关键词: 流行性感冒, 流感病毒, 暴发, 流行病学特征, 病原学, 贵港市

Abstract: Objective To analyze the epidemic characteristics and the handling of the outbreak of influenza in Guigang City from 2013 to 2022,so as to provide a reference for formulating effective prevention and control strategies and measures. Methods The "Monitoring Report Management System" and "China Influenza Monitoring Information System" modules in the China Disease Control and Prevention Information System were used to collect influenza case monitoring reports and outbreak related information data in Guigang City from 2013 to 2022,and the data were analyzed. Results A total of 18 835 influenza cases were reported in Guigang City from 2013 to 2022,with 4 deaths,and the annual average incidence rate was 43.59/100 000. Cases had been reported in all age groups,with the majority of cases occurring in the 0-<6 age group（9 810 cases） and the 6-<11 age group（3 853 cases）,accounting for 72.54% of the total number of cases（13 663/18 835）. There was a statistically significant difference in influenza incidence rate among different counties（cities and districts）（χ²=17 767.888,P<0.05）. The peak of incidence presented alternating single and double peaks,mainly concentrated from December to January and April to July of the following year. From 2013 to 2022,a total of 11 361 throat swabs of influenza like cases were collected from sentinel hospitals in Guigang City,and 1 724 influenza virus nucleic acid positive samples were detected. The total nucleic acid positive rate was 15.17%,including 1 060 cases of influenza A,accounting for 61.48%,and 664 cases of influenza B,accounting for 38.52%. From 2013 to 2022,a total of 25 outbreaks were reported,including 13 cases of influenza B and 12 cases of influenza A. The average number of cases involved in each event was 56.04. The average reporting date from the onset date of the first case to the outbreak of the epidemic was 5.76 days,with a date interval concentrated within 7 days and a maximum of 9 days,and the duration of the outbreak was concentrated in 8（7,14）days. The discovery time of the outbreak was positively correlated with the duration of the epidemic（r=0.387,P<0.05）. Out of the 25 outbreaks,22 occurred in schools. Conclusion From 2013 to 2022,the influenza epidemic period in Guigang City was mainly in winter and spring,with the peak incidence mostly occurring from November to December and January of the following year. In 2022,there was a summer epidemic peak,and different influenza subtypes alternated in different influenza monitoring years. Therefore,further monitoring and early warning of influenza should be strengthened. Infants and children are high-risk groups for influenza,and schools are high risk areas for influenza,especially outbreaks. For high-risk groups,it is necessary to strengthen the promotion and mobilization of influenza vaccine vaccination to increase the vaccination rate and strictly prevent the large-scale spread of the influenza epidemic.

Key words: Influenza, Influenza virus, Outbreak, Epidemiological characteristics, Etiology, Guigang City