Adjuvanted versus nonadjuvanted influenza vaccines in young children: comparing results from recent clinical trials

A relatively high burden of influenza is experienced by young children. In order to successfully tackle the burden of influenza in children, effective vaccines are necessary. Accumulated evidence on the efficacy and effectiveness of traditional inactivated split or subunit trivalent influenza vaccines points towards no significant protection in the youngest children, who are largely unprimed. Adjuvanted influenza vaccines have been developed to improve the immune response, and could possibly overcome limitations of traditional influenza vaccines in the youngest age groups. In this review, evidence from recent clinical trials of adjuvanted versus nonadjuvanted influenza vaccines in children younger than 3 years of age will be discussed. Important findings from identified studies will be highlighted, and ongoing challenges concerning the use of adjuvanted influenza vaccine in young children will be discussed.