1. Institute of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
2. Luang Prabang Agriculture and Forestry College, Lao People's Democratic Republic.
3. Zhejiang Entry-Exit Inspection and Quarantine Bureau of the People's Republic of China, Hangzhou, Zhejiang, China.
4. Microbiology Laboratory, Zhejiang Center for Disease Control and Prevention, Hangzhou, Zhejiang, China.