1. 1Guangxi Zhuang Autonomous Region Center for Disease Prevention and Control, Guangxi Key Laboratory for the Prevention and Control of Viral Hepatitis, Nanning, Guangxi 530028, PR China
2. 2School of Preclinical Medicine, Guangxi Medical University, UCL Medical School, 22 ShuangYong Road Nanning, Guangxi 530021, PR China
3. 3Division of Medicine, UCL Medical School, London, UK
4. 4Guangdong Provincial Institute of Public Health, Guangdong Provincial Center for Disease Control and Prevention, Guangzhou 511430, PR China