1. The National Clinical Key Department of Infectious Disease, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, China
2. National Health and Family Planning Commission of the People's Republic of China Key Laboratory for Medical Virology, Department of Viral Hemorrhagic Fever, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
3. Institute for Infectious Disease and Endemic Disease Control, Beijing Center for Disease Prevention and Control (CDC), Beijing 100013, China