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Flu
 Understanding Flu
  Definitions and Overview
  Cause
  Transmission
  Symptoms
  Complications
  Diagnosis
  Treatment
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Flu (Influenza)

Complications

You can have flu complications if you get a bacterial infection, which can cause pneumonia in your weakened lungs. Pneumonia also can be caused by the flu virus itself.

Complications usually appear after you start feeling better. After a brief period of improvement, you may suddenly get these symptoms

  • High fever
  • Shaking chills
  • Chest pain with each breath
  • Coughing that produces thick, yellow-greenish-colored mucus

Pneumonia can be a very serious and sometimes life-threatening condition. If you have any of these symptoms, you should contact your health care provider immediately to get the appropriate treatment.

Flu Complications In Children And Teenagers

Reye's syndrome, a condition that affects the nerves, sometimes develops in children and teenagers who are recovering from the flu. Reye's syndrome begins with nausea and vomiting, but the progressive mental changes (such as confusion or delirium) cause the greatest concern.

The syndrome often begins in young people after they take aspirin to get rid of fever or pain. Although very few children develop Reye's syndrome, you should consult a health care provider before giving aspirin or products that contain aspirin to children. Acetaminophen does not seem to be connected with Reye's syndrome.

Other Complications Of The Flu That Can Affect Children

  • Convulsions caused by fever
  • Croup
  • Ear infections, such as otitis media

Newborn babies recently out of intensive care units are particularly vulnerable to suffering from flu complications.

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Volunteer for NIAID-funded clinical studies related to flu on ClinicalTrials.gov.

Related Links

View a list of links for more information about influenza.

See Also

Influenza news releases

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Volunteer for NIAID-funded clinical studies related to flu on ClinicalTrials.gov.

Related Links

View a list of links for more information about influenza.

See Also

Influenza news releases