1
Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Jiangsu Province, Nanjing, Jiangsu Province, PR China
2
University of Georgia, School of Public Health, Department of Epidemiology and Biostatistics, Athens, Georgia, United States
3
Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana
4
Department of Epidemiology, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, PR China
5
Stanford University, School of Medicine, Division of Infectious Diseases and Geographic Medicine, Stanford, California, United States
✉Corresponding author: Professor Wei Lu, Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Jiangsu Province, Nanjing, Jiangsu Province, PR China. Tel: +86 25 83759455; Fax: +86 25 83759905; Email weiluxx@sina.cn
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