Glatman-Freedman Aharona, Pando Rakefet, Sefty Hanna, Omer Itay, Rosenberg Alina, Drori Yaron, Nemet Ital, Mendelson Ella, Keinan-Boker Lital, Mandelboim Michal, Israeli Influenza Surveillance Network Iisn For The
Israel Center for Disease Control, Israel Ministry of Health, Tel Hashomer, Ramat Gan 5265601, Israel.
School of Public Health, Tel Aviv University Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel.
Vaccines (Basel). 2020 Feb 9;8(1):78. doi: 10.3390/vaccines8010078.
Influenza A (H3N2) clade 3C.3a was the predominant influenza virus in Israel throughout the 2018-2019 season, constituting a drift from the influenza A (H3N2) vaccine. We estimated the end-of season vaccine effectiveness (VE) by age, among community patients with influenza-like illness (ILI), considering the hemagglutinin (HA) gene mutations and amino acid substitutions of influenza A (H3N2) viruses detected. Nose-throat samples were analyzed for the presence of influenza virus, type/subtype, and HA gene sequence. HA gene sequences and amino acid substitutions were compared to the influenza A/Singapore/INFIMH-16-0019/2016 (H3N2)-like 2018-2019 vaccine virus, and a phylogenetic tree was generated. Influenza VE against influenza A (H3N2) was estimated using the test-negative design. VE was estimated by age group and by 15 year moving age intervals. In total, 90% of the influenza A (H3N2) viruses belonged to the 3C.3a clade, constituting a unique situation in the northern hemisphere. Adjusted all-age influenza A (H3N2) VE was -3.5% (95% CI: -51.2 to 29.1). Although adjusted VEs were very low among infants, children, and young adults, a VE of 45% (95% CI: -19.2 to 74.6) was estimated among adults aged ≥45 years old. The higher VE point estimates among older adults may be related to previous exposure to similar influenza viruses.
甲型流感（H3N2）3C.3a分支是2018 - 2019季以色列的主要流感病毒，与甲型流感（H3N2）疫苗存在抗原漂移。我们在患有流感样疾病（ILI）的社区患者中，根据年龄估计了季末疫苗效力（VE），同时考虑了检测到的甲型流感（H3N2）病毒的血凝素（HA）基因突变和氨基酸替换情况。对鼻咽喉样本进行分析，以检测流感病毒的存在、类型/亚型以及HA基因序列。将HA基因序列和氨基酸替换与甲型流感/新加坡/INFIMH - 16 - 0019/2016（H3N2）样2018 - 2019疫苗病毒进行比较，并构建了系统发育树。使用检测阴性设计估计了针对甲型流感（H3N2）的流感疫苗效力。按年龄组和15年移动年龄间隔估计疫苗效力。总体而言，90%的甲型流感（H3N2）病毒属于3C.3a分支，这在北半球是一种独特情况。调整后的全年龄组甲型流感（H3N2）疫苗效力为 - 3.5%（95%置信区间： - 51.2至29.1）。尽管在婴儿、儿童和年轻人中调整后的疫苗效力非常低，但在≥45岁的成年人中估计疫苗效力为45%（95%置信区间： - 19.2至74.6）。老年人中较高的疫苗效力点估计可能与之前接触过类似流感病毒有关。
