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Why aren’t we talking more about airborne transmission?

theatlantic.com

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

#231

Post by jennyyang »

lmilcin wrote: post #225
jennyyang wrote: post #222

Earlier quoted context omitted.

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 A…

Thank you, you're repeating things I've already stated in my first post. I suggest reading things more carefully.

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

#232

Post by droopyEyelids »

lmilcin wrote: post #225
jennyyang wrote: post #222

Earlier quoted context omitted.

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 A…

In your refusal to read the article, you're missing how sars-cov-2 is teaching us new science about how viruses may survive in aerosols, which behave differently from particles that travel in a ballistic motion.

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

#233

Post by woeirua »

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…

All of the media messaging around COVID has been a complete disaster from the moment it became apparent it was spreading in January in China. One of the main takeaways from this pandemic needs to be that doctors and experts need to learn how to say the words: "I don't know, but we are working hard to find out." Way too many people have made statements that later turned out to be false. The lack of any consistency and the complete flip-flopping on masks has completely undermined the public's willingness to trust the experts.

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

#234

Post by heimatau »

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…

> 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

So, due to the very small size of this virus, in microns. Most air filters on the market are still not good enough. HEPA isn't good enough, is it better than nothing? Yes but not much. A MERV 14 isn't good enough. I've seen some promising UV light tech but...AC units are pretty ill equipped for this virus.

I'm even curious if studies have been done in hospitals have the equipped AC filtering system to stop this virus. Air flow and filtration is a tradeoff currently. Try to blow out a candle with an N95 mask. It's extremely difficult. The filter technology is not the same.

> orders of magnitude more effective than cloth masks

Cloth masks help about 40% reduction, surgical masks 80%, and N95...95%. I find it very annoying that governments are encouraging cloth masks because they could be use their size and buy surgical masks for everyone at a very cheap cost (economies of scale).

Also, the creator of N95 masks got out of retirement and found that if hospital workers had 7 masks, one for each day. Just rotating them in the storage closet is very effective to reusing them without contamination.

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

#235

Post by lmilcin »

droopyEyelids wrote: post #232
lmilcin wrote: post #225

Earlier quoted context omitted.

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 A…

In your refusal to read the article, you're missing how sars-cov-2 is teaching us new science about how viruses may survive in aerosols, which behave differently from particles that travel in a ballistic motion.

Airborne viruses have been known for a long, long time. The physics is established. The whole reason we distinguish between airborne and non-airborne viruses is exactly because virus needs special arrangements to be able to survive outside of fluid.

While it is interesting how particles move in a room, it is completely different topic. The particles ARE NOT AEROSOL. The kind of aerosol that can flow in tiny air currents dries out in seconds and becomes small particles (not droplets) of "relatively dry" matter that is fine enough to stay in air for a very long time.

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

#236

Post by heimatau »

mensetmanusman wrote: post #151
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…

Added benefit: post-covid pandemic, improved indoor air quality with all the included benefits! Air quality associated with: Alzheimers: https://www.scientificamerican.com/article/the-new-alzheimer... Cancers, plural: https://www.aacr.org/patients-caregivers/progress-against-ca... Sperm Quality: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4443398/#sec995... Female Fertility: https://www.newscientist.com/article/2207…

Thanks for these links. I've saved them for future reference!

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

#237

Post by DanBC »

lmilcin wrote: post #225
jennyyang wrote: post #222

Earlier quoted context omitted.

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 A…

These threads are awful because "droplet" and "aerosol" don't have good fixed definitions, and because people misuse the word "airborne" to mean "aerosol".

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

#238

Post by lmilcin »

DanBC wrote: post #237
lmilcin wrote: post #225

Earlier quoted context omitted.

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 A…

These threads are awful because "droplet" and "aerosol" don't have good fixed definitions, and because people misuse the word "airborne" to mean "aerosol".

Yes, there is a lot of education problem when you want to discuss anything virus related.

Aerosol == small droplets of water.

Airborne, particles == no droplet, just leftover of an aerosol that dried out in less than 100% humid air.

It would not be the first time that health-related article on an economic website gets physics wrong.

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

#239

Post by clairity »

coryrc wrote: post #198
clairity wrote: post #175

Earlier quoted context omitted.

> "...SARS-CoV-2 is airborne stable in aerosol form for over 3 hours..." see, this is the kind of insinuation that does none of us any good. it's like doing PCR to connote live virus particles live for 17 days on surfaces (spoiler: they don't). with that said, i'm down for air purifiers in living spaces† for a whole host of good health reasons, but most commercial spaces and public buildings (like schools) already ha…

If you are in the USA, I don't believe your claim that most commercial or schools have HEPA in their air filtration system, and know it isn't true for new residential in the PNW. The school I attended as a child didn't have any filtration at all, for example.

there's certainly variation, regional, by quality level, as well as generational. class A commercial will almost certainly have filtered hvac, for example. my 1930's vintage high school most certainly didn't.

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

#240

Post by fpgaminer »

clairity wrote: post #175
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…

> "...SARS-CoV-2 is airborne stable in aerosol form for over 3 hours..." see, this is the kind of insinuation that does none of us any good. it's like doing PCR to connote live virus particles live for 17 days on surfaces (spoiler: they don't). with that said, i'm down for air purifiers in living spaces† for a whole host of good health reasons, but most commercial spaces and public buildings (like schools) already ha…

> most commercial spaces and public buildings (like schools) already have HVAC systems incorporating HEPA filters (as good or better than N95 masks).

So, here's some anecdata. I have a PM2.5 sensor; not a great one, but good enough to measure relative changes. After buying an air purifier the PM2.5 count in our house dropped dramatically and consistently. Whereas the lower end before was a "2", now it reaches to "0"; I'd never seen the sensor register 0 before this. And the spikes from cooking are quickly scrubbed, whereas before they would cause a lingering increase in PM2.5 for the rest of the night.

Even though I spend extra to get the higher grade filters for our HVAC, an air purifier still seems to have objectively improved the air quality far beyond what our HVAC was doing.

In other words, I'm not sure an HVAC is a good replacement.

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