Seasonal Flu: Symptoms and Treatment

The seasonal flu (influenza) can cause severe illness or complications. Certain groups of people have a higher risk of developing serious health conditions from the flu.

Flu is most common during the fall and winter months. Peak levels generally occur between late December and early March. There are many different strains of flu, and they tend to change each year.

You can avoid the seasonal flu by getting vaccinated every year.

High-Risk Groups

Some people are more likely to get severely sick or have complications from seasonal flu. The following are high-risk groups:

  • Pregnant people
  • Children younger than 2 or adults 50 and older, especially adults older than 65
  • People with any of these medical conditions
    • Asthma or any other chronic respiratory diseases
    • Heart, kidney or liver disease
    • Obesity (a Body Mass Index of 40 and over)
    • Blood disorders, such as sickle cell anemia
    • Metabolic disorders
    • Weakened immune system, from illness or medication
    • Neuromuscular disorders that interfere with breathing or the discharge of mucus
    • Long-term aspirin therapy in people under 19
  • People living in nursing homes or other care facilities
  • American Indians and Alaskan Natives

People in these groups should call their health care provider if they have flu-like symptoms or have had recent close contact with someone with flu-like symptoms.


Flu symptoms usually start to show one to four days after exposure. Most people are ill for a few days.

Typical symptoms include fever, chills, aches, cough and sore throat. Intestinal symptoms, such as vomiting or diarrhea, are possible but less common. If you have a severe or worsening symptom, such as difficulty breathing, go immediately to a hospital emergency room.

Seasonal flu sometimes leads to serious complications, such as pneumonia, hospitalization or death.

Flu symptoms can be similar to COVID-19 symptoms. If you are experiencing these symptoms, get tested for COVID-19.


Most people recover from the flu on their own. You do not need to go to the hospital if you get the flu, but you should take the following steps to protect yourself and avoid infecting others:

  • Rest, drink plenty of liquids and take medications you would normally take to treat your symptoms. People 18 and younger should not take aspirin or aspirin-containing products, such as Alka Seltzer® or Pepto-Bismol. Aspirin can cause a rare but serious illness called Reye’s syndrome in young people with flu.

  • Stay home from work or school. Do not return until you have been free of fever for 24 hours.

  • Avoid close contact with other people. Stay away from crowded public places and avoid close contact with household members.

  • Cover your nose and mouth when you cough or sneeze.


There are several drugs that are used to prevent and treat seasonal flu. These medicines, which require a doctor’s prescription, are known as antivirals.

If you belong to a high-risk group and have flu-like symptoms or are in close contact with someone who has the flu, a health care provider may recommend that you take antiviral medicine as a precaution.

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