Flu Symptoms

Influenza, the "flu," is a highly contagious infection of the respiratory tract that can cause fatigue, muscle aches, fever and chills. The flu IS NOT just a severe cold, but a different infection caused by a different virus.

Get the Basics on Influenza (Flu)

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    Influenza (Flu)
    Flu can be mild or severe depending upon the type of virus, your age and overall health. Flu can affect many body systems, making you feel sick all over.

The Flu Can Wipe You Out

  • woman lying down; feeling ill, malaise, fatigue
    Weakness may be subjective (feeling weak with no measurable loss of strength).

The Flu Can Hurt

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    Muscle aches
    Muscle pain can be a sign of conditions affecting your whole body, like some infections (including the flu).

The Flu Can Leave You Hot or Cold

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    Chills may occur at the beginning of an infection and often predict the coming of a fever, or an increase in the body's core temperature.

It Might Not Be The Flu

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    Cold Symptoms
    Sneezing, runny nose, nasal congestion, coughs and sore throat are all symptoms of the common cold. Compare your symptoms to those commonly associated with the cold.

All About Swine Flu

Swine Flu: The H1N1 Influenza Virus

Swine flu
Get newly updated information on the swine flu H1N1 virus and information on swine flu cases, symptoms, treatments, and vaccines.
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What Could Your Symptoms Mean?

Symptom Checker

Check a Symptom
Check your symptoms here to help find out if you've got the cold or the flu, allergies, or another respiratory infection.
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