Immunogenicity and safety of 1 versus 2 doses of quadrivalent-inactivated influenza vaccine in children aged 3-8 years with or without previous influenza vaccination histories.

ABSTRACT: This study assessed the immunogenicity and safety of a quadrivalent influenza split-virion vaccine (IIV4) in children with and without prior influenza vaccination. An open-label, phase IV clinical trial was conducted in healthy children aged 3-8 years in Pizhou, Jiangsu Province, China. Children with ≥2 doses of prior influenza vaccination (Influenza Vaccination Group) and those with no prior vaccination (Influenza Vaccine-naïve Group) were given two doses of IIV4, 4 weeks apart. The primary immunogenicity endpoints were seroprotection rates (SPRs) of hemagglutination inhibition antibody 28 days after each dose against influenza A/H1N1, A/H3N2, B/Yamagata (BY), and B/Victoria (BV). Safety endpoints included adverse events (AEs) within 28 days and serious adverse events (SAEs) within 6 mont

SUBMITTER: Wen F 

PROVIDER: S-EPMC11853548 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature