Maximizing public health benefits: Policy perspectives on coverage and cell-based influenza vaccines in the US

Cell-based influenza vaccines can increase vaccine effectiveness by avoiding egg adaptations associated with traditional egg-based manufacturing techniques. This study evaluated the impacts of switching from use of an egg-based trivalent influenza vaccine (TIVe) to a cell-based vaccine (TIVc) for vaccination of individuals <65 y of age in the US. We used a dynamic age-stratified susceptible-exposed-infectious-recovered model combined with an age-structured decision tree model to compare the health and economic impacts of using TIVc in individuals <65 y combined with adjuvanted trivalent influenza vaccine (aTIV) in older adults (≥65 y) with two baseline scenarios: 1. vaccination of all individuals with TIVe; 2. vaccination of individuals <65 y with TIVe and ≥65 y with aTIV. Use of TIVc+aTIV resulted in substantial reductions in influenza burden across all vaccine coverage levels evaluated, with 8.5 million cases, 127,000 hospitalizations, and 19,000 deaths averted compared with TIVe at 65% coverage. The combination of TIVc and aTIV was cost-saving compared with either baseline scenario, irrespective of vaccine coverage level. Analysis by age group showed that TIVc+aTIV was either cost-effective or cost-saving across all pediatric and adult age groups, with greatest direct cost benefits seen in adults 50-64 y. Overall, our findings support the preferential use of TIVc over TIVe in individuals <65 y in vaccination programs, along with inclusion in programs together with an enhanced vaccine in adults ≥65 y.