Why get vaccinated against influenza?
Influenza, also called the flu, can cause serious illness and can lead to hospitalization and even death. Influenza is ranked among the top 10 leading causes of death in Canada. Although the burden of influenza can vary from year to year, it is estimated that each year in Canada, influenza and its complications cause an average of 12,200 hospitalizations and approximately 3500 deaths.
Getting vaccinated is the best way to protect against influenza. When you get vaccinated, you help protect others as well by reducing the spread of the influenza virus.
How does the influenza vaccine work?
Influenza vaccines cause antibodies to develop in the body about two weeks after vaccination. These antibodies provide protection against infection with the viruses that are in the vaccine.
Influenza vaccines are designed to protect against the influenza viruses that research indicates will be most common during the upcoming influenza season. “Trivalent” influenza vaccines are made to protect against three different influenza viruses and “quadrivalent” vaccines are made to protect against four different influenza viruses.
Why do I need an influenza vaccine every year?
An influenza vaccine is needed every year because protection from the influenza vaccine declines over time. As well, influenza viruses are constantly changing so each year the influenza vaccine is reviewed and updated to protect you against the viruses circulating that year.
How well does the influenza vaccine work?
The influenza vaccine is the best way to protect against influenza. How well the vaccine works varies from season to season. It depends on how well matched the influenza vaccine is with the viruses circulating during the season and on the health status and age of the person being vaccinated. When the influenza vaccine is well matched with the circulating viruses, it prevents influenza in about 60% to 80% of adults and children receiving the vaccine. Effectiveness is less in the elderly population but studies have demonstrated that the influenza vaccine decreases the incidence of pneumonia, hospital admissions and death in the elderly population.