10 ms·

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" an

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 people. Measles is airborne transmission, which means that if someone with measles enters a room, that room can be infectious for 12+ hours because viruses will be infectious in the dust. If someone with coronavirus sneezes in a room, the large heavy droplets will quickly fall to the ground. If you breathe in the droplets then you can catch the virus, but these only stay in the air for seconds. However, there are microdroplets which stay in the air for 30+ minutes depending on the air currents. So there is a distinction between them. If coronavirus were truly airborne, then we would all need to wear masks all the time, even when no one is around. No where would be safe and we would have to implement extremely strict lockdowns. But the fact that scientists and doctors have chosen to use the term "airborne" in both have made it extremely confusing and given how quickly information and misinformation is disseminated these days, they need to choose terms with care from now on.

enraged_camel 6y ago
The article addresses this midway through. The problem is that even the experts haven't really agreed on terminology. They need to do that first before they can hope to inform the public. :)
- mc32 6y ago
  So why talk about HVAC systems ? Context: >” by 10 bottles of hand sanitizer without a word on ventilation—whether it was opening windows, employing upgraded filters in its HVAC systems, or using portable HEPA filters. It seems baffling that despite mounting evidence of its importance, we are stuck practicing hygiene theater...”
  - enraged_camel 6y ago
    Sorry, what do you mean?
    - vladTheInhaler 6y ago
      I suspect the parent post meant "why not", as in "improving HVAC would be more effective than the omnipresent hand sanitizer, so why aren't we talking about that?"
mc32 6y ago
One important point that comes out of this is that few people are stressing shoe sole hygiene. Not necessarily meaning that one has to scrub them often, but to be mindful of what it touches (car interior mats, mats at home and possibly if people don’t take off their shoes, all over the house, hands taking off shoes, shoe racks, etc.) Given that droplets mean the virus will accumulate on floors and such surfaces.
- dpeck 6y ago
  A place to put outside shoes and put on inside slippers (flip flops in my case) is good for clean floors anyway. I highly recommend, whether that’s a little mudroom or just a walled rubber/plastic container to take off shoes. That said, I’m not sure it does much for this particular virus, but it can’t hurt and your floors (especially carpets, but those are nasty anyway) stay much cleaner.
- dalyons 6y ago
  why would that matter? transmission from surfaces is apparently quite low, and it doesnt last long on surfaces, and its not like im touching / eating off anything my shoes come into contact with anyway. This feels like an incredibly low risk vector
  - mc32 6y ago
    Low but greater than the “aerosolized” vector. When people sneeze, it land on surfaces (like floors), when they cough, etc. If surfaces were not a problem, we wouldn’t be using wipes and sanitizers. So why ignore one possibility and stress another? When people take off their shoes they can get contaminated. If they have pets the pets will pick some up and get it on you, etc.
    - wk_end 6y ago
      The incessant use of wipes and sanitizers is basically "Hygiene Theatre" [1]. > In May, the Centers for Disease Control and Prevention updated its guidelines to clarify that while COVID-19 spreads easily among speakers and sneezers in close encounters, touching a surface “isn’t thought to be the main way the virus spreads.” Other scientists have reached a more forceful conclusion. “Surface transmission of COVID-19 is not justified at all by the science,” Emanuel Goldman, a microbiology professor at Rutgers New Jersey Medical School, told me. [1] https://www.theatlantic.com/ideas/archive/2020/07/scourge-hygiene-theater/614599/ https://www.theatlantic.com/ideas/archive/2020/07/scourge-hy...
jtbayly 6y ago
> 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 takes to completely eliminate this virus. They think it would be nice if the virus went away, but they are not working towards that as their goal.
- jennyyang 6y ago
  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 it is, and how quickly it can overrun a limited hospital system. Even at a sub-10% hospitalization rate for people younger than 60, we are seeing many hospitals getting full. It being truly airborne would make things worse by many orders of magnitude. The way coronavirus spreads is basically the same mechanism as the flu and the cold, yet the levels of people getting infected are much much worse. Imagine if simply walking through a room could get you infected. The spread would be undeniably worse than anything we had every seen before. Even stores like Costco and all factories would have to shut down. So yes, very strict lockdowns would need to be in place. Thank goodness it's not.
  - mensetmanusman 6y ago
    Um.. it is airborne, that is why there are multiple super-spreader events that can’t be explained by someone interacting within 3-6 feet for 10 minutes. (e.g. cases of 1 to 100, 1:500 case reported as well). If you walked into an empty hospital room that was just used with high air-virion density, you could get infected, that is why they decontaminate with the equipment you see. I think the main reason this isn’t being communicated is because we will never have enough N95 masks to mitigate this (would need 5-10 years of 24/6 production to fill govt. stockpiles).
raziel2p 6y ago
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 terms.
- jennyyang 6y ago
  I disagree. You need to treat the virus at the right level of concern otherwise you lose credibility. As we can all see, credibility from the experts needs to be maintained, otherwise no one trusts them anyone. The whole fiasco with masks is because the experts told us things that were obviously wrong at the beginning (ie. masks don't work, masks won't help regular people, etc). If there is airborne droplet transmission, which I believe is the case otherwise we wouldn't get such infectious spread in bars, etc, then we need to implement better ventilation, social distancing and mask wearing and probably goggles too. If it was truly "airborne", which it isn't, then the measures would need to be much, much more draconian otherwise it would spread much quicker.
  - raziel2p 6y ago
    > You need to treat the virus at the right level of concern otherwise you lose credibility. I agree with this but don't see how the use of the word "airborne" conveys concern. Maybe this is some american hollywood trope now that I remember reading the phrase "It's airborne!" in the original article? Wikipedia's article on airborne diseases certainly don't seem to imply that there's a strict definition of how long a pathogen has to survive in the air for it to be classified as airborne. > As we can all see, credibility from the experts needs to be maintained, otherwise no one trusts them anyone. While I agree with this, we're in an age of misinformation and macho power culture where saying "we're not sure yet so let's just be as careful as possible" apparently doesn't do much good in many places of the world. And I don't think a technically incorrect use of a word like airborne is NEARLY as significant as changing stances on masks and presidents endorsing quacks.
  - 6y ago
PopeDotNinja 6y ago
I propose calling airborne droplets “germ infested mouth farts”. It’d definitely get the 4 year olds on board.
- fermienrico 6y ago
  That's pretty disgusting and vulgar. Let's not.
- cultofmetatron 6y ago
  that's pretty disgusting and vulgar. I'm down!! :)
csours 6y ago
Is a better distinction Dry Airborne vs Wet Airborne? There is still particle size to consider I guess.
- droopyEyelids 6y ago
  Why don't you read the article? The distinction is between aerosols and droplets, in the case of corona virus, and by asking this question it looks like you're chasing the wild goose that OP brought into this thread.
  - csours 6y ago
    Up front: I am not a virologist; I am not saying these things are true, I am saying this is my understanding of this discussion. I am also not saying that Sars-Cov-2 can spread by small dry particles. I think there a 3 distinct things going on, at least. Large Wet Particles (droplets): easily caught by masks, fall quickly (3-6 feet), make surfaces infectious, cause infection by touch. Small Wet Particles (aerosol type 1): Hang in the air for at least 30 minutes. Infectious if breathed in. Mask is less effective (but not ineffective) Small Dry Particles (aerosol type 2): Hang in the air for 12 hours. Infectious if breathed in. Infectious by touch. Mask is less effective (but not ineffective). Most viruses are not viable as dry particles.
swsieber 6y ago
My friend uses "aerosols" for the latter term
SkyPuncher 6y ago
> 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 period of time (given the right circumstances). This nuance is challenging to convey. For healthcare workers, it's important because it likely means standard droplet based precautions are not enough. However, it also seems that full airborne precautions (PAPR's) are overkill. My take is N95's do enough to dehumidify droplets and ultimately break down particles. For the general public, the nuance is less important. Most don't have access to proper fitting N95 (or better) masks, so they're stuck wearing cloth or surgical masks. They should simply think of COVID as airborne because they're likely not wearing the proper gear.
- fuckyah 6y ago
  for most people <70 sars-cov-2 is not more dangerous than the flu. so mask wearing is not necessary. we'll get faster to herd immunity that way...
- prutschman 6y ago
  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?
  - lmilcin 6y ago
    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. Volume increases with cube while surface with square of diameter. When the droplet gets smaller the drying out speeds up. The only time there are persistent droplets of water in air is called fog and happens when air is supersaturated with water. This happens when you cool air that is already 100% humidity. In that circumstance water cannot evaporate and that is what makes it possible to have water droplets in air. Once the relative humidity falls below 100% even a tiny bit, the fog almost instantly disappears. Ability of virus to be airborne means it can survive outside droplet of bodily fluid for an extended period of time. Once all water dries out it also becomes very light and can be moved by smallest currents of air.
droopyEyelids 6y ago
The WHOLE POINT of the article is to educate you about the difference between droplets (ballistic) and aerosols (behave like a gas). It doesn't look like you, or the people replying to you read the article. And thats a shame, because you're exactly the type of person who the author is trying to educate.
- noahtallen 6y ago
  I believe that’s why the parent comment said scientists and medical experts should improve how they explain terms going forward. People like OP should not be this confused about how the virus spreads after 4 months of hearing about it all the time. I’m glad we have magazines helping fix that problem now, but communication from places like the CDC hasn’t been totally understandable to normal people. (Add a healthy dose of misinformation and propaganda and you get today’s situation :))
- dang 6y ago
  Please read and follow the site guidelines. You broke several of them here, and have been doing so elsewhere also. https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html
briandear 6y ago
> If coronavirus were truly airborne, then we would all need to wear masks all the time, even when no one is around. Cloth masks wouldn’t protect against that. Masks don’t do anything to stop airborne spread, only potentially mitigating droplet spread. Unless you are referring to biohazard respirators as “masks.”
gdubs 6y ago
This is a bit of an outdated view on Coronavirus though. The whole point is that “airborne” isn’t black and white (which is how the WHO has treated it) and is more of a spectrum. A large number of scientists have been lobbying the WHO to get them to talk about it as airborne because it’s not just heavy droplets like people thought in the beginning. And there’s real concern that viral load can build up in poorly ventilated spaces. Which is why it’s a good idea to spend as little time in closed public spaces as possible, and why Fauci suggests that if you’re someone who needs to avoid it at all costs, then goggles are probably a good idea.
jdlyga 6y ago
This is why science communicators are extremely important. Technical words are great for trained professionals who understand the context. But too many people, myself included, repeat these words only partially understanding what they're intended to mean.
echelon 6y ago
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.
- bsder 6y ago
  > The birth of the anti-mask movement, etc. Hogwash. Those people would have latched onto something else. The 1918 pandemic also had its "anti-mask" idiots. Stupid is timeless and universal. > You shouldn't lie to the public. Agreed. Calling an active pandemic a "liberal hoax" started a huge problem.
  - vkou 6y ago
    You are being unfairly downvoted. You are right in that the anti-mask movement did not start because the CDC reversed its position. (Thank you for citing 1918 as a supporting point.) The anti-mask movement started because everything in American politics has to be turned into a right-left culture war, regardless of whether the issue is actually controversial, or if it has a simple, obvious solution. The people leading the Covid denialist movement aren't stupid. They are just cynically scoring political points with their base.
ChuckMcM 6y ago
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-kills-airborne-coronaviruses 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.
woeirua 6y ago
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.
- chc 6y ago
  The messaging regarding masks was "They don't keep you from getting it, and everyone should be inside right now to avoid spreading it if they have it, so avoid buying a mask to make sure there are enough for people who need them." The messaging regarding masks now is, "They don't keep you from getting it, but they do stop you from spreading it, so since there are enough masks now for everyone, you should wear one." It doesn't seem like a flip-flop so much as responding to the current state of the world. I think the public's willingness to trust the experts has been undermined more by a large portion of the US government deliberately trying to undermine public trust in the experts.
  - gabaix 6y ago
    “When to use mask: - If you are healthy, you only need to wear a mask if you are taking care of a person with suspected #coronavirus infection. - Wear a mask if you are coughing or sneezing” WHO, Mar 1, https://twitter.com/who/status/1234095938555260929?s=21 https://twitter.com/who/status/1234095938555260929?s=21 “the wide use of masks by healthy people in the community setting is not supported by current evidence and carries uncertainties and critical risks.” WHO, Apr 6, https://apps.who.int/iris/handle/10665/331693 https://apps.who.int/iris/handle/10665/331693
    - chc 6y ago
      That second source goes on to point out that its major concern (in terms of "uncertainties and critical risks") is healthy people using medical masks in places where there isn't enough supply and depriving healthcare workers of them, like I said. It specifically does not advise against nonmedical masks, and simply notes that the WHO was still actively studying their use at the time and would make a recommendation when evidence was available. So the "flip-flop" here was the WHO saying "I don't know, I'm looking into it," and then later saying "I've looked into it and have some strong recommendations."

enraged_camel 6y ago

The article addresses this midway through. The problem is that even the experts haven't really agreed on terminology. They need to do that first before they can hope to inform the public. :)

mc32 6y ago
So why talk about HVAC systems ? Context: >” by 10 bottles of hand sanitizer without a word on ventilation—whether it was opening windows, employing upgraded filters in its HVAC systems, or using portable HEPA filters. It seems baffling that despite mounting evidence of its importance, we are stuck practicing hygiene theater...”
- enraged_camel 6y ago
  Sorry, what do you mean?
  - vladTheInhaler 6y ago
    I suspect the parent post meant "why not", as in "improving HVAC would be more effective than the omnipresent hand sanitizer, so why aren't we talking about that?"

mc32 6y ago

One important point that comes out of this is that few people are stressing shoe sole hygiene. Not necessarily meaning that one has to scrub them often, but to be mindful of what it touches (car interior mats, mats at home and possibly if people don’t take off their shoes, all over the house, hands taking off shoes, shoe racks, etc.) Given that droplets mean the virus will accumulate on floors and such surfaces.

dpeck 6y ago
A place to put outside shoes and put on inside slippers (flip flops in my case) is good for clean floors anyway. I highly recommend, whether that’s a little mudroom or just a walled rubber/plastic container to take off shoes. That said, I’m not sure it does much for this particular virus, but it can’t hurt and your floors (especially carpets, but those are nasty anyway) stay much cleaner.
dalyons 6y ago
why would that matter? transmission from surfaces is apparently quite low, and it doesnt last long on surfaces, and its not like im touching / eating off anything my shoes come into contact with anyway. This feels like an incredibly low risk vector
- mc32 6y ago
  Low but greater than the “aerosolized” vector. When people sneeze, it land on surfaces (like floors), when they cough, etc. If surfaces were not a problem, we wouldn’t be using wipes and sanitizers. So why ignore one possibility and stress another? When people take off their shoes they can get contaminated. If they have pets the pets will pick some up and get it on you, etc.
  - wk_end 6y ago
    The incessant use of wipes and sanitizers is basically "Hygiene Theatre" [1]. > In May, the Centers for Disease Control and Prevention updated its guidelines to clarify that while COVID-19 spreads easily among speakers and sneezers in close encounters, touching a surface “isn’t thought to be the main way the virus spreads.” Other scientists have reached a more forceful conclusion. “Surface transmission of COVID-19 is not justified at all by the science,” Emanuel Goldman, a microbiology professor at Rutgers New Jersey Medical School, told me. [1] https://www.theatlantic.com/ideas/archive/2020/07/scourge-hygiene-theater/614599/ https://www.theatlantic.com/ideas/archive/2020/07/scourge-hy...

jtbayly 6y ago

> 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 takes to completely eliminate this virus. They think it would be nice if the virus went away, but they are not working towards that as their goal.

jennyyang 6y ago
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 it is, and how quickly it can overrun a limited hospital system. Even at a sub-10% hospitalization rate for people younger than 60, we are seeing many hospitals getting full. It being truly airborne would make things worse by many orders of magnitude. The way coronavirus spreads is basically the same mechanism as the flu and the cold, yet the levels of people getting infected are much much worse. Imagine if simply walking through a room could get you infected. The spread would be undeniably worse than anything we had every seen before. Even stores like Costco and all factories would have to shut down. So yes, very strict lockdowns would need to be in place. Thank goodness it's not.
- mensetmanusman 6y ago
  Um.. it is airborne, that is why there are multiple super-spreader events that can’t be explained by someone interacting within 3-6 feet for 10 minutes. (e.g. cases of 1 to 100, 1:500 case reported as well). If you walked into an empty hospital room that was just used with high air-virion density, you could get infected, that is why they decontaminate with the equipment you see. I think the main reason this isn’t being communicated is because we will never have enough N95 masks to mitigate this (would need 5-10 years of 24/6 production to fill govt. stockpiles).

raziel2p 6y ago

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 terms.

jennyyang 6y ago
I disagree. You need to treat the virus at the right level of concern otherwise you lose credibility. As we can all see, credibility from the experts needs to be maintained, otherwise no one trusts them anyone. The whole fiasco with masks is because the experts told us things that were obviously wrong at the beginning (ie. masks don't work, masks won't help regular people, etc). If there is airborne droplet transmission, which I believe is the case otherwise we wouldn't get such infectious spread in bars, etc, then we need to implement better ventilation, social distancing and mask wearing and probably goggles too. If it was truly "airborne", which it isn't, then the measures would need to be much, much more draconian otherwise it would spread much quicker.
- raziel2p 6y ago
  > You need to treat the virus at the right level of concern otherwise you lose credibility. I agree with this but don't see how the use of the word "airborne" conveys concern. Maybe this is some american hollywood trope now that I remember reading the phrase "It's airborne!" in the original article? Wikipedia's article on airborne diseases certainly don't seem to imply that there's a strict definition of how long a pathogen has to survive in the air for it to be classified as airborne. > As we can all see, credibility from the experts needs to be maintained, otherwise no one trusts them anyone. While I agree with this, we're in an age of misinformation and macho power culture where saying "we're not sure yet so let's just be as careful as possible" apparently doesn't do much good in many places of the world. And I don't think a technically incorrect use of a word like airborne is NEARLY as significant as changing stances on masks and presidents endorsing quacks.
- 6y ago

PopeDotNinja 6y ago

I propose calling airborne droplets “germ infested mouth farts”. It’d definitely get the 4 year olds on board.

fermienrico 6y ago
That's pretty disgusting and vulgar. Let's not.
cultofmetatron 6y ago
that's pretty disgusting and vulgar. I'm down!! :)

csours 6y ago

Is a better distinction Dry Airborne vs Wet Airborne? There is still particle size to consider I guess.

droopyEyelids 6y ago
Why don't you read the article? The distinction is between aerosols and droplets, in the case of corona virus, and by asking this question it looks like you're chasing the wild goose that OP brought into this thread.
- csours 6y ago
  Up front: I am not a virologist; I am not saying these things are true, I am saying this is my understanding of this discussion. I am also not saying that Sars-Cov-2 can spread by small dry particles. I think there a 3 distinct things going on, at least. Large Wet Particles (droplets): easily caught by masks, fall quickly (3-6 feet), make surfaces infectious, cause infection by touch. Small Wet Particles (aerosol type 1): Hang in the air for at least 30 minutes. Infectious if breathed in. Mask is less effective (but not ineffective) Small Dry Particles (aerosol type 2): Hang in the air for 12 hours. Infectious if breathed in. Infectious by touch. Mask is less effective (but not ineffective). Most viruses are not viable as dry particles.

swsieber 6y ago

My friend uses "aerosols" for the latter term

SkyPuncher 6y ago

> 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 period of time (given the right circumstances). This nuance is challenging to convey. For healthcare workers, it's important because it likely means standard droplet based precautions are not enough. However, it also seems that full airborne precautions (PAPR's) are overkill. My take is N95's do enough to dehumidify droplets and ultimately break down particles. For the general public, the nuance is less important. Most don't have access to proper fitting N95 (or better) masks, so they're stuck wearing cloth or surgical masks. They should simply think of COVID as airborne because they're likely not wearing the proper gear.

fuckyah 6y ago
for most people <70 sars-cov-2 is not more dangerous than the flu. so mask wearing is not necessary. we'll get faster to herd immunity that way...
prutschman 6y ago
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?
- lmilcin 6y ago
  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. Volume increases with cube while surface with square of diameter. When the droplet gets smaller the drying out speeds up. The only time there are persistent droplets of water in air is called fog and happens when air is supersaturated with water. This happens when you cool air that is already 100% humidity. In that circumstance water cannot evaporate and that is what makes it possible to have water droplets in air. Once the relative humidity falls below 100% even a tiny bit, the fog almost instantly disappears. Ability of virus to be airborne means it can survive outside droplet of bodily fluid for an extended period of time. Once all water dries out it also becomes very light and can be moved by smallest currents of air.

droopyEyelids 6y ago

The WHOLE POINT of the article is to educate you about the difference between droplets (ballistic) and aerosols (behave like a gas). It doesn't look like you, or the people replying to you read the article. And thats a shame, because you're exactly the type of person who the author is trying to educate.

noahtallen 6y ago
I believe that’s why the parent comment said scientists and medical experts should improve how they explain terms going forward. People like OP should not be this confused about how the virus spreads after 4 months of hearing about it all the time. I’m glad we have magazines helping fix that problem now, but communication from places like the CDC hasn’t been totally understandable to normal people. (Add a healthy dose of misinformation and propaganda and you get today’s situation :))
dang 6y ago
Please read and follow the site guidelines. You broke several of them here, and have been doing so elsewhere also. https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html

briandear 6y ago

> If coronavirus were truly airborne, then we would all need to wear masks all the time, even when no one is around. Cloth masks wouldn’t protect against that. Masks don’t do anything to stop airborne spread, only potentially mitigating droplet spread. Unless you are referring to biohazard respirators as “masks.”

gdubs 6y ago

This is a bit of an outdated view on Coronavirus though. The whole point is that “airborne” isn’t black and white (which is how the WHO has treated it) and is more of a spectrum. A large number of scientists have been lobbying the WHO to get them to talk about it as airborne because it’s not just heavy droplets like people thought in the beginning. And there’s real concern that viral load can build up in poorly ventilated spaces. Which is why it’s a good idea to spend as little time in closed public spaces as possible, and why Fauci suggests that if you’re someone who needs to avoid it at all costs, then goggles are probably a good idea.

jdlyga 6y ago

This is why science communicators are extremely important. Technical words are great for trained professionals who understand the context. But too many people, myself included, repeat these words only partially understanding what they're intended to mean.

echelon 6y ago

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.

bsder 6y ago
> The birth of the anti-mask movement, etc. Hogwash. Those people would have latched onto something else. The 1918 pandemic also had its "anti-mask" idiots. Stupid is timeless and universal. > You shouldn't lie to the public. Agreed. Calling an active pandemic a "liberal hoax" started a huge problem.
- vkou 6y ago
  You are being unfairly downvoted. You are right in that the anti-mask movement did not start because the CDC reversed its position. (Thank you for citing 1918 as a supporting point.) The anti-mask movement started because everything in American politics has to be turned into a right-left culture war, regardless of whether the issue is actually controversial, or if it has a simple, obvious solution. The people leading the Covid denialist movement aren't stupid. They are just cynically scoring political points with their base.

ChuckMcM 6y ago

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-kills-airborne-coronaviruses 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.

woeirua 6y ago

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.

chc 6y ago
The messaging regarding masks was "They don't keep you from getting it, and everyone should be inside right now to avoid spreading it if they have it, so avoid buying a mask to make sure there are enough for people who need them." The messaging regarding masks now is, "They don't keep you from getting it, but they do stop you from spreading it, so since there are enough masks now for everyone, you should wear one." It doesn't seem like a flip-flop so much as responding to the current state of the world. I think the public's willingness to trust the experts has been undermined more by a large portion of the US government deliberately trying to undermine public trust in the experts.
- gabaix 6y ago
  “When to use mask: - If you are healthy, you only need to wear a mask if you are taking care of a person with suspected #coronavirus infection. - Wear a mask if you are coughing or sneezing” WHO, Mar 1, https://twitter.com/who/status/1234095938555260929?s=21 https://twitter.com/who/status/1234095938555260929?s=21 “the wide use of masks by healthy people in the community setting is not supported by current evidence and carries uncertainties and critical risks.” WHO, Apr 6, https://apps.who.int/iris/handle/10665/331693 https://apps.who.int/iris/handle/10665/331693
  - chc 6y ago
    That second source goes on to point out that its major concern (in terms of "uncertainties and critical risks") is healthy people using medical masks in places where there isn't enough supply and depriving healthcare workers of them, like I said. It specifically does not advise against nonmedical masks, and simply notes that the WHO was still actively studying their use at the time and would make a recommendation when evidence was available. So the "flip-flop" here was the WHO saying "I don't know, I'm looking into it," and then later saying "I've looked into it and have some strong recommendations."