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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). COVID-19 is a new strain of coronavirus that has caused a worldwide pandemic. 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 in Canada.

mRNA vaccines
The Pfizer-BioNTech and Moderna vaccines are mRNA vaccines.

mRNA vaccines have messenger RNA (mRNA) that teaches your cells to make a protein (called a spike protein). This is a spike protein like the one that’s on the surface of the virus that causes COVID-19. Because the protein isn’t normally found on your cells, it triggers your immune system to make antibodies against it. So if you come in contact with the real COVID-19 virus, these antibodies will be ready to protect you and fight the virus. 

Learn more about COVID-19 mRNA vaccines.

Viral vector-based vaccines
The AstraZeneca/COVISHIELD and Janssen vaccines are viral vector-based vaccines.

Viral vector-based vaccines use a harmless virus (that isn’t COVID-19) to carry information about the virus that causes COVID-19. This virus won’t give you COVID-19. It shows your cells how to make a spike protein, like the one that’s on the surface of the COVID-19 virus. This protein triggers your immune system to make antibodies against it. If you come in contact with the real COVID-19 virus, these antibodies will be ready to protect you and fight the virus.  

Who should get a COVID-19 vaccine?

You should get a COVID-19 vaccine if you’re age 16 years and older. COVID-19 vaccines are free.

You’re able to get the vaccine when it’s your turn. Go to​ to find out what type of COVID-19 vaccine you can get and when you can get it. Please check this page often as it’s updated regularly. 

Everyone is at risk of COVID-19. The vaccine is very important for people who are more likely to be in contact with the virus because of where they work or live. This includes healthcare providers and people who live in a care facility, such as a nursing home.

It’s also important for people who have a high risk of complications from COVID-19 to get the vaccine. This includes people who:
  • have health problems, such as heart, lung, kidney, or liver problems, high blood pressure, or diabetes
  • have a lot of extra weight
  • are over the age of 60 years

If you’re able to get the AstraZeneca/COVISHIELD vaccine, you can choose to have this vaccine now or wait for an mRNA COVID-19 vaccine. 

Once you get your first dose of a COVID-19 vaccine, you won’t be able to switch to another type of COVID-19 vaccine to complete your immunization.

How many doses do I need?

For the COVID-19 vaccines approved in Canada, you need 1 or 2 doses. The number of doses depends on the vaccine you get. If you get a vaccine that needs 2 doses, your healthcare provider will let you know when you should get your second dose.

Visit for more information.

How well do the COVID-19 vaccines work?

If you’re healthy and get all the doses you need, the protection for COVID-19 is about:
  • ​95% for an mRNA vaccine
  • 60% to 70% for a viral vector-based vaccine
Any COVID-19 vaccine you get will lower your risk of getting seriously ill from COVID-19. It’ll also lower your risk of needing to be in the hospital.

At this time, there’s not enough information to know how long protection lasts or if you’ll need booster doses.

It’s still important to practice the recommended public health measures to prevent the spread of COVID-19, even if you’ve had the vaccine. This includes:
  • following guidelines of when to wear a mask or other equipment that helps protect you
  • washing your hands often
  • staying 2 metres away from others
  • staying home when you’re sick (this means isolating)
  • staying home for 14 days after having close contact with someone who has COVID-19 or returning from travel outside of Canada (this means quarantining)

Visit for more information, including information about isolation and quarantine​.

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 the COVID-19 vaccine?

There can be side effects from the COVID-19 vaccine, 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 or unwell
  • a headache
  • a fever or chills
  • body aches or sore joints
  • feeling sick to your stomach (nausea), vomiting (throwing up), or loose stool (diarrhea)
  • swollen lymph nodes

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/COVISHEILD 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 is about 1 case in 100,000 to 250,000 doses of the AstraZeneca/COVISHIELD vaccine.

COVID-19 continues to spread at a high rate in Alberta. Your risk of serious illness from COVID-19 is much higher than it is for developing a rare event after getting the vaccine.
Go to COVID-19 Vaccine Frequently Asked Questions​ for more information.​

If you have any of the following symptoms, get medical help right away:
  • shortness of breath
  • chest pain
  • leg swelling
  • stomach pain that doesn’t go away
  • a severe headache that doesn’t go away
  • blurry vision
  • bruising (other than where you had the needle)
  • red or purple spots anywhere on your body
  • bleeding (more easily than normal)​​

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?
Wait at least 28 days after you have a dose of the COVID-19 vaccine before you get another vaccine.

If you’ve had another vaccine, wait 14 days before you get a COVID-19 vaccine.​

Who should not have a COVID-19 vaccine?

You may not be able to have the 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 16 years
  • have had another vaccine in the last 2 weeks

Check with your doctor or a public health nurse before you get the 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)
  • are pregnant, breastfeeding, or plan to get pregnant in the next 28 days​

There isn’t enough evidence to know if the vaccine is safe and protects against COVID-19 in these groups.

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

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 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 door knob) 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: April 22, 2021

Author: Provincial Immunization Program, Alberta Health Services