1. Department of Epidemiology, College of Preventive MedicineThird Military Medical University 400038 Chongqing China
2. Department of EpidemiologyResearch Institute for Medicine of Nanjing Command 210002 Nanjing China
3. Jiangsu Institute of Parasitic Diseases 214064 Wuxi Jiangsu Province P.R. China
4. Stony Brook University 11794 Stony Brook USA
5. Department of Pathogen Biology & Microbiology and Department of General Intensive Care Unit of the Second Affiliated Hospital, Zhejiang University School of Medicine 310058 Hangzhou Zhejiang China