Funding for this research was provided by:
Text and Data Mining valid from 2018-11-06
Received: 7 March 2018
Accepted: 24 October 2018
First Online: 6 November 2018
Ethics approval and consent to participate
: The study was approved by the Institutional Review Board of NCAIDS, China CDC (Approval X150129351). Study data were de-identified prior to analysis. All study participants provided signed informed consent.
: Not applicable.
: The authors declare that they have no competing interests.
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