Funding for this research was provided by:
National Natural Science Foundation of China (81672005, 81001271, 81721091)
Fundamental Research Funds for the Central Universities (2017FZA7004)
Mega-Project of National Science and Technology for the 12th Five-Year Plan of China (2018ZX10715-014-002, 2014ZX10004008, 2013ZX10004901, 2013ZX10004904 and 2011ZX10004-901)
Key Joint Project for Data Center of the National Natural Science Foundation of China (U1611264)
National Institute of Allergy and Infectious Diseases, National Institutes of Health, U.S. Department of Health and Human Services, USA (HHSN272201400006C)
Received: 21 February 2019
Accepted: 11 June 2019
First Online: 29 July 2019
Ethics approval and consent to participate
: This study was approved by the research ethics board at the center of 5 alliance hospitals, the First Affiliated Hospital, School of Medicine, Zhejiang University. It was retrospectively non-invasive study, and the data were analyzed anonymously; therefore, the verbally informed consent from patients, parents or legal guardians of children under 18 years old was obtained.
: Not applicable.
: The authors declare that they have no competing interests.