Questions & Answers about COVID-19 Vaccination

EVERYTHING YOU NEED TO KNOW ABOUT THE PRIMARY SERIES OF COVID-19 VACCINES

WHY IS THE PRIMARY VACCINE SERIES IMPORTANT?

The primary vaccine series refers to the number of doses initially received to allow the body to develop an immune response and provide initial protection.

The number of doses included in this primary vaccine series varies depending on the vaccine and on the person’s health. For example, people who are immunocompromised may require additional doses of vaccine to achieve a sufficient immune response.

Ask a health professional or consult your provincial government’s COVID-19 website to learn more about the primary vaccine series.

HOW LONG DOES IT TAKE FOR THE VACCINES TO PROVIDE PROTECTION?

The effect of vaccination is not immediate. Your immune system needs a few days or even a few weeks after the vaccine is injected to mount a full antibody response.

EVERYTHING YOU NEED TO KNOW ABOUT BOOSTER DOSES

WHY ARE BOOSTER DOSES IMPORTANT?

Studies have shown that after the primary series of COVID-19 vaccines, your level of antibodies decreases over time. Booster shots are therefore recommended to bring those antibodies back up to a level high enough to provide sufficient protection against the virus.

Ask a health professional about eligibility criteria and recommended intervals between the primary series and the first booster shot or between two booster shots.

CAN I GET A DIFFERENT VACCINE FROM THE ONE I GOT BEFORE?

Yes. It is possible to receive a different vaccine from the one you originally received. It can be a vaccine made using either the same or a different technology as your previous vaccine.

To learn more about available vaccines, consult a health professional.

What are COVID-19 variants?

The viruses belonging to the coronavirus family mutate constantly when they multiply, creating what are known as “variants.” Often these mutations have no consequences, however, sometimes they can make the virus easier to transmit or more likely to cause a more serious infection.

IS IT STILL WORTH GETTING VACCINATED EVEN THOUGH VARIANTS KEEP EMERGING?

YES. Vaccination is still the most effective way to reduce the risk of falling seriously ill, requiring hospitalization, or dying in the event you contract COVID-19, especially if you have a weakened immune system or a chronic health problem.

New versions of the COVID-19 vaccines are currently being developed to provide more specific protection against the variants of the disease.

DO COVID-19 VACCINES CAUSE SIDE EFFECTS?

YES, like with all vaccines, side effects are possible. However, most reactions are mild and short term.

The COVID-19 vaccines approved by Health Canada are safe. The most common side effects include

• Pain, soreness, or redness at the injection site
• Fever or chills
• Tiredness
• Headache
• Muscle or joint pain

If these side effects do occur, they will usually only last several hours or a few days at most. If symptoms worsen or persist, contact a healthcare professional.

What to do right after receiving the vaccine:

• Wait onsite for at least 15 minutes after receiving the vaccine, to be sure that you are feeling well and do not experience any immediate reaction.
• Inform the healthcare provider if you feel unwell while you are waiting.
• Use an alcohol-based sanitizer to clean your hands before leaving the vaccination centre.
• Do not operate a vehicle or any other form of transportation after receiving the vaccine if you feel unwell.

DO COVID-19 VACCINES CAUSE MORE SERIOUS ALLERGIC REACTIONS THAN OTHER AVAILABLE VACCINES?

NO. Over 85 million doses have been administered in Canada, and the risk of allergic reaction is very low.

The risk of severe allergic reaction with COVID-19 vaccines does not appear to be any higher than for other types of common vaccines.

If you suffer from severe allergies, talk to your pharmacist. They can provide you with all the details on the various vaccines available and how you can get vaccinated safely.

VACCINATION AMONG AT-RISK PEOPLE

SHOULD I GET VACCINATED EVEN IF I’M IMMUNOCOMPROMISED?

YES. Given the serious health consequences of COVID-19, health authorities recommend that people with weakened immune systems—whether due to a disease or medical treatment—get vaccinated.

Since these people often fail to develop as strong an immune response as healthy people, in most cases they will require an additional dose in the primary series, followed by the recommended booster shots.

Some people with severely compromised immune systems may also be eligible for preventive monoclonal antibody treatment, in addition to vaccination.

For more on vaccination and preventive treatments, consult a health professional.

SHOULD I GET VACCINATED IF I’M PREGNANT OR BREASTFEEDING?

YES. The risk of COVID-19–related complications is higher in pregnant women, especially those with chronic health problems. Current data also shows that vaccination is safe through all stages of pregnancy and during breastfeeding.

The National Advisory Committee on Immunization (NACI) recommends a complete series of an mRNA vaccine in women who are pregnant or breastfeeding, as well as booster shots once they are eligible.

IS VACCINATION RECOMMENDED FOR CHILDREN?

While kids who are healthy generally don’t get very sick when they contract COVID-19, there is still a risk they will experience complications. Just like for adults, that risk is higher among children with chronic health problems.

The COVID-19 vaccine can be administered before, after, or at the same time as other vaccines included in your child’s vaccination schedule.

For more about vaccination for children, talk to a health professional.

Vaccine development

CAN I TRUST THE COVID-19 VACCINE EVEN THOUGH IT WAS BROUGHT TO MARKET SO FAST?

YES. There are many reasons why COVID-19 vaccines were developed so quickly, but that doesn’t mean they were rushed:

• The Pfizer/BioNTech and Moderna COVID-19 vaccines were created using a method that had been under development for years. As a result, the two companies were able to begin developing the vaccine early in the pandemic.
• Numerous scientific communities shared information about the genetic code of the virus that causes COVID-19, which allowed scientists to start working to develop a vaccine right away.
• While vaccine developers didn’t skip any steps in the testing process, since some of their steps overlapped, they were able to gather evidence faster.
• Vaccine development benefited from plenty of resources, with some governments investing in research or paying for vaccines in advance.
• Companies began making vaccines early in the process, to ensure they would be available as soon as they received authorization from the health authorities.

CAN THE mRNA TECHNOLOGY USED TO MAKE THE COVID-19 VACCINE ENTER MY CELLS AND ALTER MY DNA?

NO. The mRNA technology used to make certain COVID-19 vaccines has been in existence for nearly two decades. This technology was developed specifically to help respond quickly in the event of a pandemic.

Your DNA is stored in the part of your body’s cells called the “nucleus.” While the messenger RNA (mRNA) contained in the vaccine enters into your cells, it does not go all the way to the nucleus. What’s more, it breaks down in a few hours, after triggering production of the proteins that will allow your immune system to recognize and fight the virus.

Other FAQ

CAN COVID-19 VACCINES GIVE YOU COVID-19?

NO. None of the vaccines available in Canada can transmit COVID-19.

The vaccines authorized in Canada work by helping your body develop specific antibodies to fight the virus. These vaccines do not contain the SARS-CoV-2 virus, and therefore cannot cause the infection.

CAN THE COVID-19 VACCINE TREAT COVID-19?

NO. The vaccine does not treat COVID-19; it helps prevent complications caused by the infection.

There are now COVID-19 treatments available for non-hospitalized patients. They are offered to people who are at very high risk of complications if they contract the disease. For information on eligibility for these treatments, consult a health professional.

SHOULD I GET VACCINATED IF I’VE ALREADY HAD COVID-19?

YES, given the emergence of new variants, it is possible to get COVID-19 more than once.

Getting vaccinated after you have been previously infected with COVID-19 helps improve your immune response and may provide better and longer lasting protection than your body’s natural protection.

It is recommended you wait several months after having the infection before you get vaccinated. Interval times may vary depending on your body’s ability to build a strong immune response to the virus or the vaccine.

Your healthcare provider can recommend the best time to get vaccinated after you’ve had COVID-19, based on your health.

Still got questions about COVID-19 vaccination? Talk to a health professional or consult your provincial government’s COVID-19 website.