Comment by ggdG

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. [...]