Influenza

Seasonal Influenza (flu)

​What is influenza (also called ‘flu’)?​​​​

The flu is a contagious respiratory illness caused by influenza viruses. It can cause mild to severe illness, and at times can lead to death.

Every year in the United States, on average:

  • 5% to 20% of the population gets the flu;
  • more than 200,000 people are hospitalized from flu complications, and;
  • about 36,000 people die from flu.

The best way to prevent the flu is by getting a flu vaccination each year.

Vaccination of high-risk persons is especially important to decrease their risk of severe flu illness. People at high risk of serious flu complications include young children, pregnant women, adults 65 years and older; and people with certain chronic conditions like asthma, diabetes or heart and lung disease.

Everyday actions to stop the spread of germs can also help prevent the spread of flu (see “Preventing Influenza").

Flu is different from a cold. Flu usually comes on suddenly. Symptoms of flu include:

  • fever* (usually high) or feeling feverish/chills
  • headache
  • extreme tiredness
  • dry cough
  • sore throat
  • runny or stuffy nose
  • muscle aches
  • stomach symptoms such as nausea. Vomiting and diarrhea can also occur but are more common in children than in adults.

*It is important to note that not everyone with flu will have a fever.

If you are sick with flu, antiviral drugs can be used to treat your illness. Antiviral drugs are prescription medicines and are not available over the counter. These drugs can make your illness milder and shorten the time you are sick, and may also prevent serious flu complications. Antivirals are most effective when taken within 48 hours of getting sick but starting them later may still be helpful. For more information please visit, Influenza (Flu) | CDC.