Influenza in Older Adults H. Keipp Talbot, MD, MPH INTRODUCTION Influenza viruses cause significant morbidity and mortality in older adults. Prevention and treatment are critical for the reduction of morbidity and mortality in this population, but there are several challenges in the diagnosis, treatment, and prevention of influ- enza infection and its complications in older adults. This article will describe influenza, its epidemiology, clinical presentation, diagnostic modalities, treatment, and current prevention techniques. Despite the identification of influenza early in the last century, much is still not known about how to protect older adults from influenza infection and its complications. Current treatment and prevention strategies are imperfect, particu- larly in older frail adults. VIROLOGY Influenza is a segmented RNA virus of the orthomyxoviridae family that circulates annually. 1 Influenza A and B are both known to cause disease in people. Because the virus is a segmented RNA virus, it has the capability of making minor (called anti- genic drift) or major (called antigenic shift) changes to its genome, causing seasonal or pandemic outbreaks of disease, respectively. Influenza A subtypes are differentiated by the type of hemagglutinin and neuraminidase found on their outer surface (eg, H1N1 and H3N2 subtypes). The hemagglutinin protein is responsible for viral receptor binding and fusion with the host respiratory epithelial cell. This surface protein un- dergoes frequent genetic mutations that allow for the circulating strain to potentially escape recognition by the host’s immune system. The neuraminidase, also a glyco- protein, facilitates the release of daughter virions from infected cells. For unknown Departments of Medicine and Health Policy, Vanderbilt University Medical Center, A2200 MCN, 1161 21st Avenue South, Nashville, TN 37232, USA E-mail address: [email protected] KEYWORDS Influenza Vaccine Aging Antivirals KEY POINTS Influenza viruses circulate yearly and cause significant disease in the elderly. Influenza often presents atypically in older adults. New influenza vaccines are being developed for older adults to overcome immune senescence. Infect Dis Clin N Am 31 (2017) 757–766 http://dx.doi.org/10.1016/j.idc.2017.07.005 id.theclinics.com 0891-5520/17/ª 2017 Elsevier Inc. All rights reserved.
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Related Documents
