Liu, Ran
Cai, Jianning
Guo, Weiheng
Guo, Wei
Wang, Wenjuan
Yan, Lina
Ma, Ning
Zhang, Xiaolin
Zhang, Shiyong
Article History
Received: 24 June 2021
Accepted: 3 September 2021
First Online: 22 September 2021
Declarations
:
: This study has been approved by the ethics committee of the Shijiazhuang Center for Disease Control (202006). The data of this study do not involve any personal information. Private information has been erased before research.
: Not applicable.
: The authors declare no competing interests.