PIH41 - Cost-Effectiveness Of Quadrivalent Versus Trivalent Influenza Vaccines For Children

Abstract

Influenza could cause serious consequences, especially on children. The WHO recommended that influenza vaccination of children is the most effective means. Trivalent influenza vaccine (TIV), which contains two lineages of influenza A virus and one lineage of influenza B virus, is now use as a first-line strategy to prevent influenza in Taiwan. However, when the influenza B-lineage included in the TIV mismatched with circulating strains, the protection of TIV would be reduced. Quadrivalent influenza vaccine (QIV) which includes both influenza B viruses of the two circulating lineages is thus proposed as an alternative. The aim of the study was to assess, from the governmental perspective, the cost-effectiveness of using QIV versus TIV as an influenza vaccination for children under 17 years old. A Markov model was used to assess the cost and effectiveness of QIV and TIV. Cost data were obtained from the National Health Insurance claims data. Vaccine efficacy and transition probability of different health states were based on previous studies. Outcomes included cases avoided, life-years gained, QALYs gained and the corresponding incremental cost-effectiveness ratios (ICERs). The discount rate of cost and effectiveness was set at 3.5% and the time horizon used in the model is 100 years. The avoided influenza-associated outcomes form QIV, compared to TIV, and throughout the estimate lifetime were as follows: 251,512 influenza cases avoided, 32,355 cases with influenza complications avoided, 254,855 outpatient visits avoided, 3,860 inpatients receiving treatment for complications avoided and 717 deaths avoided. The ICER of this alternative, compared with TIV, was US$44,231.3 per QALY gained. When the herd effect was taken into consideration, the ICER dropped to US$30,947.85 per QALY gained. From the governmental perspective, the QIV of seasonal influenza is associated with favorable cost-effectiveness ratios in children under 17 years.