Comparison of clinical and immunological profiles in coronavirus disease 2019 and influenza patients: a case control study

The pandemic caused by the SARS-CoV-2 coronavirus is still looming worldwide, and the pandemic has challenged health care delivery and health care systems internationally. [1] The epidemic of seasonal influenza would occur in the winter months. Since coronavirus disease 2019 (COVID-19) and influenza share many clinical symptoms, [2] it is difficult to distinguish these two respiratory infections in the early stage. [3] Although nucleic acid testing was the gold standard to identify different virus infected diseases, false-negative nucleic acid results were reported frequently in COVID-19, [4] and its diagnostic sensitivity is less optimal. Therefore, the aim of our study is to explore and compare the clinical characteristics of COVID-19 and influenza, which could deepen the understanding of these two diseases and provide some guidance for clinicians to make a differential diagnosis.