Funding for this research was provided by:
Infectious Diseases Control Project from Ministry of Health of China (2016zx10004207-004)
Received: 24 February 2017
Accepted: 21 December 2017
First Online: 1 February 2018
Ethics approval and consent to participate
: The study protocol was approved by the Tongji Hospital ethics committee for research in health. Informed written consent was obtained from the parents or legal guardian of the patient before inclusion in the study.
: Not applicable.
: The authors declare that they have no competing interests.
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