Affiliation: | Shandong University School of Public Health, Jinan, China (H.-L. Wen. L. Zhao, Y. Chi, D. Wang, Z. Wang, X.-J. Yu); ;Zibo Municipal Center for Disease Control and Prevention, Zibo, China (S. Zhai, F. Cui, L. Wang); ;Yiyuan County Center for Disease Control and Prevention, Yiyuan, China (Q. Wang, S. Zhang); ;University of Texas Medical Branch, Galveston, Texas, USA (Y. Liu, H. Yu, X.-J. Yu) |