Funding for this research was provided by:
the National Key Research and Development Program (2016YFC1200902)
the Key Technologies R&D Program of the National Ministry of Science (2018ZX10713002)
Received: 9 August 2019
Accepted: 13 February 2020
First Online: 13 March 2020
Ethics approval and consent to participate
: The experiment was approved by the animal experimental ethics committee of the National Institute for Viral Disease Control and Prevention, China CDC (No 20180522027).
: Not applicable.
: The authors declare that they have no competing interests.