Acknowledgements
We thank Dr. Danielle Anderson of Duke-NUS Medical School for critical review of this report. We thank National Virus Resource Center (NCRC) in Wuhan Institute of Virology.

Disclosure statement
No potential conflict of interest was reported by the author(s).

ORCID
Zheng-Li Shi http://orcid.org/0000-0001-8089-163X
Peng Zhou http://orcid.org/0000-0001-9863-4201