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Associations between Air Quality and Covid-19 Infection

Air pollution has been an urgent trouble for many regions. The clear relationship between various types of air pollution and COVID-19 cases has not been well understood. The particulate matter (PM), as an air pollutant, was found to act as a potential carrier of the SARS-CoV-2 virus. It might also cause higher angiotensinconverting enzyme 2 (ACE2) activation when inducing airway inflammation, and eventually increase the risk of COVID-19 infection. By concluding some of the existing studies, the statistical correlations between air pollutants and COVID-19 infection can be visualised, such as positive correlations found between PM2.5, PM10, NO2, etc. and COVID-19 infection, while negative correlations with SO2, as well as some controversial findings on O3, etc. Further research is required to address possible mechanisms of how PM might facilitate the spreading of COVID-19. Monitoring air pollution levels and applying comprehensive models for analysing associations between COVID-19 infection and air pollution appear to be useful for further studies.