Seasonal Influenza Vaccine 2021/2022 Provides Limited Cross Reactivity Against Contemporary Swine Influenza A Virus Strains in Spain

Swine influenza A viruses (SIVs) pose a zoonotic risk, with variants detected in humans in Europe. This study evaluated the efficacy of the 2021/2022 seasonal influenza vaccine against SIVs. Forty-six postvaccination human sera were tested via hemagglutination inhibition (HI) assay against Spanish S...

Descripción completa

Detalles Bibliográficos
Autores: Encinas, Paloma, Lalueza, Antonio, García-Vaquero, Ana Isabel, Nelson, Martha, García-Sastre, Adolfo, Real, Gustavo del
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2025
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/417011
Acceso en línea:http://hdl.handle.net/10261/417011
https://api.elsevier.com/content/abstract/scopus_id/105025436413
Access Level:acceso abierto
Palabra clave:Influenza A virus
Pandemic risk
Reverse zoonosis
Swine
Vaccine
Descripción
Sumario:Swine influenza A viruses (SIVs) pose a zoonotic risk, with variants detected in humans in Europe. This study evaluated the efficacy of the 2021/2022 seasonal influenza vaccine against SIVs. Forty-six postvaccination human sera were tested via hemagglutination inhibition (HI) assay against Spanish SIV genotypes. Seroprotection rate (SPR, HI titer ≥ 40) was 76% (95% CI: 64–88) and 91% (95% CI: 83–99) for human vaccine strains H1 and H3, respectively. SPRs were 67% (95% CI: 53–81) for pandemic swine H1, 64% (95% CI: 50–78) for human seasonal-like H1, 17%–46% for Eurasian avian-like H1, 15% (95% CI: 5–25) for human seasonal-like H3 from the 1970s, and 83%–93% for human seasonal-like H3 from the 2000s SIVs.