The paper ( https://www.economist.com/science-and-technology/2020/03/26/airborne-particles-may-be-assisting-the-spread-of-sars-cov-2?fsrc=scn/fb/te/bl/ed/thepandemicairborneparticlesmaybeassistingthespreadofsarscov2scienceandtechnology) by Leonardo Setti of the University of Bologna and his colleagues show that there is the possibility that the catalyst of COVID 19 transmission is pollution—specifically, small airborne particles that might carry the virus on their surfaces. It is not yet 100% proven. But there are evidences that people exposed to heavy air pollution will suffer more serious consequences from COVID 19.
Either way, though, by reducing particles we can find an alternative way (to social distancing) to solve the crisis.
Nature-base solutions (NBS) can be one of the option to apply in all the big cities- hot spots of the COVID -19.
Let create an easy to insole NBS air cleaning prototype stations? May be something similar to http://www.rfi.fr/en/france/20170904-fighting-urban-air-pollution-microalgae?