FAQs
Find answers to frequently asked questions about COVID-19 vaccination.
Book your next dose today!
Find answers to frequently asked
questions about vaccination with
COMIRNATY and COMIRNATY
Original & Omicron BA.4/BA.5.
Book your next dose today!
New vaccine formulations
Why is it important to get a COVID-19 vaccine?
The virus that causes COVID-19 has evolved over time and some of these changes have created new variants of concern. Manufacturers have updated their vaccines to help provide protection against SARS-CoV-2.
It is recommended to receive a dose of a latest formulation of COVID-19 vaccine to help update your immune response to the virus. Talk to your healthcare provider about which vaccine is appropriate for you.
Other concerns you may have
“I don’t need to receive a booster – my primary vaccination series should provide me with enough protection against COVID-19.”
COVID-19 vaccines have been shown to be effective in helping to prevent the disease in individuals. However, COVID-19 is constantly evolving and over time, the immune response may start to decrease. Vaccination with an additional dose may increase this immune response against SARS-CoV-2.
“I have had a COVID-19 infection and I was vaccinated; I’m covered.”
Even if you've had COVID-19, vaccination is still very important. While infection alone provides some protection, vaccination after infection can help improve the immune response. It's recommended that you receive a dose of the latest formulation of COVID-19 vaccine at 3 or more months after you had a COVID-19 infection and/or since your last vaccination. Please see the recommendations in your province for more information.
“I already received an additional dose with a Pfizer-BioNTech COVID-19 vaccine.”
COVID is constantly evolving and over time, the original immune response may start to wane. If it has been at least 3 months since you previously received an additional dose of COMIRNATY, it may be time to book your next dose with a latest formulation of COVID-19 vaccine, like COMIRNATY.
Additional doses
Why is it important to get an additional dose?
The COVID-19 vaccines have been demonstrated to be effective in helping to prevent the disease in individuals. However, over time, the immune response may start to decrease. Additional doses may increase this immune response against the SARS‑CoV‑2 virus. It is recommended to receive a dose of a recent formulation COVID-19 vaccine if you have previously been vaccinated.
Who can receive an additional COVID-19 vaccination dose?
At least one additional dose continues to be recommended for all adults 18 years of age and over. All previously vaccinated individuals in all authorized age groups should receive a dose of a latest formulation of COVID-19 vaccine.
Read the National Advisory Committee on Immunization’s recommendations.
What side effects can I expect after vaccination with COMIRNATY?
The most common side effects (may affect more than 1 in 10 people) include: irritability (6 months to <2 years), pain/tenderness, swelling at the injection site, tiredness, headache, muscle pain, chills, joint pain, fever, and diarrhea.
Learn more
Can children receive an additional dose?
Yes. Children aged 5 through 11 years may receive an additional COVID-19 dose at least 6 months after their last dose. Children aged over 12 years may receive an additional dose at least 3 to 6 months after their last dose.
Can pregnant women receive an additional dose?
It may be possible to receive a COVID-19 vaccine at any stage during pregnancy. It is important to talk to your doctor to determine whether vaccination, and which vaccine, is right for you.
Immunization is particularly important for those at increased risk of infection or severe disease, including individuals who are pregnant.
To help avoid side effects and ensure proper use, talk to your healthcare professional before you receive an additional dose, and inform them if you are pregnant or plan to become pregnant.
Learn more
When should I get my additional dose?
An additional dose may be administered to people aged 5 years and older, 3-6 months after completion of the primary series or a previous additional dose of COMIRNATY. The minimum interval is 3 months from the last dose. This minimum interval of 3 months will ensure that those who receive a spring 2024 dose will be eligible again for an updated fall 2024 dose when it becomes available
Read the National Advisory Committee on Immunization’s recommendations.
How long does my protection against COVID-19 last?
Evidence indicates that the vaccines used in Canada are effective at preventing COVID-19. An additional dose following a primary series of mRNA vaccines is recommended in people aged 5 year and older. More data are needed from ongoing and additional studies in the long term to understand how long protection lasts after COVID-19 immunization.
Receiving all your recommended doses provides protection which may decrease over time. This is why it is important to receive an additional dose, when eligible, to help increase the immune response against SARS-CoV-2.
Primary vaccination series
Is COMIRNATY the same as the Pfizer-BioNTech COVID-19 vaccine?
COMIRNATY COVID-19 mRNA Vaccine is the official name of the Pfizer-BioNTech COVID-19 vaccine.
Who can receive the primary COVID-19 vaccination series?
COVID-19 vaccination with a recently updated COVID-19 vaccine is recommended for individuals at increased risk of SARS-CoV-2 infection or severe COVID-19 disease.
All other previously vaccinated and unvaccinated individuals aged 6 months and older, who are not at increased risk for SARS-CoV-2 infection or severe COVID-19 disease, may also receive the a recently updated vaccine in the fall of 2024.
Read the National Advisory Committee on Immunization’s recommendations.
What if I miss my next dose?
If you miss your next dose or forget to go back to your vaccination provider at the scheduled time for your next dose, ask your vaccination provider/centre as soon as possible for advice.
Book your next dose here
Do all COVID-19 vaccines cover new variants?
Manufacturers and public health authorities continue to monitor emerging SARS-CoV-2 mutants (or “variants”), and new vaccines are continuously being developed.
Follow Public Health recommendations to make sure you stay up to date with your COVID-19 immunization.
You should continue to observe Public Health measures, even if you have been vaccinated.
Read the National Advisory Committee on Immunization’s recommendations.
Can children receive a primary series?
Yes. Children aged 6 months and older may receive a primary vaccination series. For more information on the right time for your child to get their vaccine, talk to your healthcare professional.
How many doses will I/my child receive?
Depending on the vaccine, you may need 1, 2, or 3 doses to complete the primary series.
COMIRNATY requires 1 dose for adults and children aged 5 years and up, and a maximum of 3 doses for children aged 6 months through 4 years.
While efforts should be made to vaccinate according to the recommended schedules, some provinces may provide alternative schedules.
It is very important that you return for your subsequent doses as recommended. Your risk of getting COVID-19 is further reduced if you receive all doses.
A third dose of COMIRNATY may be considered as part of the primary series in people 5 years and older who are immunocompromised, including those receiving immunosuppressant therapy, because they may have a diminished immune response to the vaccine.
About COVID-19
What is COVID-19?
COVID-19 infection is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV- 2). COVID-19 symptoms can vary from person to person and by age groups. The most common symptoms include : runny nose, sneezing, sore throat and headache. Less common symptoms include persistent cough, joint pain, chills, fever, dizziness, muscle pain, nausea, diarrhea, abdominal pain, hoarse voice and new loss of or altered sense of smell.
How is COVID-19 spread?
COVID -19 is spread through the air by droplets and very small particles that are created when an infected person breathes, coughs, sneezes, sings, shouts, or talks. These droplets and particles can be breathed in by other people or land on their eyes, noses, or mouth. In some circumstances, they may contaminate surfaces they touch.
Anyone infected with COVID-19 can spread the virus, and a person may be infectious for up to 2 to 3 days before showing any symptoms.
COVID-19 can spread from people to animals in some situations. Pet cats and dogs can sometimes become infected by people with COVID-19.
What happens when the virus mutates?
Viruses typically mutate, and mutations happen at different rates for different viruses. Virus mutations may affect how well a vaccine works against a virus. Several SARS-CoV-2 mutants (or “variants”) have emerged, and manufacturers and public health authorities continue to monitor the situation closely. It is important to stay up to date with the latest recommended additional doses and continue to observe public health measures even if you’ve been vaccinated.
Who is considered immunocompromised?
Immunocompromised individuals are those who have suppressed immune function due to a medical condition or medications. They tend to be at an increased risk for prolonged infection and serious complications from SARS-CoV-2 infection. Immunocompromised states include primary immune deficiency, solid organ or hematopoietic stem-cell transplant, HIV infection, chronic kidney disease on dialysis, or immunosuppressive therapy.
Who is at high risk of severe COVID-19?
Anyone can be infected with SARS-CoV-2 however, some populations are at a higher risk of prolonged infection and severe disease. Risk factors include advanced age, obesity, chronic kidney or lung disease, heart conditions, pregnancy, diabetes and other pre-existing medical conditions. NACI strongly recommends vaccination in these groups, which also include individuals in or from First Nations, Métis and Inuit communities, members of racialized and other equity-deserving communities and people who provide essential community services.
Find a list of underlying medical conditions associated with more severe COVID-19 disease here.
About COVID-19 vaccinations
Should I get vaccinated if I already wear a mask, practice physical distancing, and use good hygiene practices?
Yes. By getting vaccinated against COVID-19, you’re doing your part to help protect yourself against the disease.
Learn more
Should I, or can I, still get vaccinated if I’ve already been infected with COVID-19?
If you were previously infected with COVID-19, your healthcare professional will advise you on when you can receive the vaccine.
A dose of a latest formulation of COVID-19 vaccine may be received 3-6 months after infection. The minimum interval is 3 months from the last dose or infection. This minimum interval of 3 months will ensure that those who receive a spring 2024 dose will be eligible again for an updated fall 2024 dose when it becomes available.
If you were treated for COVID-19 with monoclonal antibodies or convalescent plasma, make sure you notify your healthcare professional as this may affect the timelines for your vaccination. If you are currently experiencing symptoms of COVID-19, talk with your healthcare professional about your symptoms getting a COVID-19 test, and potential vaccination.
Is it better to gain immunity from a natural COVID-19 infection rather than a COVID-19 vaccine?
No. Being infected with COVID-19 puts you at risk of developing symptoms, some of which can lead to hospitalization and long-term consequences. As for COVID-19 vaccines, side effects are usually mild or moderate and do not last long.
Can I still spread COVID-19 once I'm vaccinated?
COVID-19 vaccines have been shown to be effective in preventing the disease in individuals. Please continue to follow recommended Public Health measures even after you get vaccinated. Vaccination does not guarantee 100% protection for those who get immunized.
Can I stop using protective measures once vaccinated?
Continue to follow the recommendations of local Public Health officials to prevent the spread of COVID-19.
Can I receive other vaccinations at the same time as my COVID-19 vaccine?
For individuals 6 months of age and older, COVID-19 vaccines may be given on the same day, or at any time before or after other non-COVID vaccines.
How is mRNA technology different from other vaccines?
Other vaccines use weakened or inactivated bacteria and viruses or their parts to trigger an immune response inside our bodies. Instead, mRNA vaccines teach our cells how to make a protein that triggers our immune system to make antibodies and immune cells. These antibodies and immune cells help us fight the infection if the real virus enters our body in the future.
How is vaccine safety monitored in Canada?
Available vaccines are closely monitored by Health Canada. Health Canada continues the monitoring and assessment practices that were started during the COVID-19 pandemic, as well as continuing collaboration and information sharing within Canada and around the world.
Vaccine manufacturers such as Pfizer are also responsible for continuous monitoring of the safety of their product and reporting any side effects to Health Canada. This includes notifying Health Canada of any safety concern that was not observed during the clinical trials.
Companies may be asked to increase their monitoring and are encouraged to fast-track reporting of possible side effects associated with COVID-19 vaccines.
Health Canada has a goal to quickly respond to new information and communicate risks to healthcare professionals and the public.
About COVID-19
What is COVID-19?
COVID-19 is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID-19 symptoms can vary from person to person and by age groups. The most common symptoms include: a new or worsening cough, shortness of breath or difficulty breathing, temperature equal to or over 38°C, feeling feverish, chills, fatigue or weakness, muscle or body aches, new loss of smell or taste, headache, gastrointestinal symptoms (abdominal pain, diarrhea, vomiting), and feeling very unwell.
How is COVID-19 spread?
COVID-19 is spread mainly through close contact from person to person, especially people who are within 6 feet (about 2 metres) of one another. People who are infected but show no symptoms can also spread the virus to others. Infections of COVID-19 occur mainly through exposure to an infected person’s respiratory droplets (produced when someone coughs, sneezes, sings, or talks). In some cases, smaller respiratory droplets can remain suspended in the air and infect others who may be more than 6 feet from the infectious person, or even after that person has left the space. It is possible that a person could get COVID-19 by touching a surface or object that has the virus on it and then touching their own mouth, nose, or eyes.
Spread from touching surfaces is not thought to be a common way that COVID-19 spreads.
COVID-19 is rarely spread between people and animals.
Should I get vaccinated if I already wear a mask, practice physical distancing, and use good hygiene practices?
Yes. By getting vaccinated against COVID-19, you’re doing your part to help protect yourself against the disease.
Learn more
What happens when the virus mutates?
Viruses typically mutate, and mutations happen at different rates for different viruses. Virus mutations may affect how well a vaccine works against a virus.
There are several SARS-CoV-2 mutants, typically called "variants of concern" that have appeared, and manufacturers and regulators are monitoring the situation closely. You should continue to observe Public Health measures, even if vaccinated, as we learn more about these new variants and how effective the vaccines are against them.
COMIRNATY
Is COMIRNATY® the same as the Pfizer-BioNTech COVID-19 vaccine? 
Is COMIRNATY® the same as the Pfizer-BioNTech COVID-19 vaccine?
Yes. COMIRNATY is the official name of the Pfizer-BioNTech COVID-19 vaccine. As of September 16, 2021, the Pfizer-BioNTech COVID-19 vaccine is also referred to under the brand name COMIRNATY in Canada.
What side effects can I expect after vaccination with COMIRNATY?
The most common side effects (may affect more than 1 in 10 people) include: irritability (in children 6 months to 2 years), pain and/or swelling at the injection site, tiredness, headache, muscle pain, chills, joint pain, fever and diarrhea.
Learn more
How many people have been vaccinated with COMIRNATY?
COMIRNATY has been studied in over 22,000 individuals in clinical trials. In the real world, over 20 million Canadians have received both doses of COMIRNATY and over 10 million have received a third dose (as reported in August 2022).
Can children receive COMIRNARTY?
Yes. COMIRNATY is authorized for use in children aged 6 months and older, as a primary series and as a booster. Children over 5 years old should be given 2 primary doses. Children 6 months to <5 years old should be given 3 primary doses. For children aged 6 months to less than 12 years, each of these doses will be smaller than the doses given to people aged 12 years or older (0.2 mL instead of 0.3 mL). The total amount of vaccine for infants (6 months to <5 years) is 1/10 the adult dose, while the amount for children 5 to <12 years old is 1/3.
For more information, ask your healthcare professional where you receive your vaccine.
Can I receive a booster dose?
A booster dose may be given to people 16 years of age and older, at least 6 months after completion of the primary series.
The National Advisory Committee on Immunization (NACI) recommends a booster dose of an authorized COVID-19 vaccine should be offered 6 months after completion of a primary COVID-19 vaccine series to adults ≥12 years of age.
The use of COMIRNATY for a booster dose should be offered to individuals 18 to 29 years of age.
A booster dose of COMIRNATY may be given at least 6 months after completion of a primary series in individuals 5 years through ˂12 years of age.
NACI recommends that a booster dose of COMIRNATY (10 mcg) should be offered ≥6 months after completion of a primary COVID-19 vaccine series to children 5 to 11 years of age with an underlying medical condition and may be offered ≥6 months after completion of a primary COVID-19 vaccine series to all children 5 to 11 years of age who do not have underlying medical conditions.
How many doses will I receive if I am immunocompromised?
A third dose may be considered as part of the primary series in people 5 years and older who are immunocompromised, including those receiving immunosuppressant therapy, because they may have a diminished immune response to the vaccine.
Does the vaccine cover new variants?
There are several SARS-CoV-2 mutants, typically called "variants of concern", that have appeared, and manufacturers and regulators are monitoring the situation closely. New vaccines are being developed to target specific variants, like Omicron. Follow Public Health recommendations as these additional vaccines become available.
You should continue to observe Public Health measures, even if vaccinated, as we learn more about these new variants and how effective the vaccines are against them.
Should I or can I still get vaccinated if I’ve already been infected with COVID-19?
You can be vaccinated regardless of whether or not you have already had COVID-19. Even if you have had COVID-19, please continue to follow the recommendations of local Public Health officials.
If you were previously infected with COVID-19, your healthcare professional will advise you when you are able to receive the vaccine.
If you or your child have been infected with COVID-19 prior to completing the primary vaccination series, you should receive the vaccine 8 weeks after symptom onset or positive test (if asymptomatic).
Individuals ≥12 years old who were infected after their primary series (but before booster dose) should receive the vaccine 3 months after symptom onset or positive test (if asymptomatic), and at least 6 months after the second dose.
If you were treated for COVID-19 with monoclonal antibodies or convalescent plasma, make sure you notify your healthcare professional as this may affect the timelines for your vaccination. If you are currently experiencing symptoms of COVID-19, talk with your healthcare professional about your symptoms and getting a COVID-19 test, and potential vaccination.
Is it better to gain immunity from a natural COVID-19 infection rather than a COVID-19 vaccine?
No. Being infected with COVID-19 puts you at risk of developing symptoms, some of which can lead to hospitalization and long-term consequences.
As for COVID-19 vaccines, side effects are usually mild or moderate and do not last long.
Can I still spread disease once vaccinated?
COVID-19 vaccines have been demonstrated to be effective in preventing the disease in individuals, but it is currently unknown if or to what degree vaccination will be sufficient to prevent transmission. Please continue to follow recommended Public Health measures even after you get vaccinated.
Vaccination does not guarantee 100% protection for those who get immunized.
Can I stop using protective measures once vaccinated?
Continue to follow the recommendations of local Public Health officials to prevent the spread of COVID-19.
How is mRNA technology different from other vaccines?
Other vaccines use weakened or inactivated bacteria and viruses or their parts to trigger immune response inside our body. Instead, mRNA vaccines teach our cells how to make a protein that will trigger an immune response. Once triggered, our body then makes antibodies. These antibodies help us to fight the infection if the real virus does enter our body in the future.
How is vaccine safety monitored in Canada?
Available vaccines are closely monitored by Health Canada. During the COVID-19 pandemic, Health Canada has increased the monitoring and assessment practices concerning emerging safety issues, as well as increased collaboration and information sharing within Canada and around the world.
Vaccine manufacturers such as Pfizer are also responsible for continuous monitoring of the safety of their product and reporting any side effects to Health Canada. This includes notifying Health Canada of any safety concern that was not observed during the clinical trials. Companies may be asked to increase their monitoring and are encouraged to fast-track reporting of possible side effects associated with COVID-19 vaccines.
Health Canada has a goal to quickly respond to new information and communicate risks to healthcare professionals and the public.
Vaccination and Me
When and how do I book an appointment to get vaccinated?
Learn more about when and where to get vaccinated in your area.
Which vaccine will I get?
Your choice of vaccine against COVID-19 will be based on the one(s) distributed in your community and will depend on your local Public Health recommendations. The federal government has been working closely with provinces and territories on a plan to distribute vaccines.
All vaccines available in Canada have been shown to be effective against COVID-19.
Depending on the vaccine, you may need 1, 2 or 3 doses to complete the primary series. COMIRNATY requires 2 doses for adults and children aged 5 and up, and 3 doses for children 6 months to <5 years.
It is very important that you return for your subsequent dose of COMIRNATY, as recommended. Your risk of getting COVID-19 is further reduced if you receive all doses.
A third dose may be considered as part of the primary series in people 5 years and older, who are immunocompromised, including those receiving immunosuppressant therapy, because they may have a diminished immune response to the vaccine.
How many doses of the vaccine do I need?
The vaccine’s protection was established in clinical trials based on a two-dose schedule in individuals 5 years and older and it may not work as well if you do not receive both doses.
A booster dose may be given to people 16 years of age and older, at least 6 months after completion of the primary series.
The National Advisory Committee on Immunization (NACI) recommends a booster dose of an authorized COVID-19 vaccine should be offered 6 months after completion of a primary COVID-19 vaccine series to adults ≥12 years of age.
A booster dose of COMIRNATY may be given at least 6 months after completion of a primary series in individuals 5 years through ˂12 years of age.
NACI recommends that a booster dose of COMIRNATY (10 mcg) should be offered ≥6 months after completion of a primary COVID-19 vaccine series to children 5 to 11 years of age with an underlying medical condition and may be offered ≥6 months after completion of a primary COVID-19 vaccine series to all children 5 to 11 years of age who do not have underlying medical conditions.
When should I get my next dose?
While efforts should be made to vaccinate according to the recommended schedule, provinces may provide alternative schedules.
What if I miss my next dose?
If you miss your second dose or forget to go back to your vaccination provider at the scheduled time for your next dose, ask your vaccination provider/centre as soon as possible for advice.
It is very important that you return for your subsequent dose of COMIRNATY, as recommended. The vaccine may not work as well if you do not receive all doses.
When should I get my booster dose?
At least 6 months after completion of the primary series, a booster dose may be given to people 16 years of age and older.
The National Advisory Committee on Immunization (NACI) recommends a booster dose of an authorized COVID-19 vaccine should be offered 6 months after completion of a primary COVID-19 vaccine series to adults ≥12 years of age.
A booster dose COMIRNATY may be given at least 6 months after completion of a primary series in individuals 5 years through <12 years of age.
NACI recommends that a booster dose of COMIRNATY (10 mcg) should be offered ≥6 months after completion of a primary COVID-19 vaccine series to children 5 to 11 years of age with an underlying medical condition and may be offered ≥6 months after completion of a primary COVID-19 vaccine series to all children 5 to 11 years of age who do not have underlying medical conditions.
Can I receive other vaccinations at the same time as my COVID-19 vaccine?
The National Advisory Committee on Immunization (NACI) has updated its guidance on the use of other adult vaccines around the COVID-19 vaccines dosing timelines:
COVID-19 vaccines may be given on the same day, or at any time before or after other non-COVID vaccines.
At this time, NACI recommends that children 5 to under 12 years old receive COMIRNATY at least 14 days before or after another vaccine. There may be circumstances when a dose of a COVID-19 vaccine and another vaccine need to be given at the same time – a healthcare provider can help with this decision.
Learn more for adults here
Learn more for children here
How long does my protection against COVID-19 last?
Evidence indicates that the vaccines used in Canada are effective at preventing COVID-19. A booster dose following a primary series of mRNA vaccines is recommended. It is not yet known how long COVID-19 vaccines provide protection. More data is needed from ongoing and additional studies in the long-term to understand how long protection lasts after COVID-19 immunization.
Receiving all your recommended doses provides protection:
-this protection may decrease over time and isn't as effective for Omicron as it was with other variants.
“The development of COVID-19 vaccines was rushed.”
While moving at extraordinary speed, the development of COVID-19 vaccines maintained the highest quality of science and safety standards. All regulatory and operational steps that are taken for a trial under regular circumstances were completed for the COVID-19 vaccine clinical development process. Robust safety data were generated from the clinical trial that enrolled approximately 55,000 participants and Pfizer continues to monitor vaccine safety as the vaccine is introduced in the population .
“mRNA vaccines will alter my DNA.”
- No, mRNA vaccines will
not alter your DNA. Here are 3 reasons why:
- 1) mRNA cannot enter your cells’ nucleus – this is where your DNA exists.
- 2) mRNA cannot be transformed into DNA, unless it is exposed to a special protein that only exists
in certain viruses – the COVID-19 virus does not contain these special proteins. -
3) mRNA is not very stable and can only remain active in human cells for hours.
“Vaccines often cause serious side effects.”
Most side effects are usually
minor and temporary
and
serious side effects are uncommon.
Vaccines are rigorously tested before coming to market and scientists are constantly monitoring information for any safety signals. There is a rare chance that an individual may experience a severe allergic reaction to the vaccination, so it is important to tell your vaccination provider about any allergies you may have.
“Vaccines won’t protect me against COVID-19.”
Studies have shown that COVID-19 vaccines are effective at helping protect you against COVID-19.
While COVID-19 vaccines have been demonstrated to be effective in helping to prevent the disease in individuals – please continue to follow recommended Public Health measures even after you get vaccinated.