Vaccine effectiveness against influenza A(H3N2) and B among laboratory-confirmed, hospitalised older adults, Europe, 2017-18: A season of B lineage mismatched to the trivalent vaccine.
Angela M C RoseEsther KisslingAlin GherasimItziar CasadoAntonino BellaOdile LaunayMihaela LazărSierk D MarbusMonika KulieseRitva SyrjänenAusenda MachadoSanja Kurečić FilipovićLarrauri AmparoJesús CastillaValeria AlfonsiFlorence GaltierAlina IvanciucAdam MeijerAukse MickieneNiina IkonenVerónica GómezZvjezdana Lovrić MakarićAlain MorenMarta Valencianonull nullPublished in: Influenza and other respiratory viruses (2020)
IVE against influenza B was similar to A(H3N2) in hospitalised older adults, despite trivalent vaccine and circulating B lineage mismatch, suggesting some cross-protection. IVE was lower in those ≥80 than 65-79 years. We reinforce the importance of influenza vaccination in older adults as, even with a poorly matched vaccine, it still protects one in three to four of this population from severe influenza.