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Influenza (“the flu”) is a viral respiratory infection that spreads from person to person.
Influenza is an illness caused by the influenza virus, which infects the nose, throat, and sometimes lungs. It spreads from person to person by coughing and sneezing. It may also be transmitted by direct contact with infected individuals or contaminated objects. Influenza can cause mild to severe illness, including complications such as pneumonia, hospitalization, or death.
Signs and symptoms of influenza
- Fever (100°F or higher)
- Fatigue or tiredness
- Stuffy or runny nose
- Cough
- Chills
- Headache
- Sore throat
- Body aches
Symptoms typically begin 1 to 3 days after being exposed to the influenza virus. Most individuals feel better within a few days, but cough and fatigue may last two weeks or more.
Some people are at higher risk of developing flu complications if they get sick
Groups at higher risk for flu complications include:
- Children younger than age 2 years, or adults 65 years or older
- Individuals with certain medical conditions, like asthma or other chronic lung disease, or those with weakened immune systems
- Pregnant persons or those who will be pregnant during the influenza season
- People who live in nursing homes and other long-term care facilities
What to do if you have the flu or symptoms of the flu
- Stay home and avoid contact with other people except to get medical care.
- Check with your doctor promptly if you are in a group at high risk for serious complications and you get flu symptoms, or if you are very sick with flu symptoms.
- There are prescription medications called “antiviral drugs” that can be used to treat influenza illness, and work best when taken within 2 days of symptoms starting. Prompt treatment is recommended for people who have flu or suspected flu and who are at increased risk of serious flu complications.
Yearly flu vaccination is the best way to protect yourself and others from the flu.
Everyone aged 6 months and over should receive an influenza vaccine every year.
There are also everyday steps you can take to protect your health and if you are sick, to prevent spreading influenza to others, including:
- Wash your hands often with soap and water, especially after coughing or sneezing. Alcohol-based hand sanitizers are also effective.
- Avoid touching your eyes, nose or mouth.
- Cover coughs and sneezes.
- Avoid close contact with people who are sick.
- If you are sick with influenza-like illness, stay home for at least 24 hours after your fever has resolved without the use of fever-reducing medication and symptoms are improving, except to get medical care or for other necessities.
