Funding for this research was provided by:
National key research and development plan (2016YFC1200900, 2016YFC1202700)
China Mega-Project for Infectious Disease (2017ZX10302301-004, 2017ZX10104001)
Medical Research Key Project of Hebei Province (20180616)
Text and Data Mining valid from 2019-03-05
Received: 5 July 2018
Accepted: 13 February 2019
First Online: 5 March 2019
Ethics approval and consent to participate
: All aspects of the study were performed in accordance with national ethics regulations and approved by the Institutional Review Boards of National Institute for Viral Disease Control and Prevention, Center for Disease Control and Prevention of China, and written informed consents were obtained from the patients after informed them the use of data for analysis and using the results for improving patient care activities and without disclosing their names or identity.
: Not Applicable.
: All the authors approved the final manuscript and they have no conflict of interest to declare.
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