Influenza (Flu)

What is the flu?

Influenza (the flu) is a respiratory infection caused by the influenza virus. The flu season (when most people get sick with the flu) often begins in late fall.

Learn More About the Flu

What are the symptoms of the flu?

After the germ enters the body, it can take 1-4 days before you may feel sick. Symptoms may include:

Photo of boy in bed with a thermometer in his mouth
  • Fever
  • Cough
  • Headache
  • Muscle aches
  • Stuffy and/or runny nose
  • Sore throat
  • Feeling unwell
  • Tiredness
  • For some children, nausea and vomiting may be present.

For the common cold, the symptoms are normally milder than the flu. Below is a resource that tells you the differences between the cold and the flu.

Who is at risk for complications from the flu?

Anyone can get the flu. Some people are at a higher risk for complications such as pneumonia, heart attacks, or in some cases, death. These individuals include:

  • Babies under 6 months old, because they are too young to get the flu shot.
  • Children under 5 years old, because their immune systems are still developing.
  • Individuals that are pregnant, because their immune system, heart and lungs change, especially later in pregnancy.
  • Indigenous peoples.
  • People 65 and older, because their immune systems are weaker and they are more likely to have an underlying condition that increases their risk.
  • People with underlying health conditions such as asthma, heart disease or diabetes.

How is it spread?

The flu mostly spreads by breathing in contaminated air from an infected person who is sneezing, coughing, or speaking. You can also get infected by touching your eyes, nose, or mouth with your hands after touching contaminated hands, surfaces, or objects. The germ can live up to 24 hours on surfaces.

How long is it contagious?

A person with the flu may be contagious the day before symptoms begins and up to 7 days after. Children and people with a weakened immune system may be contagious for even longer.

How is the flu treated?

For a healthy adult, your body's immune system should be able to fight off the flu virus on its own. Symptoms may last 7 to 10 days. If you get the flu:

  • Stay home and get plenty of rest
  • Drink lots of fluids
  • Avoid caffeine
  • Treat muscle pain using a hot water bottle of heating pad – apply heat for short periods of time
  • Take a warm bath
  • Gargle with a glass of warm salt water or suck on hard candy or lozenges
  • Use spray or saline drops for a stuffy nose
  • Avoid alcohol and tobacco
  • Speak to your healthcare provider or pharmacist about over the counter medications that can help you feel better (such as basic pain or fever relievers)

How is the flu prevented?

Photo of elderly woman getting flu shot

For almost everyone 6 months of age or older, the best way to protect yourself is to get the flu vaccine early. It can take up to 2 weeks for the vaccine to work. By getting it early in the flu season, you are protected when the season peaks. It is also important to get the vaccine every year as the virus changes and your immune response decreases within a year. You can get the flu vaccine from your health care provider, most walk-in clinics, or the pharmacy (for people 2 years of age and older).

Ways to prevent the spread of the flu include:

  • Wash your hands often for at least 15 seconds with warm water and soap. Avoid touching your eyes, nose, or mouth before you wash your hands.
  • Practice respiratory etiquette, such as coughing and/or sneezing into your elbow or tissue.
  • Stay at home when you're sick.
  • Do not share any personal items, such as cups and water bottles.
  • Clean and disinfect surfaces that are often touched by others such as door knobs, phones (viruses can live for 24-48 hours on hard surfaces). 


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