Received: 15 June 2020
Accepted: 1 July 2020
First Online: 11 July 2020
Ethics approval and consent to participate
: The Clinical Research Ethics Commissions of Taikangtongji Hospital approved the study and granted a waiver for the need to obtain written informed consent from the study participants as COVID-19 is an emerging infectious disease.
: Not applicable.
: All authors declare no competing interests.