Initially, the flu may seem like a common cold with a runny nose, sneezing and sore throat. But colds usually develop slowly, whereas the flu tends to come on suddenly. And although a cold can be a nuisance, you usually feel much worse with the flu.

Common signs and symptoms of the flu include:

  • Fever over 100 F (38 C)
  • Aching muscles, especially in your back, arms and legs
  • Chills and sweats
  • Headache
  • Dry cough
  • Fatigue and weakness
  • Nasal congestion

When to see a doctor

If you have flu symptoms and are at risk of complications, see your doctor right away. Taking antiviral drugs within the first 48 hours after you first notice symptoms may reduce the length of your illness and help prevent more-serious problems.

Feb. 21, 2013

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