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Influenza and Adults

Influenza (the “flu”) is a contagious viral infection primarily of the nose, throat, and lungs. Flu is caused only by the influenza virus, but many people confuse illnesses caused by other viruses or bacteria, including severe colds (rhinovirus) or “the stomach flu” (norovirus and other viruses and bacteria) with influenza.

Why Vaccinate Adults Against Influenza?

  • While the numbers vary, in the US each year, millions of people get sick, hundreds of thousands are hospitalized, and tens of thousands die from flu and related complications.
  • Influenza can cause serious complications in people with a variety of chronic illnesses, including asthma, diabetes, heart disease, and immunosuppression.
  • In the US, as many as one in five individuals get influenza each year, and while the virus can be mild in some years, it can be very severe in others, causing debilitating illness and death even in previously healthy people.
  • Every year flu affects employers and businesses and costs the US an estimated $11.2 billion in direct and indirect costs.

Which Adults Need Influenza Vaccine?

  • All adults need influenza vaccine every year.
  • The best time to get vaccinated is in the early fall, before influenza viruses begin spreading in the community. However, vaccination throughout the flu season is still beneficial.
  • Adults with certain health conditions including heart disease, asthma, diabetes, a liver or kidney disorder, or a weakened immune system are at especially high-risk for influenza and its complications. In most cases, they should also be vaccinated for pneumococcal disease.

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