With the second wave of COVID-19 underway, experts are saying the flu shot is more important than ever. Dr. Jennie Johnstone, Sinai Health’s Physician Lead for Infection Prevention and Control answers some of your questions about the flu and the flu shot.

When is flu season?
In Canada, most flu activity occurs during a period of 12 to 16 weeks sometime between November and March.

When is the best time to get the flu shot?
It’s a good idea to get the flu shot in October or November if you can, because your body takes some time to build up immunity after you receive the vaccination. It takes up to two weeks to get the full effect of the flu shot.

Even if you can’t get it early, you should still get the flu shot. The vaccine continues to be available throughout flu season.

Should kids get the flu shot?
Yes! The annual flu shot is recommended for everyone six months of age and older. Children under five years of age are one of the groups at higher risk of becoming seriously ill from influenza. They can develop ear infections, pneumonia, dehydration and febrile seizures.

Does the flu shot protect against COVID-19?
Although influenza and COVID-19 can have similar symptoms, the flu shot does not help prevent COVID-19 because influenza and COVID-19 are caused by two different types of viruses. The flu shot only provides protection against influenza viruses.

Scientists are working on developing a vaccine for COVID-19, but it will be a few months before it’s available. The best things we can do to prevent COVID-19 are cleaning our hands often, keeping a distance of two metres from people who aren’t part of our household and wearing a non-medical mask in public places. If you do feel even mild symptoms of a cold or flu-like illness, get tested for COVID-19 and stay home from your work, school or other activities.

If I have symptoms similar to a flu or a cold, how do I know if I should get tested for COVID-19? How can I tell the difference between COVID-19 and other respiratory illnesses such as influenza?
Influenza and other respiratory illnesses can have similar symptoms to COVID-19. The only way to tell the difference is by testing. If you have symptoms, make an appointment at a COVID-19 Assessment Centre to get tested. Use Ontario’s COVID-19 self-assessment tool for further guidance. The self-assessment tool also includes screening specifically for school-aged children, with guidance on when to stay home from school, getting tested and returning to school.

The similarity between symptoms of influenza and COVID-19 is one reason it’s more important than ever to get the flu shot this year. If we have a very active flu season, many people with flu-like symptoms will need to visit COVID-19 Assessment Centres to be tested. This would put a greater burden on Assessment Centres and the laboratories that process all of the tests.

Can I get the flu if I’ve already had it before?
Yes. There are several different strains of influenza virus and they change and evolve over time. Even if you’ve had the flu shot in previous years or you’ve been infected with influenza in the past, you could become infected again. This is why we all need to get the flu shot every year, before or during flu season. Scientists develop an updated version of the flu vaccine each year to provide protection against new strains of the virus.

For more questions and answers about the flu and flu shot, visit our flu information page.