Estimated influenza illnesses and hospitalizations averted by vaccination--United States, 2013-14 influenza season

Abstract

The Advisory Committee on Immunization Practices recommends annual influenza vaccination for all persons aged ≥6 months to reduce morbidity and mortality caused by influenza in the United States. CDC previously developed a model to estimate that annual influenza vaccination resulted in 1.1-6.6 million fewer cases and 7,700-79,000 fewer hospitalizations per season during the 2005-2013 influenza seasons. For the 2013-14 influenza season, using updated estimates of vaccination coverage, vaccine effectiveness, and influenza hospitalizations, CDC estimates that influenza vaccination prevented approximately 7.2 million illnesses, 3.1 million medically attended illnesses, and 90,000 hospitalizations associated with influenza. Similar to prior seasons, fewer than half of persons aged ≥6 months are estimated to have been vaccinated. If influenza vaccination levels had reached the Healthy People 2020 target of 70%, an estimated additional 5.9 million illnesses, 2.3 million medically attended illnesses, and 42,000 hospitalizations associated with influenza might have been averted. For the nation to more fully benefit from influenza vaccines, more effort is needed to reach the Healthy People 2020 target.