There are eight vaccines approved in Canada for COVID-19:

• The Pfizer-BioNTech Comirnaty COVID-19 vaccine was approved by Health Canada on December 9, 2020.
• The Moderna Spikevax COVID-19 vaccine was approved by Health Canada on December 23, 2020.
• The AstraZeneca Vaxzevria and COVISHIELD vaccines were approved by Health Canada on February 26, 2021.
• The Janssen vaccine was approved by Health Canada on March 5, 2021.
• The Novavax Nuvaxovid vaccine was approved by Health Canada on February 17, 2022.
• The Medicago Covifenz vaccine was approved by Health Canada on February 24, 2022.
• The Moderna Spikevax bivalent COVID-19 vaccine was approved by Health Canada on September 1, 2022.
• The Pfizer-BioNTech Comirnaty COVID-19 bivalent vaccine was approved by Health Canada on October 7, 2022.

For information on COVID-19 vaccines, please see the Government of Canada’s website.

1. How do the Pfizer-BioNTech Comirnaty and Moderna Spikevax COVID-19 vaccines work?

This vaccine tells your body’s cells to make “spike proteins.” The spike proteins are specific to the virus that causes COVID-19. Your immune system will respond to the spike proteins by making antibodies that will fight off infection. Your new antibodies will break down the spike proteins and get rid of them. These new antibodies will protect you from illness if you are exposed to the COVID-19 virus. The vaccine does not contain the virus and so it cannot give you COVID-19.

The Pfizer-BioNtech Comirnaty and Moderna Spikevax vaccines have been tested in large clinical trials to ensure they meet safety standards, and have been licensed and approved by Health Canada

2. How do the AstraZeneca Vaxzevria, COVISHIELD and Janssen COVID-19 vaccines work?

This vaccine uses a harmless virus as a delivery system. In this case, it is the adenovirus, which is one of the viruses that can cause the common cold. Once injected into your body, the virus makes “spike proteins.” The spike proteins are specific to the virus that causes COVID-19. Your immune system will respond to the spike proteins by making antibodies that will fight off infection. Your new antibodies will break down the spike proteins and get rid of them. These new antibodies will protect you from illness if you are exposed to the COVID-19 virus. The vaccine does not contain the virus that causes COVID-19, so it cannot give you COVID-19.

The AstraZeneca Vaxzevria, COVISHIELD and Janssen vaccines have been tested in large clinical trials to ensure it has met safety standards, and has been licensed and approved by Health Canada.

3. How does the Novavax Nuvaxovid vaccine work?

The Novavax Nuvaxovid vaccine is the first recombinant protein subunit COVID-19 vaccine authorized for use in Canada. The vaccine contains the “spike protein” and an adjuvant. The spike proteins are specific to the virus that causes COVID-19. An adjuvant is an ingredient added to boost a person’s immune response. Your immune system will respond to the spike proteins by making antibodies that will fight off infection. Your new antibodies will break down the spike proteins and get rid of them. These new antibodies will protect you from illness if you are exposed to the COVID-19 virus. The vaccine does not contain the virus and so it cannot give you COVID-19.

The Novavax Nuvaxovid vaccine has been tested in large clinical trials to ensure it has met safety standards, and has been licensed and approved by Health Canada.

4. How does the Medicago Covifenz vaccine work?

The Medicago Covifenz vaccine is the first plant based virus-like particle (VLP) vaccine authorized for use in Canada. The plants used in the development of this vaccine produce Virus-Like Particles, or VLPs, in high volume. The VLPs in Covifenz look like the virus that causes COVID-19 to your immune system. Your immune system will respond to the VLPs by making antibodies that will fight off infection. Your new antibodies will break down the VLPs and get rid of them. These new antibodies will protect you from illness if you are exposed to the COVID-19 virus.  The vaccine does not contain the virus and so it cannot give you COVID-19.

The Medicago Covifenz vaccine has been tested in large clinical trials to ensure it has met safety standards, and has been licensed and approved by Health Canada.

5. How many doses of the vaccine are required?

The Pfizer-BioNTech Comirnaty, Moderna Spikevax, COVISHIELD and AstraZeneca Vaxzevria, Novavax Nuvaxovid and Medicago Covifenz vaccines consist of two doses given up to four months apart. It is very important to get both doses of the vaccine to complete your primary series. The Janssen vaccine consists of a single dose. Additional doses may be recommended for some age groups and special populations. Visit the Get the Shot page for more information about vaccine doses and eligibility.

6. What are the side effects of the vaccine?

Like any medication or supplement (including vitamins), vaccines can cause side effects and reactions.

After being vaccinated, it is common to have mild and harmless side effects. These can last a few hours or days after vaccination. Common side effects include:

Pfizer-BioNTech Comirnaty	Moderna Spikevax	Moderna Spikevax Bivalent	AstraZeneca Vaxzevria COVISHIELD	Janssen	Medicago Covifenz	Novavax Nuvaxovid
pain at injection site tiredness headache muscle pain chills joint pain fever enlarged lymph nodes rare reports of myocarditis or pericarditis	pain at injection site tiredness headache muscle ache and stiffness chills joint pain fever enlarged lymph nodes swelling or redness at the injection site nausea and/or vomiting rare reports of myocarditis or pericarditis	pain at the injection site tiredness headache muscle ache and stiffness chills fever swelling or redness at the injection site nausea and/or vomiting enlarged lymph nodes hypoaesthesia (decreased sense of touch or sensation, numbness) or paraesthesia (tingling, itching or pricking sensation) dizziness	pain at injection site generally feeling unwell tiredness headache joint pain or muscle ache chills/feeling feverish fever nausea vomiting or diarrhea rare risk of blood clots	pain at injection site tiredness headache muscle aches nausea fever redness/swelling at injection site chills joint pain	fatigue headache muscle pain	fatigue headache muscle pain

If you experience any unusual side effects after receiving the vaccine it is important to contact your health care provider or local public health office.

7. Who should not receive the vaccine?

You should not receive a COVID-19 vaccine if you have:

• a history of anaphylaxis after previous administration of any COVID-19 vaccine
• an immediate or anaphylactic hypersensitivity to any component of the vaccine. To view components in each COVID-19 vaccine, refer to the product monographs:
  • Moderna Spikevax
  • AstraZeneca Vaxzevria
  • COVISHIELD
  • Pfizer-BioNTech Comirnaty
  • Janssen
  • Novavax Nuvaxovid
  • Medicago Covifenz
  • Moderna Spikevax Bivalent

If you have a fever or you are sick with COVID-19 symptoms, you need to delay your vaccination.

If you have had a recent COVID-19 infection, please see the next question for guidance on the timing of your vaccine.

8. Can I get a COVID-19 vaccine if I had COVID-19?

It is possible that people will get COVID-19 before getting their COVID-19 vaccine. At the very least, people need to wait until they have fully recovered and completed their isolation period before getting their next dose.

Public health recommends waiting 3 months after a COVID-19 infection to receive a COVID-19 vaccine provided it has been 20 weeks since your last dose.

Recommendations may be different if you are moderately to severely immunocompromised. Please speak to your health care provider to get the best advice on when to get your next vaccine dose after a COVID-19 infection.

For more information on NACI’s recommendation on interval between infection and getting your next COVID-19 vaccine dose, please visit: COVID-19 vaccine: Canadian Immunization Guide – Canada.ca.

9. Should I talk to my health care provider before getting the vaccine?

People who are pregnant, breastfeeding or planning to become pregnant may consult with their health care provider to discuss any questions they may have about the vaccine. If you are immunocompromised, have an autoimmune disorder, a bleeding disorder, use blood thinner medication, or have any other underlying medical condition you may also consult with your health care provider before getting vaccinated.

10. When should I return for my second dose?

Visit the Get the Shot page for timing of primary series and booster doses.

11. What vaccine will I receive for my next dose?

Visit the Get the Shot page for timing of primary series and booster doses

12. I am moderately to severely immunocompromised, how many doses of vaccine should I receive?

Visit the Get the Shot page for timing of primary series and booster doses.

13. I am moderately to severely immunocompromised, can I receive a booster doses?

Visit the Get the Shot page to determine who is currently eligible to receive COVID-19 booster doses.

14. Am I eligible for a COVID-19 booster doses?

Visit the Get the Shot page to determine who is currently eligible to receive COVID-19 booster doses.

15. Which vaccine will I receive as a COVID-19 booster dose?

You can receive either Moderna Spikevax or Pfizer Comirnaty as a booster dose. If you are 18 years and older and unable or choose not to receive an mRNA vaccine as your booster dose, a recombinant protein subunit (Novavax Nuvaxovid) vaccine may be offered as a booster dose. You may be eligible for a Bivalent COVID-19 booster dose. Visit the Get the Shot page to determine who is currently eligible

16. My first dose of COVID-19 vaccine was AstraZeneca Vaxzevria/COVISHIELD, if I receive an mRNA dose now, will I need one dose or two?

You will only need to have one dose of mRNA vaccine following a dose of AstraZeneca Vaxzevria/COVISHEILD.

17. Who should receive the Novavax vaccine, Nuvaxovid?

Nuvaxovid vaccine may be offered to individuals 18 years of age without contraindications to the vaccine who are unable/unwilling to receive an mRNA vaccine.