Liao, Bin
Zhang, Xiao-Wen
Wang, Jing-Ying
Liu, Jun
Liang, Jun
He, Wen-Jie
Hong, Biao
Li, Yi
Article History
Received: 8 July 2019
Accepted: 22 November 2019
First Online: 10 December 2019
Ethics approval and consent to participate
: This study reviewed and approved by Ethics Committee of Kunming Center for Disease Control and Prevention. The informed consent obtained from participants was verbal.
: Not applicable.
: The authors declare that they have no competing interests.