Funding for this research was provided by:
Chinese Center for Disease Control and Prevention (131031001000150001)
Major Science and Technology Special Project (2017ZX10105015)
Text and Data Mining valid from 2019-10-03
Received: 13 March 2019
Accepted: 22 August 2019
First Online: 3 October 2019
Ethics approval and consent to participate
: Not applicable.
: All authors of this manuscript declare that we have approved the submission and publication of this manuscript.