Woman caring for a child in bed.

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 flu?

Symptoms of Colds and Flu

SymptomColdFlu
FeverAdults-rare; children- sometimesHigh fever (100°F and higher; can last 3 to 4 days)
Runny noseCommon (Nasal discharge may have a yellow- or green-colored tint)Sometimes
Stuffy noseCommonSometimes
HeadacheSometimes (usually mild)Common
Body achesSometimes (usually mild)Common (can be severe)
FatigueSometimes (usually mild)Common (can last up to 2-3 weeks)
ExhaustionNeverCommon (at the start of flu)
Chills, sweatNoCommon (extreme)
NauseaUncommonCommon
Loss of appetiteSometimesCommon
SneezingCommonSometimes
CoughCommonCommon (can be intense)
Sore throatCommonSometimes
Chest congestion, discomfortCommon (mild to moderate)Common (can be severe)
Watery eyesCommonSometimes

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