Air Pollution and Influenza: A Systematic Review and Meta-Analysis

Rui  Sun; Juan  Tao; Na  Tang; Zhijun  Chen; Xiaowei  Guo; Lianhong  Zou; Junhua  Zhou

doi:10.18502/ijph.v53i1.14678

Rui Sun Key Laboratory of Molecular Epidemiology of Hunan Province, School of Medicine, Hunan Normal University, Changsha, 410013, Hunan, China
Juan Tao Key Laboratory of Molecular Epidemiology of Hunan Province, School of Medicine, Hunan Normal University, Changsha, 410013, Hunan, China
Na Tang Key Laboratory of Molecular Epidemiology of Hunan Province, School of Medicine, Hunan Normal University, Changsha, 410013, Hunan, China
Zhijun Chen Key Laboratory of Molecular Epidemiology of Hunan Province, School of Medicine, Hunan Normal University, Changsha, 410013, Hunan, China
Xiaowei Guo Key Laboratory of Molecular Epidemiology of Hunan Province, School of Medicine, Hunan Normal University, Changsha, 410013, Hunan, China
Lianhong Zou Hunan Provincial People's Hospital (The First Affiliated Hospital of Hunan Normal University), Changsha, Hunan 410013, P.R. China
Junhua Zhou Key Laboratory of Molecular Epidemiology of Hunan Province, School of Medicine, Hunan Normal University, Changsha, 410013, Hunan, China

DOI: https://doi.org/10.18502/ijph.v53i1.14678

Keywords: Influenza-like illness; Air pollutants; Meta-analysis

Abstract

Background: Influenza is the first infectious disease that implements global monitoring and is one of the major public health issues in the world. Air pollutants have become an important global public health issue, in recent years, and much epidemiological and clinical evidence has shown that air pollutants are associated with respiratory diseases.

Methods: We comprehensively searched articles published up to 15 November 2022 in PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), Database of Chinese sci-tech periodicals, and Wanfang Database. The search strategies were based on keyword combinations related to influenza and air pollutants. The air pollutants included particulate matter (PM_2.5, PM₁₀), nitrogen dioxide (NO₂), sulfur dioxide (SO₂), carbon monoxide (CO), and ozone (O₃). Meta-analysis was performed using the R programming language (R4.2.1).

Results: A total of 2926 records were identified and 1220 duplicates were excluded. Finally, 19 studies were included in the meta-analysis according to inclusion and exclusion criteria. We observed a significant association between partial air pollutants (PM_2.5, NO₂, PM₁₀ and SO₂) and the incidence risk of influenza. The RRs were 1.0221 (95% CI: 1.0093~1.0352), 1.0395 (95% CI: 1.0131~1.0666), 1.007 (95% CI: 1.0009~1.0132), and 1.0352 (95% CI. 1.0076~1.0635), respectively. However, there was no significant relationship between CO and O₃ exposure and influenza, and the RRs were 1.2272 (95% CI: 0.9253~1.6275) and 1.0045 (95% CI: 0.9930~1.0160), respectively.

Conclusion: Exposure to PM_2.5, NO₂, PM₁₀, and SO₂ was significantly associated with influenza, which may be risk factors for influenza. The association of CO and O₃ with influenza needs further investigation.