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Evaluation of infection in the older adult

Lona Mody, MD
Section Editor
Kenneth E Schmader, MD
Deputy Editor
Daniel J Sullivan, MD, MPH


Infection is the primary cause of death in one-third of individuals aged 65 years and older and is a contributor to death for many others [1]. Infection also has a marked impact on morbidity in older adults, exacerbating underlying illnesses and initiating functional decline.

Multiple biologic, cultural, and societal factors account for the increased susceptibility of older adults to infection and their poorer outcomes when infected. These factors also alter the presentation of infectious syndromes in older adults and may necessitate treatment modifications.

The aspects of infectious diseases unique to the older adult will be reviewed here. When available, recommendations for diagnostic evaluation and therapy for the older adult are provided. Multiple topics throughout UpToDate present detailed discussions of pathologic, diagnostic, therapeutic, and preventive aspects related to specific infections.


Fundamental alterations in quantitative and qualitative immune response occur with aging, a process that has been called immune senescence. (See "Immune function in older adults".)

Multiple age-related changes contribute to decreased protection from infection in older adults. These changes include:

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Literature review current through: Nov 2017. | This topic last updated: Dec 05, 2017.
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