What are colds and the flu?

The common cold and the flu (influenza) are infections of the upper respiratory system - the nose, mouth, throat, and lungs. The infections are caused by viruses.

How can I tell if I have a cold or the flu?

Colds and flu have many of the same symptoms. However, cold symptoms are usually milder than flu symptoms and develop more slowly.

What are the symptoms of colds and the flu?

Symptoms of colds and flu include:

Symptoms of Colds and Flu

  • Symptom: Fever
    • Cold: Adults - rare; Children - sometimes
    • Flu: High fever (100°F and higher; can last 3 to 4 days)
  • Symptom: Runny nose
    • Cold: Common (Nasal discharge may have a yellow- or green-colored tint)
    • Flu: Sometimes
  • Symptom: Stuffy nose
    • Cold: Sometimes (usually mild)
    • Flu: Common
  • Symptom: Headache
    • Cold: Sometimes (usually mild)
    • Flu: Common
  • Symptom: Body aches
    • Cold: Sometimes (usually mild)
    • Flu: Common (can be severe)
  • Symptom: Fatigue
    • Cold: Sometimes (usually mild)
    • Flu: Common (can last up to 2-3 weeks)
  • Symptom: Exhaustion
    • Cold: Never
    • Flu: Common (at the start of the flu)
  • Symptom: Chills, sweat
    • Cold: Never
    • Flu: Common (extreme)
  • Symptom: Nausea
    • Cold: Uncommon
    • Flu: Common
  • Symptom: Loss of appetite
    • Cold: Sometimes
    • Flu: Common
  • Symptom: Sneezing
    • Cold: Common
    • Flu: Sometimes
  • Symptom: Cough
    • Cold: Common
    • Flu: Sometimes
  • Symptom: Sore throat
    • Cold: Common
    • Flu: Sometimes
  • Symptom: Chest congestion, discomfort
    • Cold: Common (mild to moderate)
    • Flu: Common (can be severe)
  • Symptom: Watery eyes
    • Cold: Common
    • Flu: Sometimes