National Geographic in August has an important article by Maya Wet-Haas, “What ‘airborne transmission’ means, and how to protect yourself”, link.
Recent research suggests that as water in aerosols evaporates, even tinier droplets could be transmitted for further distances and through some masks, beyond the CDC gold standard of 6 feet.
But it is not clear if the concentrations would normally be enough to cause disease or real infection. On the other hand, the recent studies could cause real concerns about the ventilation in indoor spaces, like schools and even apartment buildings. It could also lead to narrowing of mask recommendations and requirements, even for civilians.
The article makes more comparisons of coronavirus transmissibility to other diseases, included measles and chickenpox.
Apoorva Mandavelli has a similar "smoking gun" article in the New York Times today about aerosol in hospitals.
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