China now manufactures ventilation ducts with silicon coating (which cuts the life of the virus considerably, perhaps as much as 2-3 hours vs 7 days). China also employs HEPA filters more commonly in ventilation systems for big factories, hospitals and some apartment buildings. People wear masks routinely. I don't know much about their subways and mass transit, but since many wear masks (not surgical masks), I'm sure that helps.
Ventilation is such a large concern that I consider the shared air in most American classroom buildings to be an enormous risk. Kids, of course, will end up being fine (3 deaths in 50,000,000? less than other causes of death in kids, for sure). But universities and colleges have a very different problem.
As do malls, restaurants, gyms, doctors' offices, etc.
Subways lack the basics of airplanes (most commercial airlines do have HEPA filtration). They are death traps and we're seeing France's plateau remain high, IMO, because of subways. New York is the same way.
An aside here: agencies are getting more slow and intermittent in their data submissions to the CDC/own national agencies because workers cannot continue to work 12 hour shifts, 30 days a year. There will be lags in data, which people will interpret as good news. The only good news on that front would be a systematic use of resources to test and report accurately.