Fig. 3.

Air pollution (HAD) effects for COVID-19 spread in (a) and mortality in (b). In (a) the blue line represents the effect of air pollution on COVID-19 spread and the upper and lower bands represent the 95%CI. Equivalently in (b) for COVID-19 mortality evolution, the effect and bands appear in color orange. The COVID-19 spread and mortality units are based on rates via the offset as produced by the related models. (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)