The Importance of Frailty in the Assessment of Influenza Vaccine Effectiveness Against Influenza-Related Hospitalization in Elderly People

Influenza is an important cause of morbidity and mortality among older adults. Even so, effectiveness of influenza vaccine for older adults has been reported to be lower than for younger adults, and the impact of frailty on vaccine effectiveness and outcomes is uncertain. Researchers aimed to study vaccine effectiveness against influenza hospitalization in older adults, focusing on the impact of frailty.