handelingen, bijvoorbeeld bij tracheale intubatie, tot (directe en indirecte) transmissie leiden (WHO, 2020; LCI, FMS). In hoeverre druppelkernen die geen vocht bevatten levensvatbaar virus kunnen bevatten, is niet bekend i.t.t. tuberculose waarbij dit wel is aangetoond.

https://lci.rivm.nl/aerogene-verspreidi ... derbouwing

Wot I sed.

[NineBerry]

De kleine druppels-

This sounds so sweet. I want to have some of them and cuddle with them.

[rainbow]

The point about aerosols is that in an enclosed room, the small droplets can spread much further than 2m and build up over time. The experts over here now say this explains the problem with meat factories (Workers staying the in the same room for hours, heavy breathing, air venting that cools the air and doesn't exchange it but reuses it constantly) and churches (Congregants staying in the same room for hours, singing, no air venting)

Yes, so if the air is recirculated, cooled and humid, the smaller particles will still transmit. In the case of meat packing factories, I'd agree with you.

If you really have to go to church, wear an aqualung, and don't sing.

[NineBerry]

Transmissieroute COVID-19

Aerosolen bestaan uit een wolk van grote (> 5-10 µm) en kleine fijne druppels (< 5 µm) en druppelkernen. De kleine druppels en druppelkernen kunnen een grotere afstand afleggen en met name druppelkernen blijven langer in de lucht hangen (WHO). De huidige richtlijnen voor preventie van SARS-CoV-2 verspreiding zijn gebaseerd op de aanname dat mens-op-menstransmissie van SARS-CoV-2 voornamelijk direct plaatsvindt binnen een afstand van 1,5 m via druppelinfectie (via druppels met een diameter > 5-10 µm) die vrijkomen bij hoesten en niezen, of indirect via contact met besmette voorwerpen of oppervlakken (WHO, CDC). Daarnaast kunnen ook grote hoeveelheden kleine druppels (< 5 µm) die vrijkomen tijdens aerosolvormende medische handelingen, bijvoorbeeld bij tracheale intubatie, tot (directe en indirecte) transmissie leiden (WHO, 2020; LCI, FMS). In hoeverre druppelkernen die geen vocht bevatten levensvatbaar virus kunnen bevatten, is niet bekend i.t.t. tuberculose waarbij dit wel is aangetoond.

https://lci.rivm.nl/aerogene-verspreidi ... derbouwing

Wot I sed.

It's outdated information. There are examples of mass-infections at settings like choir practices and church services where distances were kept and the virus could still spread massively.

[rainbow]

[NineBerry]

[rainbow]

If you really have to go to church, wear an aqualung, and don't sing.

[Svartalf]