1. What is Influenza?
2. Is Influenza contagious?
3. Is Influenza serious?
4. How can I prevent influenza?
5. Tell me about the flu shot?
6. Do the flu shots change from year to year?
7. What is a pandemic?
8. What is bird flu?

What is Influenza?

Influenza (commonly called the flu) is a highly contagious respiratory illness caused by influenza viruses  that can occur in children or adults of any age. It is responsible for illness in up to 20 percent of people worldwide each year.  It occurs most frequently in the winter months and usually peaks in the months of November & March.

Is Influenza contagious?

The virus is spread easily from person-to-person via infected respiratory secretions. As a result, attack rates can be particularly high among individuals living in an institutionalized setting such as schools or long term care facilities, including nursing homes.

Is Influenza serious?

Influenza can cause mild to severe illness, and at times can lead to death. Serious illness is more likely in the very young, the elderly, and people who have certain underlying health conditions such as malnutrition, asthma or other forms of lung disease.

In the USA: 5% - 20% of the population gets the flu every year.  Approximately 36,000 people die each year from flu.  More than 200,000 people are hospitalized from flu complications; more than half of these are people 65 years and older, 20,000 of those hospitalized are children younger than 5 years old. 

Up to 10% of all deaths during flu season are related to influenza complications

In Quebec 15% - 20% of the population gets the flu every year. Approximately 1,500 people die each year from flu.

In Canada an estimated 10-25% of Canadians may get the flu each year. 

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How can I prevent influenza?

Influenza is best prevented by the influenza vaccine, as well as with simple infection control measures such as hand washing. Antiviral medications can also help prevent infection after exposure, but are generally reserved for patients at risk for complications.

Tell me about the flu shot?

Flu vaccines have been around since the 1940s.

Influenza vaccine is effective in reducing the chance of contracting the flu.
Patients who receive vaccine form antibodies (proteins), which destroy the virus after the person is exposed; it generally takes about two weeks to make these antibodies. If the circulating virus and strains used for the vaccine match closely, the vaccine can protect 50 to 80 percent of vaccinated individuals from getting the flu.

After you get a flu shot, your immune system produces antibodies against the strains of virus in the vaccine. The antibodies are effective for four to six months. When you are exposed to the flu virus, the antibodies help prevent infection or reduce the severity of the illness.

Do the flu shots change from year to year?

The influenza vaccine requires approximately nine months to be manufactured. As a result, each year's vaccine is based on the previous year's flu virus and viral strains known to be circulating in other parts of the world. The vaccine's effectiveness for the current year's flu, therefore, depends upon how well scientists are able to predict which strains will cause infection in a given year. 

What is a pandemic?

There have been several severe and extensive flu outbreaks in the twentieth century (called pandemics), which led to the deaths of millions of people worldwide. These were caused when influenza viruses arose (often from animals or birds in Asia), to which humans had no prior experience, and thus no immunity.

A pandemic (caused by a different virus) in 1918 was responsible for millions of deaths worldwide.

What is bird flu?

Avian influenza (bird flu) is caused by a strain of influenza virus to which humans had apparently not been exposed prior to 1997, although this is controversial. There are several strains of avian influenza; one strain H5N1 virus is the cause of recent concern, since it has resulted in several deaths, mostly in Asia.
To date, avian influenza has primarily spread from bird-to-bird, and much less commonly from bird-to-human; human-to-human transmission has occurred rarely. The risk of human infection is related to the close proximity of humans and poultry in certain areas.