Immunizations in Older Adults

The age-related decline in immunity known as immunosenescence means that older adults are at increased risk of infection, as well as at higher risk of severe forms, complications, and poor outcomes. In parallel, the burden of infectious diseases is highest among older adults, with the inherent risk of hospitalization, aggravation of pre-existing diseases, frailty, increased disability, and ultimately death. Vaccination is the most effective means to prevent against common infectious diseases, yet vaccine uptake in adults remains consistently below target. We discuss here the physiopathological rationale for vaccination in older adults, focusing on the three main diseases that account for the greatest morbidity and/or mortality in this population, namely, seasonal influenza, pneumococcal disease, and herpes zoster. We discuss the burden of each disease and the available vaccines. We also briefly review other vaccines recommended in older adults. The role of the family physician in promoting vaccination among older adults is key and can actively drive efforts to improve vaccine uptake in this population, thereby reducing the burden of infectious disease and contributing to healthy aging.