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Article History

Received: 20 June 2021

Accepted: 11 September 2021

First Online: 23 September 2021

Declarations

:

: We have verified consent from subjects participating in the study was received prior to conducting the study and provided written assurance that the study has been reviewed and approved by an accredited committee. The study was approved by the Committee on the Ethics of Tianjin Centers for Disease Control and Prevention (permit number: TJCDC0111).

: Not applicable.

: The authors declare no competing interests.