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Rapid response to:


Covid-19: a puzzle with many missing pieces

BMJ 2020; 368 doi: (Published 19 February 2020) Cite this as: BMJ 2020;368:m627

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Clinical findings in a group of patients infected with the 2019 novel coronavirus (SARS-Cov-2)

Rapid Response:

Covid-19 and air pollution

Dear Editor

There is a common denominator to most countries and areas in each country with major cases of severe Covid-19 infection, China, South Korea, Iran, and northern Italy. This shared risk factor is a high air quality index. Air pollution has been associated with increase occurrence of respiratory tract infections (1-6).

Recent research has applied a time series analysis model to study the possible association between different types of air pollution and respiratory hospital admission in Shenzhen in 2013 (7). The study concluded that short-term exposure to ambient air pollution was associated with acute respiratory infection hospital admission.

We hope a study on exposure–response relationship between air pollutant concentrations and Covid-19 cases during the epidemic/pandemic outbreak will show if this risk factor has played a relevant role.

Giovanni Ghirga MD
International Society of Doctors for the Environment (Italy)

1. Ciencewicki J, Jaspers I. Air pollution and respiratory viral infection. Inhal Toxicol 2007;19:1135–1146.
2. Horne BD, Joy EA, Hofmann MG, Gesteland PH, Cannon JB, Lefler JS, et al. Short-term elevation of fine particulate matter air pollution and acute lower respiratory infection. Am J Respir Crit Care Med 2018; 198:759–766.
3. Neupane B, Jerrett M, Burnett RT, Marrie T, Arain A, Loeb M. Long-term exposure to ambient air pollution and risk of hospitalization with community-acquired pneumonia in older adults. Am J Respir Crit Care Med 2010;181:47–53.
4. Pirozzi CS, Jones BE, VanDerslice JA, Zhang Y, Paine R III, Dean NC.
5. Short-term air pollution and incident pneumonia: a case-crossover study. Ann Am Thorac Soc 2018;15:449–459.
6. Cohen AJ, Brauer M, Burnett R, Anderson HR, Frostad J, Estep K, et al.
7. Xiaolin Xia, An Zhang, Shi Liang, Qingwen Qi, Lili Jiang, and Yanjun Ye. The Association between Air Pollution and Population Health Risk for Respiratory Infection: A Case Study of Shenzhen, China. Int. J. Environ. Res. Public Health 2017, 14, 950; doi:10.3390/ijerph14090950.

Competing interests: No competing interests

26 February 2020
Giovanni Ghirga
Chief of Pediatrics
International Society of Doctors for the Environment (Italy)
Via Adua 9C Civitavecchia Italy