Liu, Jundi
Chen, Yan
Hu, Peipei
Gan, Lin
Tan, Qimin
Huang, Xinqiao
Ma, Zhanzhong
Lin, Cuiji
Wu, Dawei
Zhu, Xun
Zhang, Dingmei
Funding for this research was provided by:
the National Mega Project on Major Infectious Disease Prevention (2017ZX10103011)
the Guangdong Provincial Science and Technology Program (2017A070713013)
Article History
Received: 18 January 2021
Accepted: 3 April 2021
First Online: 23 April 2021
Declarations
:
: In accordance with the guidelines for the protection of human subjects, ethics approval was obtained from the Institutional Review Board of the School of Public Health at Sun Yat-sen University (2019019). After learning the research subject matter and being promised to keep their personal information confidential, written informed consent was obtained from all caregivers and a parent or guardian for participants aged five years old or younger. Each participant could withdraw any time if they wanted to.
: Not applicable.
: The authors declare that they have no competing interests.