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Influenza (flu)

Influenza (flu) is a viral upper respiratory illness that comes on suddenly, causing a person to feel very sick with symptoms such as fever, body aches, headache, fatigue, loss of appetite, and a dry cough or sore, dry throat. Home treatment to reduce discomfort is usually all that is needed.

In some cases, the flu can lead to complications, such as bacterial pneumonia. People who are at high risk for complications include young children up to 5 years of age, adults age 65 and older, and all those who have certain health conditions, such as chronic heart or lung problems or immune system disorders.

Yearly immunization with the inactivated flu vaccine (flu shot) or the nasal spray vaccine (FluMist) helps reduce the risk of getting the flu and makes symptoms less severe for people who do get the flu.

ByHealthwise Staff
Primary Medical ReviewerE. Gregory Thompson, MD - Internal Medicine
Specialist Medical ReviewerChristine Hahn, MD - Epidemiology
Last RevisedJuly 8, 2010

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