Reply to: “Current smoking is not associated with COVID-19”
Janice M. Leung, Chen Xi Yang, Don D. Sin
Abstract
Like M. Rossato and co-workers, we too have been struck by the relative underrepresentation of current smokers in cohorts of coronavirus disease 2019 (COVID-19) patients, particularly in light of our recent findings that the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor angiotensin-converting enzyme II (ACE-2) is upregulated in the airway epithelium of this population [1]. China [2], Italy (as reported by M. Rossato and co-workers), and now New York City [3] have all reported current smoking rates below those of their respective general populations. The reason for this is a mystery. One possible explanation is misclassification of smoking status owing to under-reporting of smoking in these cohorts. Another is that smokers may be taking medications that may offer some protection against COVID-19 ( e.g. certain inhalers). Smoking and COPD are risk factors for severe COVID-19 <https://bit.ly/2KJxAbp>