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Who Is Affected by Influenza

Who Is Affected by Influenza

The severity of the flu (influenza) varies widely from year to year. According to the Centers for Disease Control and Prevention (CDC):1

  • Influenza causes more than 220,000 hospital visits each year in the United States.
  • The number of cases of flu is highest during the winter months.
  • Children have the highest rates of infection.
  • Serious illness and deaths from the flu are highest in people ages 65 and older, children younger than 2 years of age, and people of any age who have medical conditions that place them at higher risk.

Because the flu virus is contagious, it spreads easily among people who live close together, such as in nursing homes and other long-term care facilities. The numbers of people affected and the death rates can be high.

Children younger than 5 and adults ages 65 and older are two of the groups who are most likely to be hospitalized for flu-related illness.

Flu and its complications caused an average of 36,000 deaths in the U.S. between 1990 and 1999.1



  1. Centers for Disease Control and Prevention (2010). Prevention and control of influenza with vaccines: Recommendations of the Advisory Committee on Immunization Practices (ACIP), 2010. MMWR, 59(RR-08): 1–62. Also available online: [Erratum in MMWR, 59(31): 993. Also available online:]


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

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