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Improving ventilation will help curb SARS-CoV-2

economist.com

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Re: Improving ventilation will help curb SARS-CoV-2

#141
post #74

Earlier quoted context omitted.

https://www.who.int/docs/default-source/coronaviruse/transcr... Coronavirus press conference 11 February, 2020 Tedros gives the money quote: > That was exactly what we were trying to do in DRC so we don't want, as WHO, to go into speculation. Okay, people can have projections. We prefer, what can be done with the equipment or the solutions at hand and do our best to contain it at the source without undermining its gr…

WHO was not pressured into saying not to ban flights from China. The International Health Regulations (2005),[1] which govern the WHO, and which the US played a key role in drafting, strongly discourage travel restrictions. The WHO is supposed to urge member countries to keep their borders open as much as possible, and to only institute travel restrictions if there is clear scientific evidence that they will help. Pr…

> If you look at how SARS-CoV-2 initially spread in the US, the WHO was not wrong. The US banned travel from China, but continued to allow travel from Europe. The first major outbreak in the US, in NY, was brought in from Europe.

It’s worth noting that there’s evidence it was already spreading in Seattle in Jan/Feb, following a Chinese import, before the late Feb/March outbreak in New York (which, yes, appears to have begun with European imports).

https://www.cdc.gov/mmwr/volumes/69/wr/mm6922e1.htm

Re: Improving ventilation will help curb SARS-CoV-2

#142
post #95

Earlier quoted context omitted.

> FACT: COVID-19 is NOT airborne. > The coronavirus is mainly transmitted through droplets generated when an infected person coughs, sneezes or speaks. > To protect yourself: > -keep 1m distance from others > -disinfect surfaces frequently > -wash/rub your > -avoid touching your From: https://www.facebook.com/WHO/posts/fact-covid-19-is-not-airb... Further reading: https://www.forbes.com/sites/jvchamary/2021/05/28/who…

Interesting to look at the replies to the Facebook post from over a year ago. It was patently clear to everyone back then that the WHO was wrong about this.

No, the WHO was right, and still is, epidemiologically speaking. The problem is that there is a difference in meaning between "this virus is airborne" and "this virus can spread through the air via aerosols".

The former means that the virus itself can survive being exposed to the air, which means it can float for hours and spread easily over large distances.

The latter means that the virus can only survive in the air when encapsulated in a liquid, which means it can not hover in the air for long (due to the weight of the droplet) and thus not spead over large distances.

Re: Improving ventilation will help curb SARS-CoV-2

#143
post #95

Earlier quoted context omitted.

> FACT: COVID-19 is NOT airborne. > The coronavirus is mainly transmitted through droplets generated when an infected person coughs, sneezes or speaks. > To protect yourself: > -keep 1m distance from others > -disinfect surfaces frequently > -wash/rub your > -avoid touching your From: https://www.facebook.com/WHO/posts/fact-covid-19-is-not-airb... Further reading: https://www.forbes.com/sites/jvchamary/2021/05/28/who…

Years later I still run into people not aware of the semantics and the difference between a disease being an aerosol and a disease being airborne. Which smacks of poor communication.

The root cause is that intelligent, educated people misunderestimate the reactionary idea among the masses that their ignorance is just as, or more, valid.

Revolutions are not won by people who are smart at facts but by people who are smart at manipulating ignorance.

Re: Improving ventilation will help curb SARS-CoV-2

#144
post #95

Earlier quoted context omitted.

> FACT: COVID-19 is NOT airborne. > The coronavirus is mainly transmitted through droplets generated when an infected person coughs, sneezes or speaks. > To protect yourself: > -keep 1m distance from others > -disinfect surfaces frequently > -wash/rub your > -avoid touching your From: https://www.facebook.com/WHO/posts/fact-covid-19-is-not-airb... Further reading: https://www.forbes.com/sites/jvchamary/2021/05/28/who…

> The coronavirus is mainly transmitted through droplets generated when an infected person coughs, sneezes or speaks. Emphasis mine. Honestly there was no way around the mess, thanks to social media amplifying any popular outrage and misunderstanding to 11. And I'm not excusing the WHO, their role has been borderline criminal at the beginning, and their reactions slow, but it's also very difficult to convey complex i…

They could have just pointed everyone to that video made by Japanese researchers that shows how long aerosols can remain airborne and circulate in a room as well as how they are dispersed from the mouth by coughing, sneezing and talking. It was very illustrative and was ready made and waiting for a situation like this.

Re: Improving ventilation will help curb SARS-CoV-2

#145
post #6

> The who therefore played down the risks of aerosols, issuing guidance via its Twitter and Facebook pages at the end of March 2020 that the general public need not worry. “FACT: #COVID19 is NOT airborne,” it said, adding that any claims to the contrary were “misinformation”. Not quite the money quote, but on reading this I wanted to point out one little thing. This is also a form of authoritarianism, not the splashy…

Well that March 2020 quote is still correct, isn't it? You as a layperson just think that airborne means something it doesn't mean for virologists (aerosol transmission airborne virus). So the tweet certainly was a typical science communication error, i.e. they forgot that words can have different meanings in different milieus, but it wasn't wrong.

https://www.who.int/news-room/commentaries/detail/modes-of-t... seems to use airborne to mean transmission in small droplets.

Airborne transmission is different from droplet transmission as it refers to the presence of microbes within droplet nuclei, which are generally considered to be particles

Re: Improving ventilation will help curb SARS-CoV-2

#146

Earlier quoted context omitted.

Well that March 2020 quote is still correct, isn't it? You as a layperson just think that airborne means something it doesn't mean for virologists (aerosol transmission airborne virus). So the tweet certainly was a typical science communication error, i.e. they forgot that words can have different meanings in different milieus, but it wasn't wrong.

https://www.who.int/news-room/commentaries/detail/modes-of-t... seems to use airborne to mean transmission in small droplets. Airborne transmission is different from droplet transmission as it refers to the presence of microbes within droplet nuclei, which are generally considered to be particles

The same article then also goes on to reason why this doesn't seem to be the dominant way of transmission outside special circumstances (like ventilation).

I don't have a background in this topic at all, but apparently actual airborne viruses are really small: Measles is about 200 nm and Influenza about 100 nm in diameter, while Sars-Cov-2 is about 1000 nm, so 5 to 10 times the diameter and thus 100 to 1000 times the mass.

Re: Improving ventilation will help curb SARS-CoV-2

#148

Earlier quoted context omitted.

https://www.who.int/news-room/commentaries/detail/modes-of-t... seems to use airborne to mean transmission in small droplets. Airborne transmission is different from droplet transmission as it refers to the presence of microbes within droplet nuclei, which are generally considered to be particles

The same article then also goes on to reason why this doesn't seem to be the dominant way of transmission outside special circumstances (like ventilation). I don't have a background in this topic at all, but apparently actual airborne viruses are really small: Measles is about 200 nm and Influenza about 100 nm in diameter, while Sars-Cov-2 is about 1000 nm, so 5 to 10 times the diameter and thus 100 to 1000 times the…

My point is that the WHO is literally, in recent releases, contradicting the usage you claim was primarily a communication error.

Their measles info page doesn't even talk about airborne.

https://www.who.int/news-room/fact-sheets/detail/measles

Re: Improving ventilation will help curb SARS-CoV-2

#149
post #135
post #61

My town's school system is all in on healthy buildings -- they got parent MD/PhDs to read the literature and invite outside experts to advise, then they set minimum air change per hour and minimum filtration criteria (something like, classrooms may reopen iff they have 5 air changes per hour with outdoor or MERV 13+ filtered air). They did a bunch of HVAC work to support this goal and have reopened okay. The town's o…

> the pandemic is their once in a generation opportunity to push change in indoor air quality in the recent years many offices, especially new and deeply remodeled got "green" certified, and decreased ventilation flow has been among the ways to achieve the energy saving for the certification. I don't hope they would turn the ventilation/AC back on to good levels - instead i think there would spring a cottage industry…

I've seen the opposite problem. My apartment which just completed construction at the end of 2020 is very insulated, but has very aggressive air exchange through the HVAC system to compensate. My poor humidifier can't keep up, so the indoor air humidity is at the mercy of whatever the dew point is outside. It was consistently below 10% throughout February. I wonder which situation is worse for your health.

Re: Improving ventilation will help curb SARS-CoV-2

#150

Earlier quoted context omitted.

> The coronavirus is mainly transmitted through droplets generated when an infected person coughs, sneezes or speaks. Emphasis mine. Honestly there was no way around the mess, thanks to social media amplifying any popular outrage and misunderstanding to 11. And I'm not excusing the WHO, their role has been borderline criminal at the beginning, and their reactions slow, but it's also very difficult to convey complex i…

They could have just pointed everyone to that video made by Japanese researchers that shows how long aerosols can remain airborne and circulate in a room as well as how they are dispersed from the mouth by coughing, sneezing and talking. It was very illustrative and was ready made and waiting for a situation like this.

Unless we're talking of different videos, that's from september/october.
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