Two mechanisms for accelerated diffusion of COVID-19 outbreaks in regions with high intensity of population and polluting industrialization: the air pollution-to-human and human-to-human transmission dynamics

Mario Coccia

should control health risks caused by bio aerosols during air pollution, especially for immunocompromised, elderly and other fragile individuals. This may explain the high mortality of certain individuals having previous pathologies because of in Italy that has the mortality rate (the percentage of deaths compared to the total of those who tested positive for COVID-19) of about 80% in individuals aged > 70 years with comorbidities as of April 1 st , 2020 (Istituto Superiore Sanità , 2020; cf., WHO, 2020c). Papi et al. (2006) also indicate that chronic obstructive pulmonary disease (COPD) was significantly exacerbated by respiratory viral infections that cause reduction of forced expiratory volume in 1s (FEV1) and airway inflammation (cf., Gorse et al., 2006) . report that the most prevalent viruses detected during acute exacerbations of COPD in Hong Kong were the influenza A virus and coronavirus. They indicate that among patients with a mean age of more than 75 years, mean FEV1 was 40% of predicted normal and the FEV1/FVC (forced vital capacity) ratio was reduced to 58% of normal. De Serres et al. (2009) also suggested that the influenza virus frequently causes acute exacerbations of asthma and COPD. Moreover, the study by Wei et al. (2020) argues that air pollution in coastal city Weihai in China was slightly lower than the inland city of Jinan. This study supports our results that the viral infectivity by COVID-19 is higher in hinterland cities rather than coastal cities in Italy. Wei et al. (2020, p. 9 ) also suggest that different air quality strategies should be applied in inland and coastal cities: coastal cities need start bio aerosol risk alarm during moderate pollution when severe pollution occurs in inland cities.