1. Food Safety Monitoring and Evaluation Department, Guangxi Zhuang Autonomous Region Centre for Disease Control and Prevention (Guangxi CDC), Nanning, Guangxi Region, China
2. Department of Epidemiology, Faculty of Medicine, Prince of Songkla University, Hat Yai, Songkhla, Thailand
3. Infectious Department, The Fourth People’s Hospital of Nanning, Nanning, Guangxi Region, China