Trivalent and quadrivalent MF59(®)-adjuvanted influenza vaccine in young children : a dose- and schedule-finding study.

Young children are at increased risk for influenza infections and related complications. The protection offered to children by conventional trivalent inactivated influenza vaccines (TIV) is suboptimal, due to poor immunogenicity and a higher exposure to infection and complications in this age group, particularly from influenza B strains. In this dose-ranging, factorial design trial, we report the safety and immunogenicity of different combinations of adjuvanted (ATIV) and non-adjuvanted trivalent (TIV) and quadrivalent (QIV) influenza vaccines in 480 healthy children 6 to