1. Xuzhou Center for Disease Control and Prevention, Xuzhou, People’s Republic of China
2. Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, People’s Republic of China
3. Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
4. College of Public Health, University of Arkansas for Medical Sciences, Little Rock, AR, USA
5. School of Public Health, Rutgers University, New Brunswick, NJ, USA