Efficacy and uptake of the high-dose influenza vaccine for older adults: a literature review

Annual influenza epidemics are a significant contributor to morbidity and mortality in the United States and around the world. Older adults, individuals 65 years of age and older, are disproportionately affected by influenza. In 2009 a high-dose influenza vaccine was licensed for use in older adults. The efficacy and effectiveness of this influenza vaccine have been and continue to be studied today, in 2015. However, the CDC’s Advisory Committee on Immunization Practices (ACIP), the body primarily responsible for developing recommendations on how to use vaccines to control disease in the United States, recommends that older adults receive an influenza vaccine and does not distinguish between the standard-dose and high-dose vaccines. Given the growing body of research around the high-dose influenza vaccine, this literature review seeks to identify the efficacy of the high-dose influenza vaccine in older adults as well as facilitators and barriers to influenza vaccination among older adults. The author conducted a review of the literature published between January 1, 2004 and March 1, 2015 on these topics. Only 12 peer-reviewed articles were selected for inclusion from the 714 articles identified by the review. Four were randomized controlled trials, two were systematic literature reviews, four were retrospective data analyses, and two were cross-sectional studies. The studies regarding the efficacy of the high-dose influenza vaccine were of high quality, however the articles assessing factors associated with influenza vaccine uptake among older adults were limited in scope and generalizability. This review identified a considerable gap in the literature related to the facilitators and barriers to influenza vaccination among older adults at the individual, interpersonal, and community levels. Qualitative and mixed-methods research is needed to move from understanding who is and is not receiving an annual influenza vaccine to why and how individuals and communities are receiving annual influenza vaccines. This review is of public health significance because understanding and preventing influenza through the use of the high-dose influenza vaccine has the potential to significantly improve public health through preventing illnesses and hospitalizations, reducing influenza mortality, and reducing expenditures related to influenza morbidity