Funding for this research was provided by:
Anhui provincial Program of Prevent medicine & Public Health (2017jk002)
the NSFC (81773493, 81273137)
the State Key Laboratory of Pathogen and Biosecurity (AMMS), the National Key S&T Special Projects on Major Infectious Diseases (2018ZX10721102, 2018ZX10732101-001-003)
National Grand Program on Key Infectious Disease Control (2017ZX10201101)
the Special Key Project of Biosafety Technologies (2017YFC1200800)
Received: 21 November 2019
Accepted: 13 January 2020
First Online: 3 February 2020
Ethics approval and consent to participate
: This study was reviewed and approved by the ethics committees of the Beijing Institute of Microbiology and Epidemiology and the Anhui Center for Disease Prevention and Control. All participants signed written informed consent prior to sample donations.
: Not applicable.
: The authors declare that they have no competing interests.