Education Materials

Mount Sinai Hospital is a University of Toronto patient care, teaching, and research centre.
Mount Sinai Hospital is a University of Toronto patient care, teaching, and research centre.

Frequently Asked Questions

» It's already January, is it not too late to get the flu vaccine?

No, receiving the vaccine now will protect you for the balance of the winter. Vaccine starts to give you some protection after 7-10 days. Since we are still just in the middle of the influenza season, getting vaccine now is still better than nothing.

» I got a flu shot last year and I still got the flu. Why take it this year?

Flu shots protect you well from the influenza strains in the vaccine (about 85% of all influenza), but not from ALL influenza, or from illness due to other viruses. Clinically, you cannot tell "flu like illness" due to other viruses from influenza. Thus, any one person cannot tell whether the flu shot is working. In tests in thousands of healthy persons, flu shots have been shown to reduce your chances of developing flu like illness by about 50% overall.

» I have already had the flu this year, why do I need to take the vaccination now?

First, the illness you have had may not have been influenza. However, even if you have had influenza, it will only have been due to one strain, and you will still be susceptible to other strains. Having the vaccination now will still protect you from further illness.

» I have heard that people actually get the flu from receiving the vaccine. Is this true?

The flu vaccines we have now are purified; that is, they are composed of only a few proteins of virus strains. The only side effect from the vaccine is a sore arm, which you can prevent by talking a dose of acetaminophen when you get your shot. Even if you have a cough or cold at the time you get your shot, your immune system will still work well enough to give you protection.

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