HIV/AIDS is a bit more important because the disease can lag the infection by a large period.
You are wrong. Read:
1. https://www.who.int/news-room/commentaries/detail/transmissi....
2. https://www.nature.com/articles/s41586-020-2342-5_reference.....
Aerosol transmission is the main vector.
Consider posing your statement in the reverse: SARS-CoV-2 does not disperse in droplets, and/or is not infectious when not in a droplet. There is no reason to believe either of those things!
It's totally reasonable to assume the virus could separate from a droplet and would remain infectious by itself for enough time to infect someone. This is common in other viruses, and seems to make sense from first principles. Why would virus particles not be able to form aerosols?
Are you really prepared to make the bet that they aren't infectious?
It's my understanding that most don't spread in this fashion. If you're hospitalized with cold/flu, your care team will observe droplet precautions, not aerosol ones.
If you have measles, which spreads via aerosol, they'll be using substantially more gear. The aerosol transmission is also why measles is shockingly easy to spread versus most other diseases.
>The physics of exhaled air and flow physics have generated hypotheses about possible mechanisms of SARS-CoV-2 transmission through aerosols.(13-16) These theories suggest that 1) a number of respiratory droplets generate microscopic aerosols (<5 µm) by evaporating, and 2) normal breathing and talking results in exhaled aerosols. Thus, a susceptible person could inhale aerosols, and could become infected if the aerosols contain the virus in sufficient quantity to cause infection within the recipient. However, the proportion of exhaled droplet nuclei or of respiratory droplets that evaporate to generate aerosols, and the infectious dose of viable SARS-CoV-2 required to cause infection in another person are not known, but it has been studied for other respiratory viruses.(17)
What the WHO and some doctors are doing is going: "despite the fact that it seems like it can spread via aerosols and that seems fairly likely, we want hard proof and are willing to risk our lives on that basis."
So, lol.
From my understanding, part of this is because most hospitals don't have aerosol specific precautions. Pre-COVID, anything requiring more than droplet precautions was simply handled with full-airborne precautions (negative pressure room, PAPR, etc).
Ideally, we'd have the airborne-precaution PPE for all COVID care but that's extremely expensive and leadership (hospital and gov't) have become aware that healthcare workers will still show up to work even without proper protection.
> To date, transmission of SARS-CoV-2 by this type of aerosol route has not been demonstrated; much more research is needed given the possible implications of such route of transmission.
That seems to be in direct opposition to your statement, correct? Or am I missing something.
The thing is -- why assume it can't form aerosols and that those aerosols aren't infectious? By demanding evidence for aerosol formation that is what they are stating. It makes no sense. Most viruses do form aerosols, and those aerosols do seem to be infectious.
By strict definition, aerosol is not airborne. The behaviors converge, but there is a technical difference. It's particularly important when it comes to designing effective filtering material and sanitization processes.
To me the only thing that was clear was the definition of airborne is not standard.
By strict definition, COVID is not airborne since it seems to require a host material (e.g. water droplet). This is in contrast to measles which individual virus particles can survive without a host material. Practically speaking though, COVID seems to be able to survive well in such small droplets that it acts like an airborne disease.
At a public health, COVID might as well be treated as airborne. Within acute care settings, this is a critical difference is being used as justification that a _properly_ fitted N95 and eye covering is sufficient to care for COVID patients. If COVID was truly airborne, all patient care should require airborne-level PPE (like PAPRs).