If I live in a high-rise, then there are large problems in avoiding elevators that could be worse. If all residents were to use stairs, aside from cardiac difficulties of some, mobility issues, risks of falling when carrying large loads, etc, there’s also going to be great amounts of aerosols generated by the huffing and puffing of many people using the stairs all day long (possibly in close proximity for multiple people going up at the same time). This could be a far larger vector as you’d be in the stairwell longer than you’d be in an elevator (https://www.cdc.gov/coronavirus/2019-ncov/php/public-health-... suggests 15 minutes of exposure needed).

It’s not clear that “avoid elevators” is universally less harmful. Also given the 15 minutes suggested it’s not clear that elevators by default pose a risk, and the large numbers in use in the world make it surprising if they are indeed a major vector but are otherwise undocumented or not part of suggested guidelines thus far.

I’m asking for evidence which shows they are indeed a risk factor, which should also hopefully take into consideration mask usage and number of stories. This would be extremely useful for people to factor in if they need to move, for example.