Funding for this research was provided by:
the Key Technology R&D Program (20170623032TC, 2015BAI07B02)
Text and Data Mining valid from 2018-05-22
Received: 3 February 2018
Accepted: 4 May 2018
First Online: 22 May 2018
Ethics approval and consent to participate
: The study was approved by the Ethical Committee of Changchun Infectious Disease Hospital (approval number 2017001). The need for informed consent was deemed unnecessary by the committee according to national regulations. No patient-identifying data were collected.
: The authors declare that they have no competing interests.
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