COVID-19 - Get vaccinated and stay up to date, and find public health advice for residents.

Frequently Asked Questions about the COVID-19 Vaccine

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Vaccine safety

We know you want to be sure that COVID-19 vaccines are safe. Read the frequently asked questions and watch Dr. Hirji, (Acting Medical Officer of Health for Niagara Region) answer questions about vaccine safety.

  • How do I know that I won't get COVID-19 from the vaccine?

    There is no COVID-19 virus in the vaccine. The vaccines teach your immune system how to recognize and fight the virus that causes COVID-19.

    Some people may develop mild side effects such as fever. These symptoms typically mean the vaccine is working to produce protection. It usually takes the body a few weeks to build immunity after receiving a vaccine.

    You can become infected with the virus before or right after getting the vaccine. This happens because the vaccine has not had enough time to provide protection in your body.

  • What do I need to know about the long-term safety of mRNA vaccines?

    From the science and history of vaccines, there is no evidence of long-term effects.

    Vaccine side effects usually happen within a few days, and always within six weeks. Vaccines are quickly broken down and removed from your body, and so cannot cause side effects many months or years later. The only lasting impact of vaccination is the training it provides your immune system.

    Vaccines introduce proteins from a dangerous germ to the body’s immune system. In this way, the body can learn to identify and fight those germs off. Within a couple of weeks, no traces of the vaccine are left in the body. This is because the immune system destroys the proteins. Any other elements of the germ are quickly broken down.

    Like any medication or supplement (including vitamins), there’s a chance that there will be a serious side effect. These are rare, but they do happen. When it does, it's usually in the short term when the vaccine is stimulating the immune system. Learn about how Canada makes sure vaccines are safe for you and your family.

    It's far more likely that mRNA vaccines will be like other vaccines. Here's what you need to know about mRNA vaccines:

  • How do I know that the vaccine won't change my DNA?

    The vaccine doesn't change your DNA in any way.

    The mRNA from a COVID-19 vaccine never enters the nucleus of the cell, which is where our DNA are kept. This means the mRNA doesn't affect or interact with our DNA in any way. Instead, COVID-19 vaccines that use mRNA work with the body's natural defences to safely develop protection (immunity) to disease.

  • Can I get the vaccine if I have a health condition?

    People with health conditions, such as diabetes, high blood pressure, heart disease, respiratory diseases, including asthma or COPD, hepatitis B, C and HIV, can (and should) get vaccinated. This is because individuals with underlying medical conditions are more at risk of severe outcomes (such as hospitalization or death) from a COVID-19 infection.

    People with a weak immune system because of illness, treatment or an autoimmune condition should also be vaccinated. However, they may receive lower protection from the vaccine. For this reason, it is especially important that those who are moderately or severely immunocompromised stay up-to-date on their COVID-19 vaccines and receive all recommended doses. Visit getting vaccinated to learn more.

  • How were the COVID-19 vaccines developed so fast?

    Several factors allowed COVID-19 vaccines to be developed quickly without skipping or compromising any safety steps including:

    • Decades of mRNA research - In 2005, scientists figured out how to make synthetic mRNA safe for injection. After outbreaks of other coronaviruses in 2003 (SARS) and 2012 (MERS), scientists studied how the “spike protein” worked and how it could be used in vaccines. Learn more about the decades of research that went into the development of mRNA vaccines.
    • World-wide collaboration - Scientists and heath experts from countries around the world were focused on a common objective and sharing knowledge with each other. They were doing this to support the research and development into safe and effective COVID-19 vaccines. There was also dedicated funding to help support this work.
    • A fast-tracked approval process - Health Canada used a process that allowed manufacturers to submit data as it became available. Health Canada experts could then start the review process right away. Watch COVID-19: How vaccines are developed.
  • Are there side effects from COVID-19 vaccines?

    Visit after being vaccinated for more information.

  • What do I need to know about reports of myocarditis (heart inflammation) and/or pericarditis (inflammation of tissue around the heart) and COVID-19 vaccination?

    Both myocarditis and pericarditis are more common after COVID-19 illness (a viral infection) than after vaccination.

    While there have been rare reports of myocarditis / pericarditis after vaccination, the majority of cases have been mild and individuals recover quickly.

    Learn more about myocarditis / pericarditis and COVID-19 vaccines.

Before going for your vaccine

  • Is it safe to go to a public vaccination clinic?

    Our COVID-19 vaccination clinics have protocols in place to keep you safe from COVID-19. All health care providers, staff, volunteers and clients will be expected to follow all public health measures in the clinic.

  • Is free transit available?

    The following transit operators are providing free rides to and from your COVID-19 vaccination appointment:

    Use free transit to get your COVID-19 vaccination. Let the driver know which clinic you're going to.

  • What safety precautions can I take if I'm getting a ride to the clinic?

    If you're taking a taxi or getting a ride with a friend or neighbour:

    • Wear a mask
    • Sit in the rear passenger seat
    • Open the window, weather permitting
  • What do I need to know before going for my vaccine at a Public Health clinic?

    Before going for your vaccine

    • Take any regular medication
    • Make sure to eat before coming to the vaccination clinic to prevent feeling faint or dizzy while being vaccinated
    • Wear a loose-fitting top or a t-shirt
    • Dress for the weather, as you may need to wait outside

    What to bring

    • If you have a booked appointment, bring the booking appointment confirmation number you received when you made your appointment
    • Your green health card. You can still get vaccinated if you don't have a health card. Bring another government-issued photo identification with you.
    • A mask
    • An object or a distraction tool if you would like to get your mind off the needle. For example, a mobile device, fidget spinner or book.

    You may read the following documents from the Ministry of Health before going for your vaccine but it's not required. The health care provider will go over all the necessary documents and will answer any questions you may have at the clinic.

    Information sheet

    Consent form

  • Where can I get resources in other languages?

    If you need resources in languages other than English or French to prepare for your vaccine appointment, visit Ministry of Health COVID-19 documents in other languages.

  • What are the steps of getting vaccinated at Public Health COVID-19 vaccination clinic?

    All Public Health COVID-19 vaccination clinics follow a similar process.

    Step 1: Arrival

    Upon arrival, let clinic staff know what dose you're there for and if you have a booked appointment or you are a walk-in.

    Step 2: Screening

    Each person entering the vaccination clinic must complete an individual screen. Clinic staff will ask you the screening questions for COVID-19.

    You will be given a handout to read with information about the vaccine. The handout will also have a list of questions the health care provider will ask you in Step 4.

    If you're told not to enter the vaccination clinic because you're at increased risk of COVID-19 transmission, you will need to postpone your vaccination. Learn about the reasons to postpone your vaccine.

    Step 3: Check-in

    You will be called to a registration desk where your green health card will be scanned. If you don't have a health card, you can still get vaccinated.

    Step 4: Vaccination

    You will be directed to a table to get your COVID-19 vaccination.

    If you have fainted, or became dizzy with previous vaccinations or procedures, or if you have a high level of fear about injections, tell the health care provider so that appropriate supports can be offered.

    If the health care provider at the vaccination clinic advised you to defer your COVID-19 vaccination, you will need to defer your vaccination. If you booked an appointment, you can reschedule.

    Step 5: Waiting area

    You will sit in our waiting area for 15 minutes after getting vaccinated. Sit on a chair that has papers on the seat. This means your chair has been cleaned and disinfected. Make sure the sticker you're given is visible. Don't put your coat or sweater on top of the sticker.

    Step 6: Check-out

    You will receive a vaccine certificate that you can take with you. Keep this receipt in a safe place.

General information

  • What COVID-19 vaccines are approved for use in Canada?

    Health Canada has approved the following COVID-19 vaccines for use in Canada. All vaccines approved in Canada are proven safe, effective and of high quality.

    mRNA vaccines

    Protein-based vaccine

    Plant based virus-like particle vaccine

    Viral vector vaccines

    Hundreds of millions of people have received mRNA COVID-19 vaccines around the world. Because of this, a large amount of evidence has been collected on the safety and effectiveness of these vaccines. The evidence shows they provide excellent protection against severe illness and hospitalization from COVID-19 and that they have a good safety profile. This is why the National Advisory Committee on Immunization strongly recommends individuals get vaccinated with an mRNA COVID-19 vaccine for their primary series and any booster dose(s) unless they are unable to due to a valid health reason.

    Those who cannot be vaccinated with an mRNA COVID-19 vaccine may contact Public Health to request a dose of Novavax or Johnson & Johnson. Visit getting vaccinated to learn more.

  • Why should I get vaccinated if I may only get mild symptoms from a COVID-19 infection?

    Some people who get COVID-19 may just experience mild symptoms. However, this is not always the case. COVID-19 can be a serious illness for anyone and for some people symptoms can last for months.

    Getting vaccinated virtually eliminates the risk of serious illness and death. When compared to unvaccinated individuals, those with at least two doses of COVID-19 vaccine are not only less likely to experience a COVID-19 infection, they are far less likely to end up in the hospital or the ICU if they do get infected. Check out the data from the Ontario COVID-19 Science Advisory Table.

    Also, both adults and children can suffer from post COVID-19 condition (also known as long COVID). This refers to the longer-term effects some people experience after their COVID-19 illness. Symptoms of this can be quite different from those experienced during the initial infection. The best way to prevent it is to take actions to prevent COVID-19, like getting vaccinated. Learn more about post-COVID-19 condition.

  • If I had COVID-19 should I still get the vaccine?

    Yes, you should still get your vaccine.

    A previous infection of COVID-19 can provide some protection. However, getting vaccinated can strengthen and provide longer lasting protection against COVID-19.

    Compared to previous variants, Omicron has a higher reinfection rate for people who had a previous COVID-19 infection. This makes getting vaccinated even more important to protect yourself and others in your community.

    Learn about:

  • Which vaccine will I get for my booster at a Public Health clinic? What if it's different than my previous doses?

    Individuals under 30 years of age:

    Pfizer - Reports of myocarditis (inflammation of the heart) and pericarditis (inflammation of the tissue surrounding the heart) remain rare after vaccination. When it does happen, it seems to be more often in young adults - particularly those under the age of 30. The evidence suggests it's more common following vaccination with Moderna compared to Pfizer.

    Individuals 30 years of age and older:

    Moderna - Ongoing research suggests that over time, Moderna has less waning immunity and maintains a high effectiveness - especially in older adults. This means you're likely to have longer lasting and potentially stronger protection with the Moderna vaccine compared to Pfizer.

    Moderna and Pfizer vaccines use a similar mRNA technology. This means the vaccines are interchangeable and safe to mix. Canada's National Advisory Committee on Immunization made this recommendation after carefully reviewing research on safety and effectiveness. Countries around the world, including the United States, are also using a different vaccine for the booster dose as compared to the previous doses.

  • How do I report my COVID-19 vaccination if I received it outside of Ontario?

    If you have received a COVID-19 vaccination outside of Ontario, report your vaccination using the online form..

    Make sure to still keep your original vaccination certificate (record of vaccination) in a safe place.

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