Prioritization of influenza vaccine intervention.

Prioritization of influenza vaccine intervention among different age and risk groups based on different criteria: risk of death, total deaths, net benefits, and return on investment. aRisk of death is estimated based on the number of influenza related deaths per 100,000 subpopulation for the specific age and risk groups. Risk of death is the highest among the high risk 65+ years subpopulation in the catastrophic influenza and it is the highest among high risk 0–19 years subpopulation in the strong, and moderate influenza pandemic scenarios. bTotal deaths is estimated based on the proportion of influenza related deaths for the specific age and risk groups among total influenza related deaths. The proportion of influenza related deaths is the highest among the high risk 20–64 years subpopulation in the catastrophic, strong, and moderate influenza pandemic scenarios. cNet benefits are the difference in cost due to improved health outcomes from vaccination and the vaccination cost. Net benefits are the highest among the high risk 20–64 years subpopulation in the catastrophic, strong, and moderate influenza pandemic scenarios. dReturn on investment is the gain in net benefits relative to the vaccination cost, that is, dollars saved per $1 investment in vaccine intervention. Return on investment is highest among the high risk 0–19 years subpopulation in the catastrophic, strong and moderate influenza pandemic scenarios.