1. Institute of EcoHealth, School of Public Health, Cheeloo College of Medicine Shandong University Jinan Shandong P. R. China
2. State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and Epidemiology Beijing P. R. China
3. Beijing Center for Disease Prevention and Control Beijing Academy for Preventive Medicine Beijing P. R. China
4. Research Unit of Discovery and Tracing of Natural Focus Diseases Chinese Academy of Medical Sciences Beijing P. R. China