tetano
Editor, Senior Moderator
Virol J
. 2025 Nov 4;22(1):359.
doi: 10.1186/s12985-025-02974-6. Genetic characteristics of influenza A/H3N2 virus in Jiaxing, China (2019-2024)
Yin Song[SUP] #[/SUP][SUP] 1 [/SUP], Xue Zhang[SUP] #[/SUP][SUP] 2 [/SUP], Jimei Ji[SUP] #[/SUP][SUP] 3 [/SUP], Lina Li[SUP] 3 [/SUP], Yamei Zhou[SUP] 3 [/SUP], Ping Li[SUP] 3 [/SUP], Ganglin Ren[SUP] 3 [/SUP], Shencong Lv[SUP] 3 [/SUP], Xiaofei Zhang[SUP] 3 [/SUP], Yong Yan[SUP] 4 [/SUP], Guoying Zhu[SUP] 5 [/SUP]
Affiliations
The rapid evolution of influenza A/H3N2 virus underscores the imperative for ongoing surveillance. In this study, we analyzed 7,872 respiratory samples collected from patients with influenza-like symptoms in Jiaxing, China, between 2019 and 2024, selecting 117 influenza A/H3N2 strains for whole-genome sequencing. Between 2019 and 2024, the influenza A/H3N2 virus in Jiaxing experienced six epidemic peaks, evolving from clades 3 C.2a1b.1a/1b, 3 C.2a1b.2, and 3 C.2b1b.2a.2a.3/3b to clade 3 C.2a1b.2a.2a.3a.1. Compared with the 2019-2021 period, influenza A/H3N2 viruses circulating in Jiaxing during 2022-2024 demonstrated a longer evolutionary distance and increased hemagglutination titers. Additionally, seven novel amino acid substitutions (H156S, Y159N, T160I, S186D, D190N, I192F, N96S) were identified in HA antigenic epitopes of circulating influenza A/H3N2 viruses during 2023-2024. Notably, based on predicted vaccine effectiveness, the 2023-2024 influenza vaccine retained strong protective efficacy. In conclusion, this study characterizes the evolutionary features of influenza A/H3N2 virus in Jiaxing during 2019-2024. These results enhance our understanding of the natural evolution of influenza virus and the emergence of new variants, providing critical insights into influenza vaccine effectiveness.
Keywords: Hemagglutination, amino acid mutation, whole-genome sequencing; Influenza A/H3N2 virus; Vaccine efficacy.
. 2025 Nov 4;22(1):359.
doi: 10.1186/s12985-025-02974-6. Genetic characteristics of influenza A/H3N2 virus in Jiaxing, China (2019-2024)
Yin Song[SUP] #[/SUP][SUP] 1 [/SUP], Xue Zhang[SUP] #[/SUP][SUP] 2 [/SUP], Jimei Ji[SUP] #[/SUP][SUP] 3 [/SUP], Lina Li[SUP] 3 [/SUP], Yamei Zhou[SUP] 3 [/SUP], Ping Li[SUP] 3 [/SUP], Ganglin Ren[SUP] 3 [/SUP], Shencong Lv[SUP] 3 [/SUP], Xiaofei Zhang[SUP] 3 [/SUP], Yong Yan[SUP] 4 [/SUP], Guoying Zhu[SUP] 5 [/SUP]
Affiliations
- PMID: 41188942
- DOI: 10.1186/s12985-025-02974-6
The rapid evolution of influenza A/H3N2 virus underscores the imperative for ongoing surveillance. In this study, we analyzed 7,872 respiratory samples collected from patients with influenza-like symptoms in Jiaxing, China, between 2019 and 2024, selecting 117 influenza A/H3N2 strains for whole-genome sequencing. Between 2019 and 2024, the influenza A/H3N2 virus in Jiaxing experienced six epidemic peaks, evolving from clades 3 C.2a1b.1a/1b, 3 C.2a1b.2, and 3 C.2b1b.2a.2a.3/3b to clade 3 C.2a1b.2a.2a.3a.1. Compared with the 2019-2021 period, influenza A/H3N2 viruses circulating in Jiaxing during 2022-2024 demonstrated a longer evolutionary distance and increased hemagglutination titers. Additionally, seven novel amino acid substitutions (H156S, Y159N, T160I, S186D, D190N, I192F, N96S) were identified in HA antigenic epitopes of circulating influenza A/H3N2 viruses during 2023-2024. Notably, based on predicted vaccine effectiveness, the 2023-2024 influenza vaccine retained strong protective efficacy. In conclusion, this study characterizes the evolutionary features of influenza A/H3N2 virus in Jiaxing during 2019-2024. These results enhance our understanding of the natural evolution of influenza virus and the emergence of new variants, providing critical insights into influenza vaccine effectiveness.
Keywords: Hemagglutination, amino acid mutation, whole-genome sequencing; Influenza A/H3N2 virus; Vaccine efficacy.