Machine learning reveals that prolonged exposure to air pollution is associated with SARS-CoV-2 mortality and infectivity in Italy

Abstract

Air pollution can increase the risk of respiratory diseases, enhancing the susceptibility to viral and bacterial infections. Some studies suggest that small air particles facilitate the spread of viruses and also of the new coronavirus, besides the direct person-to-person contagion. However, the effects of the exposure to particulate matter and other contaminants on SARS-CoV-2 has been poorly explored. Here we examined the possible reasons why the new coronavirus differently impacted on Italian regional and provincial populations. With the help of artificial intelligence, we studied the importance of air pollution for mortality and positivity rates of the SARS-CoV-2 outbreak in Italy. We discovered that among several environmental, health, and socio-economic factors, air pollution and fine particulate matter (PM2.5), as its main component, resulted as the most important predictors of SARS-CoV-2 effects. We also found that the emissions from industries, farms, and road traffic - in order of importance - might be responsible for more than 70% of the deaths associated with SARS-CoV-2 nationwide. Given the major contribution played by air pollution (much more important than other health and socio-economic factors, as we discovered), we projected that, with an increase of 5–10% in air pollution, similar future pathogens may inflate the epidemic toll of Italy by 21–32% additional cases, whose 19–28% more positives and 4–14% more deaths. Our findings, demonstrating that fine-particulate (PM2.5) pollutant level is the most important factor to predict SARS-CoV-2 effects that would worsen even with a slight decrease of air quality, highlight that the imperative of productivity before health and environmental protection is, indeed, a short-term/small-minded resolution.

COVID-19 and Air Pollution: Measuring Pandemic Impact to Air Quality in Five European Countries

“…For instance, the highest concentration of confirmed COVID-19 cases was in Northern Italy, the Po valley to be exact, where the five Italian cities with the highest pollution levels are found [65][66][67]. Although some studies have found spatial coincidence among air pollution and high incidence and mortality [38][39][40][41]50,[65][66][67][68], there is a larger uncertainty and further epidemiological research is needed. Figure 3 shows the concentration of NO 2 , PM 2.5 , and PM 10 changes in Europe in the two different periods: 6 January 2020 data before the outbreak of COVID-19 and 31 March 2020, when most of Europe introduced national lockdowns.…”

The role of airborne particles and environmental considerations in the transmission of SARS-CoV-2

“…Studies have shown that the high infection rate of COVID-19 is related to poor air quality ( Cazzolla Gatti et al, 2020 , Coccia, 2020 , Conticini et al, 2020 ). Air pollution can cause inflammations, cell damage, and respiratory diseases ( Shao et al, 2017 , Feng et al, 2020 , Rao et al, 2020 , Wang et al, 2021 ).…”

“…Another study observed two regions in Europe, Lombardy, and Emilia-Romagna, which have the highest mortality rate of the virus in the World and are typified by the most polluted area in Europe ( Conticini et al, 2020 ). Cazzolla Gatti et al (2020) also believed that PM 2.5 was related to transmission dynamics and the infectivity of SARS-CoV-2. They projected that, with an increase of 5%–10% in air pollution, similar future pathogens may inflate the epidemic toll of Italy by 21%–32% ( Cazzolla Gatti et al, 2020 ).…”

“… Cazzolla Gatti et al (2020) also believed that PM 2.5 was related to transmission dynamics and the infectivity of SARS-CoV-2. They projected that, with an increase of 5%–10% in air pollution, similar future pathogens may inflate the epidemic toll of Italy by 21%–32% ( Cazzolla Gatti et al, 2020 ). In 235 Chinese cities, the relationship between short-term exposure to air pollution and daily confirmed cases were assessed, revealing a positive relationship ( Zhang et al, 2021 ).…”

Contribution of machine learning approaches in response to SARS-CoV-2 infection

“…According to Ref. [ 32 ], a rise of 5–10% in air pollution would result in 21–32% new cases and eventually leading to 4–14% more deaths.…”