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Find out how long a person who has the flu is contagious and how long symptoms may last.

Reviewed 4/1/2024

Flu infection facts

Find out how long a person who has the flu is contagious and how long symptoms may last.

The flu virus enters the body:

The flu can spread to others up to about 6 feet away, typically when an infected person sneezes, coughs or talks.

Symptoms begin 1-4 days after the virus enters the body.

Contagious:

To avoid spreading the flu, limit contact with other people. Cover your nose and mouth with tissue when you cough or sneeze. Throw the tissue away.

Contagiousness starts 1 day before symptoms start. Lasts 6-8 days.

Flu symptoms:

Flu symptoms may include: fever and/or chills, cough, sore throat, runny or stuffy nose, muscle or body aches, headache, fatigue, vomiting, and diarrhea. If you are very sick or worried about your illness, contact your healthcare provider.

Symptoms last a few days but may persist up to 2 weeks.

Sources

Centers for Disease Control and Prevention. "Flu Symptoms & Complications." https://www.cdc.gov/flu/symptoms/symptoms.htm.
Centers for Disease Control and Prevention. "Flu: What To Do If You Get Sick." https://www.cdc.gov/flu/treatment/takingcare.htm.
Centers for Disease Control and Prevention. "How Flu Spreads." https://www.cdc.gov/flu/about/disease/spread.htm.