Modeling the Effect of Different Vaccine Effectiveness Estimates on the Number of Vaccine-Prevented Influenza-Associated Hospitalizations in Older Adults

We compared influenza vaccine-prevented hospitalizations in adults aged >= 65 years for a range of hypothetical effectiveness estimates. During 2012-2013, a vaccine with 10% effectiveness (66% coverage) would have averted approximately 13 000 hospitalizations, and a vaccine with 40% effectiveness would have averted approximately 60 000 hospitalizations. Annual vaccination is merited in this vulnerable population.