Abstract
Studies have pointed out that air pollution may be a contributing factor to the coronavirus disease 2019 (COVID-19) pandemic. However, the specific links between air pollution and severe acute respiratory syndrome-coronavirus-2 infection remain unclear. Here we provide evidence from in vitro, animal and human studies from the existing literature. Epidemiological investigations have related various air pollutants to COVID-19 morbidity and mortality at the population level, however, those studies suffer from several limitations. Air pollution may be linked to an increase in COVID-19 severity and lethality through its impact on chronic diseases, such as cardiopulmonary diseases and diabetes. Experimental studies have shown that exposure to air pollution leads to a decreased immune response, thus facilitating viral penetration and replication. Viruses may persist in air through complex interactions with particles and gases depending on: 1) chemical composition; 2) electric charges of particles; and 3) meteorological conditions such as relative humidity, ultraviolet (UV) radiation and temperature. In addition, by reducing UV radiation, air pollutants may promote viral persistence in air and reduce vitamin D synthesis. Further epidemiological studies are needed to better estimate the impact of air pollution on COVID-19. In vitro and in vivo studies are also strongly needed, in particular to more precisely explore the particle–virus interaction in air.
Abstract
Our review highlights that both short- and long-term exposures to air pollution may be important aggravating factors for SARS-CoV-2 transmission and COVID-19 severity and lethality through multiple mechanisms https://bit.ly/395aS9w
Footnotes
Provenance: Submitted article, peer reviewed
Author contributions: T. Bourdrel conceived the idea for the review. T. Bourdrel designed and undertook the literature review and extracted the data with help from I. Annesi-Maesano and M-A. Bind. T. Bourdrel wrote the first draft of the manuscript with input from I. Annesi-Maesano and M-A. Bind. I. Annesi-Maesano synthesised this review. T. Bourdrel created the drawings and pictures. B. Alahmad and C.N. Maesano reviewed, edited and provided insights on the overall manuscript.
Conflict of interest: T. Bourdrel has nothing to disclose.
Conflict of interest: I. Annesi-Maesano has nothing to disclose.
Conflict of interest: B. Alahmad has nothing to disclose.
Conflict of interest: C.N. Maesano has nothing to disclose.
Conflict of interest: M-A. Bind has nothing to disclose.
Support statement: Research reported in this publication was supported by the John Harvard Distinguished Science Fellow Program within the FAS Division of Science of Harvard University, and by the Office of the Director, National Institutes of Health under Award Number DP5OD021412. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. Funding information for this article has been deposited with the Crossref Funder Registry.
- Received July 27, 2020.
- Accepted December 11, 2020.
- Copyright ©ERS 2021
This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial Licence 4.0.