Analysis on pathogenic surveillance of influenza in Weifang city,Shandong province from 2017 to 2023
Objective To analyze the etiological and incidence trend of influenza in Weifang city from 2017 to 2023,so as to provide reference for influenza prevention and control.Methods The data on the pathogenetic surveillance of influen-za-like illness(ILI)cases in national sentinel hospitals and the outbreak epidemic in Weifang city,Shandong province were collected from 2017 to 2023,and the data were analyzed by SPSS 20.0 statistical software.Results A total of 4 241 throat swab samples were collected from sentinel hospitals from 2017 to 2023,and 581 positive samples were detected,and positive rate of the influenza virus nucleic acid was 13.70％.The proportion of H1N1 influenza virus was the highest(33.56％),followed by Victoria B influenza virus(27.02％).Except for the 2020 to 2021 period when no influenza virus was detected,there was a trend of common or alternating outbreaks of different subtypes of strains in other years.The dominant strains in 2017 to 2018 were H1N1 virus and Yamagata virus,the dominant strains in 2018 to 2019 were H1N1 virus and H3N2 virus,the dominant strain in 2019-2020 was the H3N2 virus,the dominant strain in 2021 to 2022 was Vic-toria B virus(100％),the dominant strains in 2022 to 2023 were H3N2 virus and H1N1 virus.There was a statistically significant difference in the positive rate of influenza virus nucleic acid detection in different seasons(x2=189.893,P＜0.001),mainly in winter and spring.There was no statistically significant difference in positive detection rates between genders(x2=2.214,P＞0.05),and there was a statistically signifi-cant difference in the positive rate of influenza virus nucleic acid detection among different age groups(x2=205.666,P＜0.001),the highest positive rate of nucleic acid testing was in the 15-24 age group(23.73％).A total of 54 ILI outbreaks were reported from 2017 to 2023,they were mainly occurred in primary schools(48.15％)and secondary schools(18.52％),mainly caused by the B Yamagata virus,followed by the A H3N2 virus and the B Victoria virus.Conclusion The influenza epidemic in Weifang city from 2017 to 2023 showed a trend of alternating outbreaks of different dominant strains,attention should be paid to gathering places such as schools,and continuous monitoring of ILI should be carried out.
NETL
NSTL
万方数据
