Preventing Infections and Healthy Aging

Dysregulated immune function in older adults is a hallmark of aging and affects the ability of this vulnerable population to resist infection and respond to vaccination. Pneumonia and influenza are the leading causes of hospitalization and death from infectious disease, and lower respiratory tract infections are the third leading cause of death worldwide (WHO, Media centre fact sheets. Available at: http://www.who.int/mediacentre/factsheets/fs310/en/index.html. Accessed 18 Mar 2018). The decline in immune function with aging is now recognized as being more than immunosenescence. Inflammatory processes associated with the immune response are critical to protection against severe infections, but tissue damage occurs when this response becomes chronic. As we grow older, our ability to regulate this response declines, which leads to the accumulation of high levels of inflammatory mediators circulating in the blood and ongoing tissue damage – this process defines “inflammaging” and appears to be fundamentally implicated in the accelerated progression of chronic diseases, functional decline, and loss of resilience with aging. This chapter will focus on vaccine preventable disability and the current recommendations for vaccination in the population age 50 and older who bear the greatest burden of multiple chronic conditions. Primary, secondary, and tertiary prevention strategies to address the challenges of pneumonia and influenza and herpes zoster start with vaccination and the basics of healthy diets, exercise, and smoking cessation in an aging population.