The influence of air pollutants on COVID-19 severity in the administrative and industrial city of Kharkiv

Abstract

Background. Despite the official statement by the World Health Organization regarding the end of coronavirus disease (COVID-19) pandemic, the risk of an epidemic rise in morbidity remains due to the active circulation of the pathogen and its mutation. Social, natural, environmental, and other factors can contribute to the spread of COVID-19. Air pollutants are extremely dangerous for humans, and a mixture of aerosols and dust particles in the air can serve as factors for the severe acute respiratory syndrome coronavirus 2 transmission. So, the purpose of the study was to reveal the impact of air pollutants on COVID-19 severity in Kharkiv. Materials and methods. The influence of environmental factors on the manifestations of COVID-19 epidemic was assessed for 425 days. 16,723 cases of hospitalizations, 1,883 deaths, and 15,146 confirmed cases of COVID-19 in various age groups were studied. There were on average 4,663 active cases every day. Statistical analysis on assessing the impact of environmental factors on COVID-19 morbidity with different degrees of severity was performed using the non-parametric Kruskal-Wallis test in the IBM SPSS Statistics software package, and the normality of the distribution was checked using the Kolmogorov-Smirnov test. Microsoft Office Excel 2016 spreadsheet tools were used for some auxiliary calculations and graphing. Results. The influence of sulfur dioxide, nitrogen dioxide, nitrous oxide, hydrogen sulfide, phenol, soot, and formaldehyde on COVID-19 morbidity in different severity of infection course with incubation periods of 3–4, 6–7, and 10–14 days was revealed. The effect of high concentrations of nitrogen dioxide, nitrogen oxide, and formaldehyde was most significant on active, confirmed, hospitalized, and fatal cases of COVID-19. At the same time, a rise in active cases of COVID-19 was observed with increasing concentrations of sulfur dioxide and hydrogen sulfide, and high concentrations of phenol and soot had an impact on severe forms. Conclusions. Air pollution can contribute to the spread of COVID-19 and lead to its severe forms, which should be considered when predicting morbidity at different levels (national, regional, local) of epidemiological surveillance. Further research is needed to reveal causal relationships between the incidence of COVID-19 and air pollutants, considering the influence of social and natural factors.