From: El Paso, TX
AFAIK and remembering/interpreting what I have heard in those interviews with experts, they look at droplets coughed out but also just at the plain old exhalation from an infected person. Certainly cover your own coughs, and certainly wash your hands, but one of the experts stressed multiple times that so far the evidence was (always might be new evidence by now) that the primary means of transmission was simply breathing.
One of them commented on what he judged the really bad idea of keeping the passengers on cruise ships with infected passengers, because cruise ships (as he said it) are notorious for recirculating the air through the passenger cabins. They (as he said it) basically insured more people would become infected, and IIRC he even termed it a form of torture.
So, I'm sure you can catch it by other means too, but it seems (IIRC) the most insidious route is simply an infected person breaths out and a non-infected person breaths in enough of that, then becomes infected.
That's the sort of thing the media loves to do, take pieces of a scientific study out of context, thus generating more fear and panic (literally their bread and butter). Let's see what the authors of that study really said and did:
First we get the scary headline:
The novel coronavirus SARS-CoV-2 can survive in the air for several hours in fine particles known as aerosols, according to preliminary research.
Now the details (but not the important ones):
The coronavirus, which causes the respiratory infection COVID-19, can be detected up to 3 hours after aerosolization and can infect cells throughout that time period, the study authors found. However, the study, first posted March 10 on the preprint database medRxiv, is still preliminary, because it has not undergone extensive peer-review. The authors did receive comments from one prospective scientific journal, and posted an updated version of the study on March 13 reflecting the revisions.
Assuming these initial results hold up to scrutiny, aerosol transmission of SARS-CoV-2 appears "plausible," the authors wrote
So it's "plausible", but.....
Morris and his colleagues tested whether viral particles from aerosols could infect cells grown in the lab, not actual human beings. More important, even if aerosol transmission can occur, it's unlikely to be the primary force driving the current pandemic, Morris added.
"The current scientific consensus is that most transmission via respiratory secretions happens in the form of large respiratory droplets ... rather than small aerosols," he said. "Droplets, fortunately, are heavy enough that they don't travel very far" and instead fall from the air after traveling only a few feet.
Maybe we should look at the actual test:
To see how long SARS-CoV-2 survives as an aerosol, the researchers fed samples of the virus through a nebulizer and sprayed the aerosolized particles into a drum-like structure. They then took periodic samples from the drum and analyzed each one for viral genetic material, known as RNA.
The team was able to detect viral RNA throughout the course of their 3-hour experiment, but that alone does guarantee that the remaining virus was viable.
OK, so artificially created aerosols can spread the virus in a lab. But here's the REAL question. Do humans send out virus-infected aerosol plumes?
The notion of viral particles hanging in the air, ready to infect passersby, may seem scary, but to become an aerosol, droplets containing viral particles must first be transformed into a light mist, thin enough to be supported by the air. By definition, aerosols are less than 0.0002 inches (5 microns) in diameter, while typical respiratory droplets exceed this size.
"Based on what we know about other respiratory viruses, we don't think that SARS-CoV-2 gets aerosolized in everyday settings," Morris said. "Rather, aerosolization, if it happens at all for SARS-CoV-2, is likely to happen in health care settings," according to recent studies, Morris said.
Hmmm. It can happen, but not in "everyday settings". Maybe it's just me, but that sounds like an important caveat, yes? So when do humans create aerosolized plumes?
During the SARS outbreak in 2002-2003, aerosols drove severe bouts of viral spread in health care settings, Gordon said.
Specifically, the use of intubation — where a tube is inserted into a patient's windpipe — and nebulizers — which transform medicines into an inhalable mist — generated aerosols and increased the risk of viral transmission to health care providers, she said.
So all a person has to do is steer clear of operating rooms during intubation, and they have nothing to worry about? That seems doable. However there is one other method for releasing aerosols, although this one does NOT involve normal people, breathing normally:
Additionally, aerosols released in stool likely drove two SARS superspreader events in non-health care settings, one in an apartment complex and the other in a hotel, she said.
Gee, that sounds familiar. If only somebody would post more information on that!
Next up, I'll address the "airborne circulation on cruise ships" canard.