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COVID-19 vaccines


​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​Immunization protects you from disease.
​​Get protected, get immunized.

  • Vaccines make your immune system stronger. They build antibodies to help prevent diseases.
  • Immunization is safe. It's much safer to get immunized than to get this disease.​

What are COVID-19 vaccines?

COVID-19 vaccines protect against the SARS-CoV-2 virus (also known as COVID-19). The virus causes an infection in the lungs and airways and is a type of respiratory illness. Go to to learn more about COVID-19. 

There are 2 types of COVID-19 vaccines approved for use in Canada:
  • mRNA vaccines: The Pfizer-BioNTech (Comirnaty) and Moderna (SpikeVax) vaccines are mRNA vaccines. ​
  • Viral vector-based vaccines: The AstraZeneca (Vaxzevria)/ COVISHIELD vaccine is a viral vector-based vaccine. ​

Who should get a COVID-19 vaccine?

​You should get a COVID-19 vaccine if you’re age 12 years or older. Everyone is at risk of COVID-19. COVID-19 vaccines are free.

If your child is getting a COVID-19 vaccine
Children under age 18 years need a parent or guardian to give consent for their immunization. If a parent or guardian can’t attend the appointment, they can give their written consent. Please complete the consent form found at In some cases, children under age 18 years may be able to give their own consent.

Can I get a COVID-19 vaccine if I'm pregnant or breastfeeding?

​Yes, you can get a COVID-19 vaccine if you’re pregnant or breastfeeding. When you’re pregnant, you have a higher risk of getting very sick from COVID-19. Getting a COVID-19 vaccine during pregnancy lowers your risk of getting seriously ill from COVID-19.

It’s best to get an mRNA COVID-19 vaccine if you’re pregnant. Research to date shows that it’s the safest type of COVID-19 vaccine to get during pregnancy.

​If you’re pregnant or breastfeeding and have questions about getting a COVID-19 vaccine, talk to your healthcare provider.

How many doses do I need?

Moderna, Pfizer-BioNTech, and AstraZeneca/COVISHIELD vaccines require at least 2 doses. 

You may need additional doses of COVID-19 vaccine to give you more protection if you have a high risk of severe disease due to:​

  • your age
  • a health problem that weakens your immune system, for example you’ve had or will have an organ or stem cell transplant, you have kidney disease and need dialysis, or you have acquired immunodeficienty syndrome (AIDS)
  • certain medicines that weaken your immune system
  • living in a specific type of seniors congregate living facility, such as long-term care

If you’re travelling outside of Canada, you may be able to get additional doses. This only applies if your destination requires you to have a certain COVID-19 vaccine series.

If you are getting additional doses, your healthcare provider will let you know when you should have them. 

Visit for more information and to find out if you can get additional doses.

If you get additional doses, this is “off-label” use of the vaccine. This means the vaccine is not licensed for additional doses, but vaccine experts support this in certain situations. If you have questions about getting additional doses, talk to your healthcare provider.

How well do COVID-19 vaccines work?

If you’re healthy and get all the doses you need, COVID-19 vaccines give you very good protection against COVID-19. The mRNA vaccines are somewhat more effective than the viral vector-based vaccines.

You need both doses for the greatest protection. All COVID-19 vaccines work very well to lower your risk of getting seriously ill from COVID-19. They also lower your risk of needing to be in the hospital.

​It’s still important to follow the recommended public health measures to prevent the spread of COVID-19, even if you’ve had a COVID-19 vaccine. Please visit ​ for the most up-to-date recommendations.

​Which COVID-19 vaccine will I get?

​​​You will get an mRNA vaccine unless you are unable to receive or do not want an mRNA vaccine.

I got an mRNA vaccine as my first dose. Can I get a different mRNA vaccine for my second dose?

Usually you get the same vaccine for all your dose​s. But you can get a different mRNA vaccine for your second dose if your first-dose vaccine isn’t available or you prefer a different available mRNA vaccine. Both Pfizer-BioNTech and Moderna COVID-19 vaccines work in the same way.

Whichever vaccine you get for your second dose completes your immunization series and protects you against COVID-19.

Go to​ for more information.

What if I got the AstraZeneca/COVISHIELD vaccine as my first dose?

If you got the AstraZeneca/COVISHIELD vaccine for your first dose, you can choose the AstraZeneca/COVISHIELD vaccine or an mRNA vaccine for your second dose.

The AstraZeneca/COVISHIELD vaccine is a safe vaccine that works well to protect you against COVID-19. But some people may choose an mRNA vaccine to complete their COVID-19 immunization.

No matter which vaccine you choose, the second dose offers protection against COVID-19 and will complete your 2-dose series.

Go to​ for more information about getting an mRNA vaccine after an AstraZeneca/COVISHIELD vaccine.

If I need additional doses, what vaccine will I get?

You will get an mRNA vaccine for any additional doses. If you are unable to receive an mRNA vaccine, your healthcare provider will let you know which vaccine you can get.

Where can I get a COVID-19 vaccine?

Go to to find out where and when you can get a COVID-19 vaccine.

Are there side effects from COVID-19 vaccines?

There can be side effects from COVID-19 vaccines, but they tend to be mild and go away in a few days. Side effects may include:

  • redness, warmth, swelling, bruising, itching, or feeling sore where you had the needle
  • feeling tired, unwell, or have a headache
  • a fever or chills
  • body aches, sore joints, or pain in your legs and arms
  • feeling sick to your stomach (nausea), vomiting (throwing up), or loose stool (diarrhea)
  • swollen lymph nodes
  • a sore throat, cough, or runny nose
  • a reduced sense of touch or a feeling of numbness
  • feeling dizzy

You may be more likely to have these side effects if you have another vaccine at the same time as a COVID-19 vaccine.

Current information shows that the risk of side effects after additional doses of COVID-19 vaccine is similar to the risk after the first or second dose. Research continues to find out more about the risk of side effects after additional doses of COVID-19 vaccine.​

It’s important to stay at the clinic for 15 minutes after your vaccine. Some people may have a rare but serious allergic reaction called anaphylaxis. If anaphylaxis happens, you’ll get medicine to treat the symptoms.

It’s rare to have a serious side effect. Call Health Link at 811 to report any serious or unusual side effects.

Rare events after getting the AstraZeneca/COVISHIELD vaccine
There have been very rare reports of blood clots, low levels of platelets (these help your blood to ​clot), and bleeding after getting the AstraZeneca/COVISHIELD vaccine. 

These events happened 4 to 28 days after getting the vaccine. The risk of these events after getting the AstraZeneca/COVISHIELD vaccine​ is about:
  • 1 in 55,000 after the first dose
  • 1 in 600,000 after the second dose

Research is still ongoing to find out more about the risk of these events after getting the AstraZeneca/COVISHIELD vaccine.​

​If you have any of the following symptoms within 42 days of being immunized, get medical help right away:

  • trouble talking or moving a part of your body
  • shortness of breath
  • chest pain
  • severe swelling, pain, or a colour change in your arm or leg​
  • stomach pain that doesn’t go away
  • a severe headache that doesn’t go away
  • blurry vision

There have also been very rare reports of capillary leak syndrome (CLS) within the first few days after getting the AstraZeneca/COVISHIELD vaccine. In some reported cases, the person had a history of CLS. CLS is a serious condition that causes fluid to leak from the small blood vessels (capillaries). This causes sudden swelling of the arms and legs, sudden weight gain, and low blood pressure causing you to feel faint. CLS can be fatal. Get medical help right away if you have any of these symptoms.

Research is still ongoing to find out more about the risk of CLS after getting AstraZeneca/COVISHIELD vaccine. 

Rare events after getting either the Pfizer-BioNTech or the Moderna vaccine
There have been very rare reports of myocarditis (inflammation of the heart muscle) and pericarditis (inflammation of the lining around the heart) within 7 days of getting either the Pfizer-BioNTech or the Moderna vaccine. The inflammation can cause shortness of breath, chest pain or pressure, or a very fast or abnormal heart rate. Get medical help right away if you have any of these symptoms.

These rare events were reported mostly after the second dose and in young adults and adolescents. Most cases were mild and got better with treatment. The Moderna vaccine may have a higher risk of these events than the Pfizer-BioNTech vaccine. Because the Moderna vaccine was only recently approved for use in 12- to 17-year-olds, there is more to learn about the risks of these rare events for this age group after getting that vaccine. 

Research is still happening to find out more about the risk of these events from mRNA COVID-19 vaccines.

Talk to your healthcare provider if you've ever had myocarditis or pericarditis and have questions about getting a COVID-19 vaccine. ​At this time, there's not enough information to know if there is a higher risk of these events in these groups.

Your risk of serious illness from COVID-19 is much higher than it is for developing a rare event after getting this vaccine.

Go to COVID-19 Vaccine Frequently Asked Questions​ for more information.​

How can I manage side effects?
To help with soreness and swelling, put a cool, wet cloth over the area where you had the needle. 

There is medicine to help with a fever or pain. Check with your doctor or pharmacist if you’re not sure what medicine or dose to take. Follow the directions on the package. Children under the age of 18 years should not take aspirin because it can cause serious health problems.

Some people with health problems, such as a weak immune system, must call their doctor if they get a fever. If you’ve been told to do this, call your doctor even if you think the fever is from the vaccine.​

What if I had or am getting another type of vaccine?​

You can get any vaccine at the same time as, any time before, or any time after a COVID-19 vaccine. 

Who should not get the COVID-19 vaccine?

You may not be able to get​ a COVID-19 vaccine if you:

  • have an allergy to any part of the vaccine
  • had a severe (serious) or unusual side effect after this vaccine or one like it
  • are under age 11 years

Check with your doctor or a public health nurse before you get a COVID-19 ​vaccine.

Be sure to talk to your doctor before you get a COVID-19 vaccine if you:

  • have a weak immune system (because of a medicine you take or a health problem)
  • have an autoimmune disorder (like rheumatoid arthritis or lupus)
  • have had a stem cell or organ transplant
  • have a history of capillary leak syndrome (CLS)
  • have a history of myocarditis or pericarditis after receiving a dose of COVID-19 vaccine

Always tell your healthcare provider if you have allergies or if you've had a side effect from a vaccine in the past.

Facts about COVID-19

What is COVID-19?
COVID-19 is a new strain of coronavirus that’s caused a worldwide pandemic. The virus causes an infection in the lungs and airways and is a type of respiratory illness. Symptoms may include:

  • a fever
  • a cough
  • shortness of breath or trouble breathing
  • a sore throat
  • a runny or stuffy nose
  • loss of sense of smell or taste

Most people have only mild symptoms or no symptoms at all. But if you’re an older adult or have other health problems, you can get very sick and may need care in a hospital. In serious cases, COVID-19 can cause a type of lung infection called pneumonia. Pneumonia makes it hard to breathe without help and can even lead to death.​

Go to COVID symptoms​ for a list of all symptoms that may be related to COVID-19.

How does it spread?
COVID-19 spreads:

  • when an infected person sneezes, coughs, or talks
  • if you breathe in the virus
  • if you touch something that has the virus on it (like hands or a doorknob) then touch your eyes, mouth, or nose

It’s important to know that you and others can spread COVID-19 before symptoms start.

Go to to find out more.

How can I prevent COVID-19 from spreading?
To prevent COVID-19 from spreading:

  • get immunized
  • wash your hands with warm water and soap or use an alcohol-based hand sanitizer often
  • don’t touch your face, nose, or mouth with unwashed hands
  • cover your cough or sneeze into your arm or a tissue, not your hand
  • stay home when you’re sick
  • avoid close contact with people who are sick

If you think you’ve had contact with COVID-19 or have symptoms, take the COVID-19 Self-Assessment at

More information

Current as of: October 6, 2021

Author: Provincial Immunization Program, Alberta Health Services