Two (1.4%) patients had COPD in our report; the percentage is similar as that reported by Guan et al4 (12/1099, 1.1%). In addition, only 9 (6.4%) patients had a history of smoking, and 7 of them were past smokers. It was reported that the prevalence of COPD in adults ≥40 years old was 13.7%,22 and 27.3% of adults in China were current cigarette smokers (data in 2018).35 The relationship between smoking and coronavirus infection is not clear, and the exact underlying causes of the lower incidence of COVID-19 in current smokers are still unknown. Previous study demonstrated that CoV was not frequently detected by RT-PCR in the exacerba-tion of COPD, as compared to other respiratory viruses such as RV, EnV, RSV, and IfV, indicating that coronavirus plays a minor role in the acute exacerbation of COPD.23 Although our study found that COPD and smoking populations were less likely to be infected with SARS-CoV-2, but the outcome of SARS-CoV-2 infection in smokers may be more severe.
https://onlinelibrary.wiley.com/doi/epdf/10.1111/all.14238