Influenza - the flu
What is influenza?
Influenza or "flu" is a viral infection of the nose, throat and bronchial tubes. There are two main types of influenza virus: A and B. Type A virus tends to cause more severe illness than type B. Each type includes many different strains which tend to change each year.
What are the symptoms of influenza?
Influenza usually comes on suddenly. Typical influenza symptoms include headache, fever, chills, tiredness, dry cough, sore throat, nasal congestion and body aches. Intestinal symptoms like nausea and vomiting may occur especially in young children. Although most people are ill for only a few days, some people have a much more serious illness, such as pneumonia, and may need to be hospitalized.
Is It a Cold or Influenza?

When does influenza occur?
Influenza occurs most often in the winter months. Illnesses resembling influenza may occur in the summer months but they are usually due to other viruses.
Who gets influenza?
Anyone can get influenza, but it is most serious in the high-risk patient/client/residents (frail elderly and/or persons with chronic illnesses such as heart, lung disease, AIDS or individuals receiving cancer treatments) who are particularly vulnerable to serious illness if they get ill from influenza.
How is influenza diagnosed?
Once influenza is known to be present in a community, the diagnosis can be made on the basis of the symptoms. Specific lab tests to confirm influenza are costly and time- consuming and are not needed for most cases.
How soon do symptoms appear?
The incubation period for influenza is one to four days.
How is it spread?
Influenza is very contagious and is easily spread through contact with droplets from the nose and throat of an infected person during coughing and sneezing. Influenza may also be spread when a person touches a surface that has influenza viruses on it – a door handle, for instance – and then touches his or her nose or mouth.
How long is a person able to spread influenza?
The contagious period varies, but probably begins the day before symptoms appear and extends for a week. It may be longer in infants and children.
Does past infection with influenza make a person immune?
Generally, no. The viruses that cause influenza change frequently, so people who have been infected or given an influenza ("flu") shot in previous years may become infected with a new strain. Because of this, and because any immunity produced by the influenza ("flu") shot may decrease in the year after vaccination, people should be re-vaccinated every year.
What you should do if you get the flu?
- Rest, drink plenty of liquids and avoid using alcohol and tobacco. Influenza is caused by a virus, so antibiotics (like penicillin) don’t work to cure it. Usually, influenza just has to run its course.
- The aches and fever can be treated with over-the-counter medicine like acetaminophen (Tylenol®). Children and teenagers with influenza should not be given any medicine containing acetylsalicylic acid (Aspirin®) because of the risk of a serious disease called Reyes Syndrome.
- Individuals at high risk may be treated with antiviral drugs (e.g. oseltamivir, amantadine). However these medications have to be prescribed by a physician early in the course of the illness.
When you should go and see your doctor?
- If you have trouble breathing, chest pain or cough that produces sputum which is bloody or rust-colored.
- If fever has lasted more than 3 to 4 days or is above 102˚F (39˚C) orally, in adults and children or 100.4˚F (38˚C) axillary (under the armpit), in children.
- If you are not starting to get better after a week or so.
- What can be done to control or prevent influenza?
What can be done to stop the spread or prevent influenza?
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Frequent hand washing with warm water and soap. This will reduce your chance of becoming infected after touching contaminated surfaces.
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Flu immunization in the fall. If you are over 65, chronically ill or a health care worker routine immunization against influenza (flu shot) is the most important control measure. When influenza occurs, an antiviral drug may be prescribed for prevention for certain people.
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Healthy eating, adequate sleep and physical activity are essential to your health and immune system.
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Cover your nose and mouth when you cough or sneeze. The influenza virus spreads quickly from person to person through droplets in the air. These droplets come from our noses and mouths, so it's important to cover them.
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Do not visit patients in hospitals or residents in personal care homes if you have influenza-like symptoms.
Can we go to work, school or daycare if our family has a cold or influenza?
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People with mild common cold symptoms (sneezing, runny nose and NO fever) may come to work. Practice good hand washing technique.
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People with influenza should not go to work until they are well enough to do so. Adults can continue to spread influenza virus for up to 5 days after start of symptoms.
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If your child attends daycare, tell the caregiver about any cold symptoms and ask if your child should stay away from daycare that day. Keep your child at home, away from daycare or school, if your child has a fever or if she is not well enough to participate in school or daycare activities.
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If your child attends daycare, tell the caregiver if you think your child has influenza. Keep your child at home, away from daycare or school, until the fever is gone and she is feeling better. Children can continue to spread influenza virus for about 7 days after start of symptoms.
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When both parents work outside the home, plan ahead by making arrangements for when your child becomes ill.
Wash your hands often with warm water and soap!
This will reduce your chance of becoming infected after touching contaminated surfaces.