Jianxing Yu1, Shengjie Lai1, Xin Wang2, Qiaohong Liao1, Luzhao Feng1, Lu Ran1, Wenbo Xu3, Yanzi Qiu4, Zike Zhang5, Mengfeng Li6, Jianguo Wu4, Wei Liu7, Zhenghong Yuan8, Yu Chen5, Shiwen Zhao9, Xinhua Wang10, Zhuo Zhao11, Hongjie Yu1, Huaiqi Jing2, Zhongjie Li1, Weizhong Yang12. 1. Division of Infectious Disease, Key Laboratory of Surveillance and Early-warning on Infectious Disease, Beijing 102206, China. 2. National Institute for Communicable Diseases Control and Prevention, Beijing 102206, China. 3. National Institute for Viral Diseases Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China. 4. State Key Laboratory of Virology, College of Life Sciences, Wuhan University. 5. State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, First Affiliated Hospital, School of Medicine, Zhejiang University. 6. Key Laboratory of Tropical Disease Control, Ministry of Education, Sun Yat-Sen University. 7. State Key Laboratory of Pathogen and Biosecurity, Institute of Microbiology and Epidemiology, Military Medical Science Academy. 8. Shanghai Public Health Clinical Center. 9. Yunnan Provincial Center for Disease Control and Prevention. 10. Gansu Provincial Center for Disease Control and Prevention. 11. Liaoning Provincial Center for Disease Control and Prevention. 12. Chinese Center for Disease Control and Prevention; Email: yangwz@chinacdc.cn.
Abstract
OBJECTIVE: To investigate the epidemiology characteristics of norovirus among diarrheal outpatients in China. METHODS: Diarrhea cases were monitored at emergency/outpatient departments at 173 hospitals in 27 provinces of China, with clinical and epidemiological data, and fecal specimens collected and sent to 58 network-laboratories to detect norovirus by RT-PCR method, and to analyze the positive rate of norovirus in various regions, population and time during 2009-2013. RESULTS: 11.6% of the 34 031 diarrheal cases under surveillance were found with norovirus. Age group of 6-23 month-old children and that of people over 45 years old were found with the highest positive percentage, 13.7% and 12.4% respectively. Positive percentage of norovirus peaks in autumn and winter in a year; it peaks in mid-temperate zones (10.7%) and warm-temperate zones (11.6%) in winter. It peaks in sub-tropical zones in autumn (14.3%). The most prevalent genogroups detected were norovirus G II, accounting for 89.9% of identified strains. CONCLUSION: Norovirus affects all ages and was most prevalent in children and the elderly among diarrhea outpatients. Norovirus' positive percentage showed strong seasonal pattern, and peaks at different times of a year in different climate zones of China. Since no effective preventive measures existed, further study on norovirus epidemiology and intervention strategies should be conducted in future.
OBJECTIVE: To investigate the epidemiology characteristics of norovirus among diarrheal outpatients in China. METHODS:Diarrhea cases were monitored at emergency/outpatient departments at 173 hospitals in 27 provinces of China, with clinical and epidemiological data, and fecal specimens collected and sent to 58 network-laboratories to detect norovirus by RT-PCR method, and to analyze the positive rate of norovirus in various regions, population and time during 2009-2013. RESULTS: 11.6% of the 34 031 diarrheal cases under surveillance were found with norovirus. Age group of 6-23 month-old children and that of people over 45 years old were found with the highest positive percentage, 13.7% and 12.4% respectively. Positive percentage of norovirus peaks in autumn and winter in a year; it peaks in mid-temperate zones (10.7%) and warm-temperate zones (11.6%) in winter. It peaks in sub-tropical zones in autumn (14.3%). The most prevalent genogroups detected were norovirus G II, accounting for 89.9% of identified strains. CONCLUSION: Norovirus affects all ages and was most prevalent in children and the elderly among diarrhea outpatients. Norovirus' positive percentage showed strong seasonal pattern, and peaks at different times of a year in different climate zones of China. Since no effective preventive measures existed, further study on norovirus epidemiology and intervention strategies should be conducted in future.