1 College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou 450046, China; CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
2 CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
3 CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; Chinese Center for Disease Control and Prevention (China CDC), Beijing 102206, China. Electronic address: gaof@im.ac.cn.