The JAMA Network Open | Original investigation ! | 20 April 2022
The findings of this study suggest that air pollution may play a role in COVID-19 and support the potential benefit of reducing air pollutant levels These findings suggest that air pollution may play a role in COVID-19 and support the potential benefit of reducing air pollutant levels..

https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2791305