School of Medicine;
Xi'an Jiao-Tong University;
Zhu-Que Street 205;
Xi'an 710061;
Shaanxi;
China;
National Institute for Viral Disease Control and Prevention;
Chinese Center for Disease Control and Prevention;
Hngxin Rd. 100;
Beijing 100052;
China;
National Laboratory of Medical Molecular Biology;
Institute of Basic Medical Science;
Chinese Academy of Medical Sciences and Peking Union Medical College;
Dong Dan San Tiao 5;
Beijing 100005;
China;