Received: 28 July 2021
Accepted: 29 November 2021
First Online: 9 December 2021
: The current study was approved by the ethics committees of Beijing Institute of Microbiology and Epidemiology in accordance with the medical research regulations of China. The procedures of this study complied with the provisions of the Declaration of Helsinki regarding research on Human participants.
: Not applicable.
: All authors declare no competing interests.