Coggon Amelia, Lopes Sara, Simon Gaëlle, Arendsee Zebulun, Chen Kuan-Fu, Chiapponi Chiara, Essen Steve, Everett Helen, Hervé Séverine, Hufnagel David E, Mollett Benjamin, Moreno Ana, Pekosz Andrew, Richard Gautier, Rothman Richard E, Shaw-Saliba Kathryn, Van Reeth Kristien, Venkatesh Divya, Brown Ian H, Anderson Tavis K, Baker Amy L, Lewis Nicola S
Royal Veterinary College, London, United Kingdom.
Swine Virology Immunology Unit, Ploufragan-Plouzané-Niort Laboratory, French Agency for Food, Environmental and Occupational Health and Safety (ANSES), Ploufragan, France.
J Virol. 2025 Jul 22;99(7):e0030625. doi: 10.1128/jvi.00306-25. Epub 2025 Jun 4.
H1 and H3 influenza A viruses (IAVs) circulating in European pigs are markedly distinct from those circulating in other global swine populations. These viruses exhibit significant genetic diversity, further expanded by periodic interspecies transmission of IAVs from humans into pigs, followed by sustained circulation. Several zoonotic IAV infections in humans in Europe have been associated with the 1C lineage of H1 IAVs. Given the predominance of H1 detections in pigs and their zoonotic potential, we quantified antigenic evolution of H1 viruses in European pigs using ferret and pig models and assessed diversity relative to swine IAV vaccine strains. Ferret and swine antisera comparisons revealed no significant differences in antibody responses. Viruses of the 1A.3.3.2 clade exhibited reduced cross-reactivity to human seasonal vaccine strains from 2009. Viruses of the 1B.1.2.2 clade showed no cross-reactivity to the 1978 human seasonal influenza viruses nor to candidate vaccine viruses (CVVs). Clades 1C.2.1 and 1C.2.2 human variant strains had variable cross-reactivity to the tested 1C lineage CVVs, and 1C.2.4 and 1C.2.5 clade viruses exhibited rapid genetic diversification. Many viruses tested were antigenically distant from swine influenza vaccine-representative strains, highlighting the need for updated vaccine formulations. Importantly, age-stratified human serum panels revealed limited population cross-protection to tested viruses, particularly for antigenically heterogenous viruses. These findings quantify the genetic and antigenic diversity of co-circulating IAV lineages and identify specific groups of viruses that may represent a greater risk to animal and public health. These results can be used to inform future pre-pandemic preparedness efforts.IMPORTANCEOur data demonstrate the importance of matching swine influenza vaccine seed strains to contemporary circulating viruses and highlight how vaccine mismatch may drive additional antigenic evolution and demonstrate the need for constant monitoring and surveillance of swine viruses for the benefit of both animal and global health. These findings can be used to inform and prioritize future pre-pandemic preparedness efforts.
在欧洲猪群中传播的甲型H1和H3流感病毒（IAV）与全球其他猪群中传播的病毒明显不同。这些病毒表现出显著的遗传多样性，IAV从人类到猪的周期性种间传播以及随后的持续传播进一步扩大了这种多样性。欧洲人类中几起人畜共患IAV感染事件与H1 IAV的1C谱系有关。鉴于在猪中检测到的H1占主导地位及其人畜共患潜力，我们使用雪貂和猪模型对欧洲猪中H1病毒的抗原进化进行了量化，并评估了相对于猪IAV疫苗株的多样性。雪貂和猪抗血清比较显示抗体反应无显著差异。1A.3.3.2分支的病毒对2009年以来的人类季节性疫苗株的交叉反应性降低。1B.1.2.2分支的病毒对1978年人类季节性流感病毒和候选疫苗病毒（CVV）均无交叉反应性。1C.2.1和1C.2.2人类变异株对测试的1C谱系CVV的交叉反应性各不相同，1C.2.4和1C.2.5分支的病毒表现出快速的遗传多样化。许多测试病毒在抗原性上与猪流感疫苗代表性毒株相距甚远，凸显了更新疫苗配方的必要性。重要的是，按年龄分层的人类血清样本显示，对测试病毒的群体交叉保护有限，特别是对抗原性异质的病毒。这些发现量化了共同传播的IAV谱系的遗传和抗原多样性，并确定了可能对动物和公共卫生构成更大风险的特定病毒组。这些结果可用于为未来的大流行前防范工作提供信息。重要性我们的数据证明了使猪流感疫苗种子株与当代流行病毒相匹配的重要性，并强调了疫苗不匹配可能如何推动额外的抗原进化，还证明了为了动物和全球健康需要持续监测和监视猪病毒。这些发现可用于为未来的大流行前防范工作提供信息并确定优先事项。
