Opinion | Your Building Can Make You Sick or Keep You Well (Published 2020)
Proper ventilation, filtration and humidity reduce the spread of pathogens like the new coronavirus.
Interesting read about virus spread as people 'return to work' in open plan offices during what is heatwave season. The usual advice in offices and hospitals is to relocate to cooler parts of the building, but this is unlikely given distancing measures.
Considerations seem to be:
If outdoor air is brought in as part of building ventilation then it's preferable.
Air conditioning with only recirculating air means a low air exchange rate, as such a very low dilution of indoor aerosols
The lower humidity brought by Air Conditioning may help, but some viruses actually like a reduced humidity.