Funding for this research was provided by:
National Basic Research Program of China (2012CB955504)
Medical Research Program of Zhejiang Province (2015RCA005)
Received: 18 August 2017
Accepted: 19 February 2018
First Online: 23 February 2018
Ethics approval and consent to participate
: Experimental research reported in this study has been performed with the approval of the ethics committee of Zhejiang Provincial Centre for Disease Control and Prevention (Zhejiang CDC). Human research was carried out in compliance with the Helsinki Declaration. Written consents were obtained from participants (> 16 years old) or a parent or guardian on behalf of any participants under the age of 16.
: Not applicable.
: The authors declare that they have no competing interests.
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