inactivated quadrivalent influenza virus split vaccine

The inactivated quadrivalent influenza virus split vaccine is an injectable vaccine designed for active immunization against influenza caused by two influenza A subtypes (H1N1, H3N2) and two influenza B lineages (Victoria and Yamagata)[6][8][3][2]. It is supplied as a split virion preparation, meaning that the virus is inactivated and then chemically disrupted to produce subviral particles, increasing safety and reducing reactogenicity[6][1]. The vaccine is formulated using either egg-based, cell-culture, or recombinant methods, depending on the manufacturer, and was designed to broaden coverage—especially in seasons where both B lineages circulate[4][1][7]. Its mechanism of action is the stimulation of a robust antibody-mediated immune response against the hemagglutinin proteins of the selected viral strains, thereby providing protection from seasonal influenza infection. Primary indications are prophylaxis of influenza in populations from 6 months of age and older[8][1][2][3][6]. Developers and manufacturers have included major vaccine companies such as GSK, Sanofi, Seqirus, and subsidiaries. Recent regulatory changes indicate a planned transition to trivalent vaccines after the extinction of one B lineage[4][5][7].

Brand names

Fluarix QuadrivalentFluzone High-Dose QuadrivalentFlucelvax QuadrivalentAfluria Quadrivalent

Other names

quadrivalent inactivated influenza vaccineQIVinactivated quadrivalent influenza virus split vaccine