Vaccination for COVID-19 – Frequently asked questions

Vaccination for COVID-19 FAQ

The Canadian Red Cross is encouraged by the news of COVID-19 vaccines being administered across the country and reminds people to continue to seek information from a trustworthy source, including the Public Health Agency of Canada and local and provincial health authorities.
As we move towards widespread, lasting control of COVID-19 through safe and effective vaccines, it’s essential for everyone in Canada to continue following public health recommendations to prevent further spread. It is more crucial than ever that people remain vigilant. We encourage everyone, including those who are vaccinated, to continue physical distancing, practice frequent hand hygiene, wear face masks, and follow any additional measures laid out by public health authorities across the country.

Is the vaccine considered to be effective and safe?

We understand there may be some misinformation circulating about the COVID-19 vaccine and its effects. It is essential for people to follow trusted sources for accurate and up-to-date information about vaccines, including the Public Health Agency of Canada and local and provincial health authorities.
The role of the Canadian Red Cross is to support vaccination efforts in coordination with local health authorities. The Red Cross does not replace Health Canada, which approves vaccines and determines risk and efficacy using evidence-based global standards.
Learn more about approved vaccines on Public Health Canada website

The COVID-19 vaccine was developed so quickly, how can it be trusted?

Scientists prioritized COVID-19 vaccine development because of the global emergency. The vaccines for COVID-19 have been through the same amount of testing and safety processes as other vaccines.
Vaccines approved for use in Canada are reviewed through Health Canada’s independent drug authorization process, which is recognized around the world for its high standards and rigorous review.
Learn more about how vaccines are developed on this video from Public Health Canada

Can the vaccine give me COVID-19?

No. None of the COVID-19 vaccines approved in Canada or currently in development use the live virus that causes COVID-19. It usually takes the body a few weeks to build immunity after receiving a vaccine. It is possible that someone could become infected with the COVID-19 virus before or just after getting the vaccine and get sick. This happens because the vaccine has not had enough time to provide protection in the body.

How do we know there won’t be long-term side effects?
The majority of vaccine side effects occur shortly after receiving a vaccine, not months or years later. Once a vaccine is approved, scientists and government agencies continue to monitor its safety to identify any rare side effects. These monitoring efforts also focus on particularly vulnerable people, including people with specific medical conditions, or pregnant women.

Can RNA or DNA vaccines change my DNA?

No. mRNA is not able to alter or modify a person’s genetic makeup (DNA). 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 does not affect or interact with our DNA in any way. Instead, COVID-19 vaccines that use mRNA work with the body’s natural defenses to safely develop protection (immunity) to disease.

Can people who have already tested positive for COVID-19 get the vaccine?

Yes. Due to the severe health risks associated with COVID-19 and the fact that re-infection with COVID-19 is possible, people should still get vaccinated even if they have been sick with COVID-19 before. 

How quickly does the vaccine work? How long does it last?

According to Health Canada, in trials the Pfizer-BioNtech vaccine was 95 per cent effective beginning one week after the second dose (given 21 days after the first dose).  The Moderna vaccine was 94.1 per cent effective in trials beginning two weeks after the second dose (given one month after the first dose).
We don't yet know for sure how long protection will last. It is likely to be at least several months, but it may be that repeat vaccinations are needed. Researchers are studying this closely.

If I get a COVID-19 vaccine, will I still need to take other precautions such as physical distancing and wearing masks?

Yes. Health authorities recommend that everyone – including those who have been vaccinated – continue using all available tools to help stop the spread of COVID-19, such as physical distancing, frequent hand washing and the use of masks. This will provide the best possible protection against the spread of COVID-19.

Will COVID-19 vaccines provide long-term protection?

Ongoing research is needed to show if COVID-19 vaccines provide long-term protection. Additional doses of the vaccine may be needed to provide continued protection. It will take ongoing evaluation over several years to understand how our immune systems respond to this virus and how vaccines assist in that response.


Should children be vaccinated?

According to Health Canada, at this time the Pfizer-BioNtech vaccine is approved for people who are 16 years of age or older, and the Moderna vaccine is approved for people who are 18 years of age or older. The vaccines’ safety and effectiveness for individuals younger than those respective ages has not been determined.

I think I have a low risk of contacting COVID-19, do I need to be vaccinated?

Anyone, at any age, can get sick with COVID-19 and become seriously ill or die. Furthermore, asymptomatic people infected with the virus can be contagious and the virus can spread from them to other people. For these reasons, it is important to consider that getting vaccinated may also protect people around you, particularly people at increased risk for severe illness from COVID-19. There's no evidence that any of the current Covid-19 vaccines can completely stop people from being infected and consequently prevent transmission. In addition, based on available information about vaccines for other diseases and early data from clinical trials, experts believe that getting a vaccine can also prevent severe illness if you do get COVID-19.

Does the COVID-19 vaccine protect me from new strains of the virus?

Current vaccines were designed around earlier versions of coronavirus, but scientists believe they should still work against the new ones, although perhaps not quite as well. Even in the worst-case scenario, vaccines could be redesigned and tweaked to be a better match - in a matter of weeks or months, if necessary, say experts.

Health Canada is monitoring the emerging variants closely and will work with manufacturers and international regulators to assess the impact of the new variants on the effectiveness of approved vaccines and treatments.
Visit the Public Health Agency of Canada to learn more on COVID-19 variants 

More information from official sources

Vaccines and treatments for COVID-19: Progress - Health Canada
Coronavirus disease (COVID-19): Vaccines - World Health Organization

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