Broberg Eeva K, Vukovikj Maja, Svartström Olov, Hasibra Iris, Riess Maximilian, Melidou Angeliki
European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden.
World Health Organization (WHO) Regional Office for Europe, Copenhagen, Denmark.
Euro Surveill. 2024 Dec;29(50). doi: 10.2807/1560-7917.ES.2024.29.50.2400395.
BackgroundDuring the 2023/24 influenza season in the European Union/European Economic Area (EU/EEA), influenza viruses A(H1N1)pdm09, A(H3N2) and B/Victoria viruses were co-circulating.AimWe aimed to describe the circulating influenza viruses by (sub)type, genetic clade, antigenic group and antiviral susceptibility in that season in the EU/EEA.MethodsWe collected surveillance data from EU/EEA countries through weekly submissions to The European Surveillance System (TESSy). Data were submitted in strain-based format for weeks 40/2023 to 9/2024.ResultsTwenty-nine EU/EEA countries reported 154,718 influenza virus detections (primary care sentinel and non-sentinel combined), of which 97% (150,692) were type A and 3% (4,026) were type B. Of the subtyped influenza A viruses, 30,463 (75%) were influenza A(H1)pdm09 and 10,174 (25%) were influenza A(H3). For 809 (20%) of the type B viruses, the lineage was determined; all were B/Victoria/2/87 lineage, and none were B/Yamagata/16/88 lineage. Genetic diversification of seasonal influenza viruses continued, and clade 5a.2a of A(H1N1)pdm09, 2a.3a.1 of A(H3N2) and V1A.3a.2 of B/Victoria-lineage viruses dominated. Of the A(H3N2) 2a.3a.1 viruses, 23% were antigenically distinct from the 2023/24 vaccine virus.ConclusionThe 2023/24 influenza season was characterised by co-circulation of different influenza (sub)types, antigenically similar to the components recommended for the 2023/24 northern hemisphere vaccine, A/Victoria/4897/2022 (egg-based) and A/Wisconsin/67/2022 (cell culture- or recombinant-based). However, genetic diversification of the viruses continued. The World Health Organization's vaccine recommendations for the northern hemisphere 2024/25 season were updated to include a new A(H3N2) component, while maintaining the current A(H1N1)pdm09 and B/Victoria components.
背景
在欧盟/欧洲经济区（EU/EEA）2023/24流感季期间，甲型（H1N1）pdm09流感病毒、甲型（H3N2）流感病毒和乙型维多利亚系流感病毒共同流行。
目的
我们旨在描述该流感季在欧盟/欧洲经济区流行的流感病毒的（亚）型、基因分支、抗原组和抗病毒敏感性。
方法
我们通过每周向欧洲监测系统（TESSy）提交数据，收集了欧盟/欧洲经济区国家的监测数据。数据以基于毒株的格式提交，涵盖2023年第40周（即2023年10月5日 - 10月11日）至2024年第9周（即2024年2月23日 - 3月1日）。
结果
29个欧盟/欧洲经济区国家报告了154,718例流感病毒检测结果（包括初级保健哨点和非哨点检测结果），其中97%（150,692例）为甲型，3%（4,026例）为乙型。在已分型的甲型流感病毒中，30,463例（75%）为甲型（H1）pdm09流感病毒，10,174例（25%）为甲型（H3）流感病毒。对于809例（20%）乙型流感病毒，确定了其谱系；均为B/维多利亚/2/87谱系，无B/山形/16/88谱系。季节性流感病毒的基因多样性持续存在，甲型（H1N1）pdm09的5a.2a分支、甲型（H3N2）的2a.3a.1分支和乙型维多利亚系病毒的V1A.3a.2分支占主导地位。在甲型（H3N2）2a.3a.1病毒中，23%在抗原性上与2023/24疫苗病毒不同。
结论
2023/24流感季的特点是不同流感（亚）型共同流行，在抗原性上与2023/24北半球疫苗推荐成分相似，即A/维多利亚/4897/2022（鸡胚培养）和A/威斯康星/67/2022（细胞培养或重组）。然而，病毒的基因多样性仍在持续。世界卫生组织对2024/25北半球流感季的疫苗建议进行了更新，纳入了一种新的甲型（H3N）成分，同时保留了现有的甲型（H1N1）pdm09和乙型维多利亚成分。
