Micro- and macroclimate factors certainly have more influence on our health than being reflected by current research. A new PLOS study now finds that

facilities built more than 50 years ago, characterised by large windows and high ceilings, had greater ventilation than modern naturally ventilated rooms (40 versus 17 air changes per hour) … Old-fashioned clinical areas with high ceilings and large windows provide greatest protection. Natural ventilation costs little and is maintenance free.