Abstract:Objective To analyze the epidemiological characteristics of norovirus outbreaks in Haidian District, Beijing, and to provide a reference for epidemic prevention and control. Methods Descriptive epidemiological methods were used to organize and statistically analyze the norovirus outbreak data reported from 2016 to 2022. Results A total of 26 outbreaks of norovirus were reported in Haidian District, with a total of 1595 cases and an attack rate M (QR) of 8.23 (16.33)%. There were 24 cases of norovirus type GII (92.31%), 1 case of type GI (3.85%), and 1 case of mixed infection of virus type GI/GII (3.85%). The highest number of reported outbreaks occurred in March and April, with 17 cases, accounting for 65.38%. The highest number of reported cases was in November and December, with 785 cases, accounting for 44.92%. The case age M (QR) was 18 (14) years old. The detection rate of positive samples in different age groups had statistical significance( c2 =12.021, P=0.007). The 26 outbreaks were mainly distributed in collective units such as schools, preschool institutions, and enterprises and institutions. There were a total of 11 outbreaks related to foodborne transmission, with 923 cases, accounting for 57.87%. Diarrhea was positively correlated with the age of the cases (rs=0.572, P<0.001), while vomiting was negatively correlated with the age of the cases (rs=-0187, P<0.001). The time interval between the onset of acute gastroenteritis symptoms in the first case and the reporting of the epidemic was positively correlated with the duration of the epidemic (rs=0.586, P=0.002). Conclusion It is necessary to strengthen the prevention and control of norovirus in schools (primary and secondary schools and colleges), strictly implement health monitoring and regular screening for kitchen workers, carry out publicity and education, detect cases as early as possible, report the epidemic in a timely manner, and effectively reduce the scale of the epidemic and prevent its spread.