1. Institute of Public Health, Guangzhou Medical University & Guangzhou Center for Disease Control and Prevention, Guangzhou, Guangdong, China
2. Department of Intensive Care Unit, Shenzhen Second People’s Hospital, Shenzhen, Guangdong, China
3. Department of Environmental Health, School of Public Health, Southern Medical University, Guangzhou, Guangdong, China
4. Department of Laboratory Medicine, General Hospital of Southern Theatre Command of PLA, Guangzhou, Guangdong, China