Fig. 1

Air pollutant exposure can increase the vulnerability towards adverse COVID-19 health outcomes. By long-term (10 to 2 years) exposure the induction of chronic diseases are known risk factors for COVID-19 infection, morbidity and mortality. In the short-term (28 to 7 days) exposure, air pollutants might increase COVID-19 vulnerability by inducing an inflammatory response in the lung tissue and the human body. Finally, as SARS-CoV2 can adhere to small particulate matter in the air, this might also increase COVID-19 incidence within very short-term exposure up to 48 h