1. State Key Laboratory for Infectious Disease Prevention and Control, Department of Zoonoses, Institute for Infectious Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Liuzi 5, 102206 Beijing, PR China
2. Medical Institute of Nanjing Army, Nanjing, PR China
3. State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, 430070 Wuhan, PR China
4. Department of Pathology, University of Georgia, Athens, GA 30602, USA