Funding for this research was provided by:
Science and Technology Commission of Shanghai Municipality (20JC1410200)
Received: 10 March 2020
Accepted: 8 October 2020
First Online: 20 October 2020
Ethics approval and consent to participate
: This study was reviewed and approved by Shanghai Municipal Center for Disease Control and Prevention Ethics Review Committee, which waived the written informed consent for emerging infectious diseases. The data were analyzed anonymously.
: Not applicable.
: The authors declare that they have no competing interests.