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Flu (Influenza)

The flu (also known as influenza) is a respiratory infection that is caused by a virus. People of any age can get influenza. Most people are sick for 2 to 7 days, although coughing may last for weeks. Influenza can lead to complications such as pneumonia, hospitalization, and even death. The elderly, young children and those with long-term health issues, such as heart and lung problems, diabetes and cancer, are more likely to develop these complications.

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    Flu shots are available at healthcare provider offices and participating pharmacies. Find a participating flu shot clinic near you.

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What are the Signs and Symptoms of the flu?

People with influenza quickly become sick with:

  • cough, 
  • fever, 
  • sore throat, 
  • headache, 
  • muscle aches and 
  • tiredness

How does the flu spread to others?

Influenza spreads easily from infected people to others through coughing and sneezing. It can also be picked-up by touching unwashed hands and from surfaces and objects such as toys.

How can I protect myself from the flu?

It is not always possible to prevent becoming sick with the flu but there are a few things that you can do to reduce your risk of illness.

1. Clean Your Hands

The most important thing you can do to prevent illness is to clean your hands frequently with soap and water or alcohol-based hand sanitizers. Alcohol-based hand sanitizers should contain 60-90% alcohol. Hands should be cleaned after handling tissues, blowing your nose, shaking hands, touching objects around you and before preparing and eating food.

2. Get the flu shot

The flu shot is the best way to reduce your risk of getting sick with influenza and spreading it to others. In elderly people, the vaccine can prevent pneumonia, hospitalization and death. It is important to get your flu shot early. Protection from the vaccine develops around two weeks after receiving it. Protection from influenza may last up to one year. People who receive the vaccine can still get influenza, but if they do, it is usually milder. However, the vaccine will not protect against colds and other respiratory illnesses that may be mistaken for influenza.

3. Stay home if you feel sick

Sick people who go to work, school and other public places can spread their illnesses to others. Staying home when you are ill is important to help reduce the spread of influenza. You can return to work or school one day after you are symptom free. 

4. Cover your cough (PDF)

Coughing and sneezing can spread germs to others. Cough or sneeze into a tissue and throw it away. If you don’t have a tissue, cough or sneeze into your sleeve. Always clean your hands after coughing or sneezing,

5. Clean surfaces

Frequently clean and disinfect surfaces that are touched a lot like doorknobs, keyboards, counter tops, sink taps, etc. 

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We do more than…

Health Unit Finger Character

2016 Seasonal Influenza Fact Sheet →


The Story of Influenza

Infographic: The Story of Influenza

Enlarge image →


What is the difference between a cold and the flu?

Symptoms of the common cold and the flu are often very similar. However, colds do not generally result in serious health problems such as pneumonia or bacterial infections.

Please note: Children may also experience croup, ear infections, nausea, vomiting and diarrhea when they have the flu. These symptoms are not common in adults.






Usual; high fever (102 ° F/39 ° C - 104 ° F, 40 ° C), sudden onset, lasts 3 to 4 days.



Usual; can be severe

Muscle aches and pains

Sometimes, generally mild

Usual; often severe

Tiredness and weakness

Sometimes, generally mild

Usual; severe, may last up to 2 to 3 weeks

Extreme tiredness


Usual; early onset, can be severe

Runny, stuffy nose






Sore throat



Chest discomfort, coughing

Sometimes, mild to moderate

Usual, can become severe.


Can lead to sinus congestion or infection, and ear aches.*

Can lead to pneumonia and respiratory failure, and become life-threatening. Can worsen a chronic condition.


Frequent hand washing

Annual immunization and frequent hand washing

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If you have questions about the flu and would like to speak to a health professional, call the Infectious Disease Control Team at 519 663-5317 ext 2330.

Date of creation: February 27, 2013
Last modified on: June 1, 2018