1. Shanghai Institute for Emerging and Re-emerging Infectious Diseases, Shanghai Public Health Clinical Center, Shanghai 201508, PR China
2. State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing 102206, PR China
3. School of Biology and Food Sciences, Shangqiu Normal University, Shangqiu, Henan 476000, PR China
4. Shaanxi Institute of Zoology, Xi'an 710032, PR China