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Comment by CamperBob2

1 year ago

(Shrug) I don't require scientific proof of the inverse-square law. It's self-evident to the point of being axiomatic. Standing 6 feet away from a virus source will expose you to about 44% fewer virus particles than standing 5 feet away from one, while not imposing any real hardships in most public interaction scenarios. What's controversial about that?

If you demand precise scientific rigor in all aspects of everyday life, public health is probably not the career field for you.

The same with masks:

Put a water hose on mist and spray someone with it. Then put a cloth over the nozzle and try to spray them. It's self evident yet people just could not grasp it.

[flagged]

  • Generally, after asserting that someone is drastically wrong, the next few paragraphs should be about backing that claim up with convincing evidence and explanations. Instead you digressed into talking about droplets vs aerosols and forgot to even make a connection between that and the "drastically wrong" take you were replying to.

    • Here's some serious research, spanning one year. Note how the confidence increases throughout time. You can't blame nvm0n2 for taking for granted what is already well-established since three years.

      --> May 2020: "How Coronavirus Spreads through the Air: What We Know So Far"

      https://www.scientificamerican.com/article/how-coronavirus-s...

      >For months, the U.S. Centers for Disease Control and Prevention and the World Health Organization have maintained that the novel coronavirus is primarily spread by droplets from someone who is coughing, sneezing or even talking within a few feet away. But anecdotal reports hint that it could be transmissible through particles suspended in the air (so-called "aerosol transmission"). And the WHO recently reversed its guidance to say that such transmission, particularly in “indoor locations where there are crowded and inadequately ventilated spaces where infected persons spend long periods of time with others, cannot be ruled out.”

      >Even if aerosols do not travel farther than most droplets, the oft-touted “six-foot rule” for social distancing may depend on the circumstances, Cowling says. If there is a fan or air conditioner, infectious aerosols (or even droplets, as was suspected in the case of that restaurant in China) could potentially sicken someone farther away who is downwind.

      --> October 2020: "Airborne transmission of SARS-CoV-2"

      https://www.science.org/doi/10.1126/science.abf0521

      >Viruses in droplets (larger than 100 µm) typically fall to the ground in seconds within 2 m of the source and can be sprayed like tiny cannonballs onto nearby individuals. Because of their limited travel range, physical distancing reduces exposure to these droplets. Viruses in aerosols (smaller than 100 µm) can remain suspended in the air for many seconds to hours, like smoke, and be inhaled. They are highly concentrated near an infected person, so they can infect people most easily in close proximity. But aerosols containing infectious virus (2) can also travel more than 2 m and accumulate in poorly ventilated indoor air, leading to superspreading events (3).

      >Individuals with COVID-19, many of whom have no symptoms, release thousands of virus-laden aerosols and far fewer droplets when breathing and talking (4–6). Thus, one is far more likely to inhale aerosols than be sprayed by a droplet (7), and so the balance of attention must be shifted to protecting against airborne transmission. In addition to existing mandates of mask-wearing, social distancing, and hygiene efforts, we urge public health officials to add clear guidance about the importance of moving activities outdoors, improving indoor air using ventilation and filtration, and improving protection for high-risk workers (8).

      --> May, 2021: "Ten scientific reasons in support of airborne transmission of SARS-CoV-2"

      https://www.thelancet.com/article/S0140-6736(21)00869-2/full...

      > First, superspreading events account for substantial SARS-CoV-2 transmission; indeed, such events may be the pandemic's primary drivers. [...]

      > Second, long-range transmission of SARS-CoV-2 between people in adjacent rooms but never in each other's presence has been documented in quarantine hotels. [...]

      > Third, asymptomatic or presymptomatic transmission of SARS-CoV-2 from people who are not coughing or sneezing is likely to account for at least a third, and perhaps up to 59%, of all transmission globally and is a key way SARS-CoV-2 has spread around the world [...]

      > Fourth, transmission of SARS-CoV-2 is higher indoors than outdoors and is substantially reduced by indoor ventilation.5 Both observations support a predominantly airborne route of transmission.

      > Fifth, nosocomial infections have been documented in health-care organisations, where there have been strict contact-and-droplet precautions and use of personal protective equipment (PPE) designed to protect against droplet but not aerosol exposure.

      > Sixth, viable SARS-CoV-2 has been detected in the air. In laboratory experiments, SARS-CoV-2 stayed infectious in the air for up to 3 h with a half-life of 1·1 h. [...]

      > Seventh, SARS-CoV-2 has been identified in air filters and building ducts in hospitals with COVID-19 patients; such locations could be reached only by aerosols.

      > Eighth, studies involving infected caged animals that were connected to separately caged uninfected animals via an air duct have shown transmission of SARS-CoV-2 that can be adequately explained only by aerosols.

      > Ninth, no study to our knowledge has provided strong or consistent evidence to refute the hypothesis of airborne SARS-CoV-2 transmission. [...]

      > Tenth, there is limited evidence to support other dominant routes of transmission—ie, respiratory droplet or fomite. [...]

    • Thank you to sibling ggdG for presenting even more evidence.

      But I don't get your reply at all, wtallis. "the next few paragraphs should be about backing that claim up with convincing evidence and explanations" - which is what the stuff about the Diamond Princess, SARS-1 and Hong Kong was about? Evidence and explanations for why the droplet model was wrong. Do you see that? The connection is that the claim exposure as simple as inverse square law on distance assumes no aerosol transmission, which is incorrect.

      It's hard not to feel that if people didn't keep flagging these kinds of discussions off the front pages, the wider HN community would be aware of all these basic facts which as the sibling post points out, is actually not controversial and hasn't been for years. HN is supposed to be about intellectual curiousity but the aggressive flagging behavior talked about by others in this thread means that too many posters here are stuck in a timewarp where it's still Jan 2020.

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