> Schools could install air purifiers for a few hundres bucks per room and greatly reduce infections That may be true for teenagers and up and perhaps more cro

> Schools could install air purifiers for a few hundres bucks per room and greatly reduce infections That may be true for teenagers and up and perhaps more crowded workplaces or university halls. But I think you are greatly underestimating how nasty and excessively touchy most kindergarten and primary school kids are, that really is not fixable with just HEPA filters. Kids will always be a bio-hazard agglomerate of disease vectors it is kind of unavoidable when you put them all together.