Epidemic characteristics and influencing factors of influenza outbreaks in Xinwu District of Wuxi in 2017-2019 / 公共卫生与预防医学

ABSTRACT

Objective To analyze the epidemic characteristics and influencing factors of influenza outbreaks in Xinwu District of Wuxi City from 2017 to 2019, and to provide a basis for the prevention and control of influenza outbreaks in schools. Methods The 2017-2019 influenza data was retrieved from the China Influenza Surveillance Information System and the Public Health Emergency Management System. A descriptive epidemiology method was used to analyze the characteristics of the influenza outbreaks. The related factors on the epidemic intensity and duration were analyzed. Results From 2017 to 2019, a total of 26 influenza outbreaks occurred in Xinwu District, with a cumulative total of 927 cases and an average prevalence rate of 1.74%. The outbreaks mainly occurred between November and April of the following year, accounting for 100%. The outbreaks all occurred in schools, with primary schools accounting for 88.46% (23/26) and kindergartens accounting for 11.54% (3/26) of the total. The main influenza viruses that caused influenza outbreaks were B/Victoria and B/Yamagata, which accounted for 65.60% (164/250) and 16.40% (41/250), respectively, followed by influenza A/H3N2, which accounted for 16% (40/250). The epidemic intensity was related to the number of students (P < 0.05), and the duration of the epidemic was related to the type of schools and the reporting time of the epidemic (P < 0.05). Conclusion The outbreaks of influenza had obvious seasonality, and occurred mainly in schools. Improving the timeliness of epidemic reporting and taking timely control measures are the key to controlling influenza outbreaks in schools.