Virus and Prion Research Unit, National Animal Disease Center, Agricultural Research Service, USDA, Ames, IA, United States.
Virus and Prion Research Unit, National Animal Disease Center, Agricultural Research Service, USDA, Ames, IA, United States.
Vaccine. 2019 Mar 7;37(11):1533-1539. doi: 10.1016/j.vaccine.2018.12.071. Epub 2019 Feb 2.
Influenza A virus in swine (IAV-S) is an important pathogen in pigs in the United States, in addition to posing a potential risk to humans through zoonotic events. Intervention strategies continue to be explored to better control virus circulation. Improved surveillance efforts has led to significantly increased sequence data available on circulating strains, vastly improving our understanding of the genetic and antigenic diversity of IAV-S. IAV-S in North America is characterized by repeated spillover events of human viruses into pigs followed by genetic and antigenic diversification. An important gap that needs to be addressed is our understanding of the role that various vaccine platforms have on efficacy against antigenically heterologous challenge. Currently licensed vaccines often update their components to adapt to a dynamic antigenic landscape and newly developed technologies continue to be approved. Hence, it remains critical to test the performance of vaccines against challenge with antigenically distinct viruses. We tested the level of protection conferred by an alphavirus-vectored hemagglutinin (HA) subunit vaccine, delivered as a monovalent or bivalent formulation, against challenge with IAV-S. Monovalent alphavirus-vectored HA vaccines provided efficient protection against challenge with viruses with matched and mismatched HA, although in one mismatched HA challenge group there was a trend for reduced protection. A bivalent vaccine, in which two HA's were simultaneously delivered, was effective in producing antibody response against both antigens and provided protection against challenge. The alphavirus platform is a promising new technology available to swine producers to help reduce the burden of disease caused by IAV-S.
猪流感病毒（IAV-S）是美国猪群中的一种重要病原体，它通过人畜共患病事件对人类构成潜在风险。目前仍在探索干预策略，以更好地控制病毒传播。改进监测工作，使更多的循环毒株序列数据得以提供，这大大提高了我们对 IAV-S 的遗传和抗原多样性的认识。北美地区的 IAV-S 的特征是反复发生人类病毒溢出到猪群中，随后发生遗传和抗原多样化。需要解决的一个重要差距是我们对各种疫苗平台在针对抗原异源挑战的功效方面的作用的理解。目前许可的疫苗通常会更新其成分以适应动态的抗原景观，并且新开发的技术继续获得批准。因此，测试疫苗对具有不同抗原性的病毒的挑战的性能仍然至关重要。我们测试了甲型流感病毒载体血凝素（HA）亚单位疫苗在接种单价或双价疫苗后对猪流感病毒（IAV-S）的保护水平。单价甲型流感病毒载体 HA 疫苗对具有匹配和不匹配 HA 的病毒的挑战提供了有效的保护，尽管在一个不匹配 HA 的挑战组中，保护作用有降低的趋势。双价疫苗同时递送两种 HA，可有效产生针对两种抗原的抗体反应，并提供针对挑战的保护。甲型流感病毒载体是一种有前途的新技术，可提供给养猪户，以帮助减轻 IAV-S 引起的疾病负担。
