Flu - Complications of flu

Complications of flu mostly affect people in high-risk groups, such as the elderly, pregnant women and those who have a long-term medical condition or weakened immune system.

The most common complication is a bacterial chest infection. Occasionally, this can become serious and develop into pneumonia.

A course of antibiotics usually cures a chest infection or pneumonia, but it can very occasionally become life threatening, particularly in the frail and elderly.

Other serious complications are uncommon.

Rare complications

Rare complications include:

  • tonsillitis
  • otitis media – a build-up of fluid in the ear
  • septic shock – infection of the blood that causes a severe drop in blood pressure
  • meningitis – infection in the brain and spinal cord
  • encephalitis – inflammation of the brain

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