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Why aren’t we talking more about airborne transmission?

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Re: Why aren’t we talking more about airborne transmission?

#221

Post by ceejayoz »

R0b0t1 wrote: post #189
frenchy wrote: post #156

Earlier quoted context omitted.

So I read those, and at least according to the WHO document, it seems to be the case that while viral RNA is detectable in a non-aersolized state in the air, they haven't been able to find any cases of this causing infection (See section labelled "Airborne transmission").

The thing is -- why assume it can't form aerosols and that those aerosols aren't infectious? By demanding evidence for aerosol formation that is what they are stating. It makes no sense. Most viruses do form aerosols, and those aerosols do seem to be infectious. Are you really prepared to make the bet that they aren't infectious?

> Most viruses do form aerosols, and those aerosols do seem to be infectious.

It's my understanding that most don't spread in this fashion. If you're hospitalized with cold/flu, your care team will observe droplet precautions, not aerosol ones.

If you have measles, which spreads via aerosol, they'll be using substantially more gear. The aerosol transmission is also why measles is shockingly easy to spread versus most other diseases.

Re: Why aren’t we talking more about airborne transmission?

#222

Post by jennyyang »

lmilcin wrote: post #208
prutschman wrote: post #157

Earlier quoted context omitted.

I don't see what was incorrect about the parent. It goes on to say "However, there are microdroplets which stay in the air for 30+ minutes depending on the air currents." It sounds like you're both in agreement that large droplets fall quickly to the ground, and that with COIVD the longer-lasting micro-droplets are a relevant factor. Am I missing a subtlety?

There are no "microdroplets" which stay in the air for "30+" minutes. First, water DRIES OUT unless the humidity is very close to 100% which is relatively rare in western countries. The smaller droplet the faster this happens. Put a very, very small droplet on a flat surface like glass. Observe it disappear within couple of minutes. Then imagine that a smaller droplet is just larger droplet closer to drying out. Volu…

I suggest you educate yourself on the topic of microdroplets.

https://www.weforum.org/agenda/2020/04/coronavirus-microdrop...

Re: Why aren’t we talking more about airborne transmission?

#223

Post by fragmede »

raziel2p wrote: post #75
jennyyang wrote: post #32

After this pandemic, doctors and scientists are going to have to come up with more media-friendly terms from now on. The problem is that "airborne droplets" and "airborne" sound too similar and it's very hard for regular people to understand what that means. "Airborne droplets" means that viruses need saliva to transmit between people. "Airborne" means that the virus only needs dust particles to transmit to other peo…

I don't agree with your conclusion. Airborne is airborne regardless of whether it's 5 minutes or 12 hours. The point of the word is to tell people that you can become infected without being in direct physical contact with them. Trying to come up with words for different durations of airborne is only going to make it more confusing, even if it becomes less ambiguous to the people who know the difference between the te…

It's possible, if annoying, to simply wait 5 minutes between trips while the elevator car's air clears. It has to be handled differently (eg using a fan) if it would take 12 hours for the air to clear.

Given that we are all talking about COVID-19, as caused by the SARS-Cov-2 virus, (and not any other disease), the exact word or phrase used in popular media is less important, what's important is for people to recognize that breathing someone's are 5 minutes later is hazardous. Would you even know if there was person in the same elevator car as you 5 minutes before you came along? How can you recognize if they were actively symptomatic and positive and not wearing a mask. What it's called by scientists is less important compared to outright science denial going on.

Even before "global warming" was renamed "global climate change", people are able to learn and understand the phenomena that it refers to, even if there are idiots that say "global warming isn't real" because they felt cold at some point. With today's instant access to information, I want to push back against the idea that everybody who cares to ask is too dumb to learn the difference between "airborne" (12 hours) vs "airborne droplets" (5 minutes).

Re: Why aren’t we talking more about airborne transmission?

#224

Post by Vysero »

mensetmanusman wrote: post #125

I am still shocked: months after research has shown that SARS-CoV-2 is airborne stable in aerosol form for over 3 hours, we still aren’t telling the public that room air purifiers are a ‘good thing’ (for making indoor air like outdoor air - in regards to virion density per cubic air volume) The filter technology is essentially the same as in the N95, orders of magnitude more effective than cloth masks. Put these indo…

If they can't put these everywhere they should at least target the minority's in our country who are most susceptible; specifically, people over the age of 75.

Re: Why aren’t we talking more about airborne transmission?

#225

Post by lmilcin »

jennyyang wrote: post #222
lmilcin wrote: post #208

Earlier quoted context omitted.

There are no "microdroplets" which stay in the air for "30+" minutes. First, water DRIES OUT unless the humidity is very close to 100% which is relatively rare in western countries. The smaller droplet the faster this happens. Put a very, very small droplet on a flat surface like glass. Observe it disappear within couple of minutes. Then imagine that a smaller droplet is just larger droplet closer to drying out. Volu…

I suggest you educate yourself on the topic of microdroplets. https://www.weforum.org/agenda/2020/04/coronavirus-microdrop...

I suggest you educate yourself.

https://en.wikipedia.org/wiki/Airborne_disease

"Airborne transmission is distinct from transmission by respiratory droplets. Respiratory droplets are large enough to fall to the ground rapidly after being produced (usually greater than 5 μm), as opposed to the smaller particles that carry airborne pathogens. Also, while respiratory droplets consist mostly of water, AIRBORNE PARTICLES ARE RELATIVELY DRY, which damages many pathogens so that their ability to transmit infection is lessened or eliminated."

Here, I capitalized it for you so you don't miss it.

Airborne virus is what happens after fine respiratory mist dries out, which happens quite quickly. It is "relatively" dry because some of the respiratory fluid is hygroscopic. Don't make a mistake, there is no free flowing liquid with virus happily swimming in it.

Re: Why aren’t we talking more about airborne transmission?

#226

Post by Vysero »

MiguelVieira wrote: post #56

When I look at this heat map of recent cases per capita in the US https://globalepidemics.org/key-metrics-for-covid-suppressio... the first thing I see is hot spots all across the southeast and desert southwest. These places have widely varying governments and cultures, but the one thing they do have in common right now is: they're hot. My suspicion is that many of the outbreaks we've seen recently are caused by peop…

Ben Shapiro has been saying that for months..

Re: Why aren’t we talking more about airborne transmission?

#227

Post by hcurtiss »

jennyyang wrote: post #120
jtbayly wrote: post #68

Earlier quoted context omitted.

> we would have to implement extremely strict lockdowns... if we assume that the goal is not to flatten the curve but to completely stop the virus in its tracks. Most people and countries don't have this goal. Edit: To those downvoting, I'll just say that my statement is factual, so argue the facts. Long-term, we want a vaccine, yes. In the meantime, most people and countries are simply not willing to do what it take…

If the virus were truly airborne, which it isn't, then simply walking through an empty room could get you infected. The levels of people getting infected, and subsequently getting hospitalized would be far worse than the worst scenes we saw in Italy and NYC. Lockdowns absolutely would have been mandatory for months upon months. Coronavirus is not by itself a tremendously deadly disease. The problem is how infectious…

>Even stores like Costco and all factories would have to shut down.

That would kill a lot of people too. It's not obvious to me which would be worse, particularly in the face of such a low IFR.

Re: Why aren’t we talking more about airborne transmission?

#228

Post by timr »

SkyPuncher wrote: post #118
jennyyang wrote: post #32

After this pandemic, doctors and scientists are going to have to come up with more media-friendly terms from now on. The problem is that "airborne droplets" and "airborne" sound too similar and it's very hard for regular people to understand what that means. "Airborne droplets" means that viruses need saliva to transmit between people. "Airborne" means that the virus only needs dust particles to transmit to other peo…

> If someone with coronavirus sneezes in a room, the large heavy droplets will quickly fall to the ground. This is the slightly incorrect part with COVID. Traditionally, this would be an appropriate description for other droplet transmission (like the flu). However, it seems COVID has an above average ability to survive in extremely fine droplets - think mist-sized particles that CAN float in the air for an extended…

"However, it seems COVID has an above average ability to survive in extremely fine droplets - think mist-sized particles that CAN float in the air for an extended period of time (given the right circumstances)."

This is one of those "facts" that is often repeated, but which has little actual evidence if you bother to look for it. The WHO has been consistent that aerosol transmission of the virus is a theory with little backing evidence:

Some outbreak reports related to indoor crowded spaces have suggested the possibility of aerosol transmission, combined with droplet transmission, for example, during choir practice, in restaurants, or in fitness classes. In these events, short-range aerosol transmission, particularly in specific indoor locations, such as crowded and inadequately ventilated spaces over a prolonged period of time with infected persons cannot be ruled out. However, the detailed investigations of these clusters suggest that droplet and [transmission from contaminated surfaces or objects] could also explain human-to-human transmission within these clusters."

"Current evidence suggests that SARS-CoV-2 is primarily transmitted between people via respiratory droplets and contact routes – although aerosolization in medical settings where aerosol generating procedures are used is also another possible mode of transmission"

https://www.who.int/news-room/commentaries/detail/transmissi...

ARS did a pretty good job of summarizing the (IMO terrible) mass-media reporting on this issue:

https://arstechnica.com/science/2020/07/no-the-who-has-not-r...

Re: Why aren’t we talking more about airborne transmission?

#229

Post by echelon »

jennyyang wrote: post #32

After this pandemic, doctors and scientists are going to have to come up with more media-friendly terms from now on. The problem is that "airborne droplets" and "airborne" sound too similar and it's very hard for regular people to understand what that means. "Airborne droplets" means that viruses need saliva to transmit between people. "Airborne" means that the virus only needs dust particles to transmit to other peo…

More important would be fixing the messaging on masks and protection. (Most laymen aren't going to distinguish between droplet, aerosol, airborne, etc. and won't adjust behavior and risk profiles accordingly.)

The CDC told people that masks were not important at the start of the pandemic, largely as a means of reserving stock for doctors and first responders. They then performed an uneven and awkwardly stilted 180 on that message. This massively backfired and led to wide scale public distrust of the public health apparatus. The birth of the anti-mask movement, etc.

We'll be living with the ramifications for a long time.

You shouldn't lie to the public.

Re: Why aren’t we talking more about airborne transmission?

#230

Post by ChuckMcM »

jennyyang wrote: post #32

After this pandemic, doctors and scientists are going to have to come up with more media-friendly terms from now on. The problem is that "airborne droplets" and "airborne" sound too similar and it's very hard for regular people to understand what that means. "Airborne droplets" means that viruses need saliva to transmit between people. "Airborne" means that the virus only needs dust particles to transmit to other peo…

And we have studies[1] that show UV light kills the virus in less than a minute which further limits airborne spread outdoors during the day[2].

[1] https://www.cuimc.columbia.edu/news/far-uvc-light-safely-kil...

[2] Even on overcast days, as people who forgot sunscreen on cloudy days can attest too.

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