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Vaccine FAQ

It can be overwhelming to navigate the large volume of COVID-19 vaccine information online, especially if you are unsure about the safety of the vaccine. If you or those around you are hesitant to get vaccinated, it can help to have accurate information in a centralized place.  

On this page, you can find answers to many common vaccine-related concerns. These concerns are understandable, especially for vulnerable populations who have faced centuries of harm at the hands of western science. Ultimately, vaccination is one of the best steps you can take to protect yourself and your community from COVID-19 and related complications. 

How to use this resource effectively 

The information in the panels below can help you answer questions for folks who are hesitant to get vaccinated. In those situations, try your best to understand their specific concerns and address only those concerns based on the information available here. Providing them with all the reasons why someone may be concerned can increase vaccine hesitancy, so it is best to focus on their specific questions.

Why get the COVID-19 vaccine? 

COVID-19 is a concern on individual, community, and systems levels. Each of us must take individual measures to protect our own health and well-being. However, the pandemic will not be over until our local and global communities do their part with more systemic efforts. 

We enter lockdowns not only when case numbers rise, but also when hospital ICUs are at capacity. Our healthcare system doesn’t have the resources needed to handle the influx of COVID cases in addition to other healthcare emergencies. Ontario is on the brink of enacting a triage protocol, where doctors will be forced to prioritize the people who are less likely to die. Getting your COVID-19 vaccine helps relieve pressure on hospitals.  

In Canada, the four available vaccines are by Pfizer, Moderna, Johnson & Johnson (Janssen), and AstraZeneca. All the COVID-19 vaccines are effective at reducing the risk of serious symptoms and preventing hospitalizations. Thus, all the COVID-19 vaccines will help us get out of this pandemic.

If you would like to learn about how the COVID-19 vaccines work, visit our vaccines information tab. 

References: Building vaccine confidence, Vaccine definition, Virus definition, Definitions: Coronavirus, SARS-CoV-2, COVID-19, World Health Organization: Origins of SARS-CoV-2

Expandable List

Were the COVID-19 vaccines developed too quickly to be safe?

The COVID-19 vaccines were developed faster than previous vaccines, but this does not mean that their safety was compromised. 

It takes more time to develop other vaccines because insufficient funding often delays vaccine production. However, many countries immediately invested in research for the COVID-19 vaccinesVaccine manufacturing facilities were built well in advance, which sped up the development process.  

Additionally, vaccine trials were conducted more quickly by running phases simultaneously, thanks to increased funding. These trials used the same number of participants, data, and safety tests as for any vaccine approved in Canada, but they took less time.  

The ethics and safety of the COVID-19 vaccine trials were ensured by independent reviewersso we can feel confident in their results. 

References: Immunize BC, Nebraska Medical

Are some of the COVID-19 vaccines more effective? Should I try to get a better one?

You should get whichever COVID-19 vaccine is available to youAll the COVID-19 vaccines are effective at preventing most symptomatic infection and nearly all hospitalization or death.  

Additionally, since vaccine trials never directly compared different COVID-19 vaccines to each other, it is difficult to say that one vaccine is more effective than another. All the vaccines can protect you. You should get whichever vaccine is available to you. 

References: Immunize BC FAQ, Immunize BC vaccine effectiveness

I’ve heard that mRNA is new technology. How can I trust that it’s safe?

It is true that the mRNA vaccines have never been on the market previously, but this does not mean that they are less safe than other vaccines. mRNA vaccines have been studied in humans for other diseases such as rabies. In those human trials, mRNA vaccines were found to be safe, but they were not used because other vaccines worked better for those specific diseases. For COVID-19, mRNA vaccines are safe and effective. 

mRNA vaccines have met the same effectiveness and safety standards as any other available vaccines.

References: CDC: mRNA vaccines, European commission 

Will the COVID-19 vaccines alter my DNA?

No. None of the COVID-19 vaccines can alter your DNA. 

Viral vector vaccines use adenoviruses to deliver viral DNA to the nucleus of your cell, but they cannot alter your DNA. These vaccines also cannot replicate, which increases their safety. 

The mRNA from the mRNA vaccines does not enter the nucleus of the cell where the DNA is stored. The mRNA is degraded by your body after it boosts your immune system. These vaccines also cannot alter your DNA. 

References: Viral Vector Vaccines, mRNA Vaccines

Do the COVID-19 vaccines make you sick with COVID-19 or other illnesses?

The vaccine does not make you sick with COVID-19. The side effects of vaccination are normal signs that the vaccine is building your immunity against the disease. 

You can use various methods to manage side effects. For example, you can take over-the-counter medications such as ibuprofen. 

If the side effects last longer than a few days or they are severe, please contact a healthcare provider for guidance. If you have an allergic reaction, please call 911 for immediate medical care. 

ReferencesMcGill University vaccines information, CDC vaccines, CDC vaccine side effects

I’ve heard that the AstraZeneca vaccine blood clots. Is this true?

A small number of AstraZeneca vaccine recipients have had blood clots. However, this is extremely rare.

It is important to weigh the small risk of blood clotting against the benefits of getting the AstraZeneca vaccine. You are also more likely to get a blood clot with COVID-19 than with the vaccine. When you get vaccinated, you are less likely to get COVID-19. Further, you are protected from other risks of COVID-19 too, such as lung damage and death. There is a small chance of having a blood clot, but Canadian doctors can help treat that.  

References: Vaccine induced blood clots, Hamilton Health Sciences, Global News, CTV News

I’ve heard that people can experience long-lasting side effects of the COVID-19 vaccine. Is this true? 

Side effects should disappear after a few days. To manage side effects, you can consider methods such as taking over-the-counter ibuprofen or applying a clean wet washcloth to the injection site. 

If the side effects last longer than a few days or they are severe, please contact a healthcare provider for guidance. If you have an allergic reaction, please call 911 for immediate medical care. 

References: McGill, CDC side effects, CDC and FDA on J&J vaccine

I’ve heard that COVID-19 vaccines contain toxins like mercury and aluminum. Is this true and, if so, should I be worried?  

No, this is not true. The COVID-19 vaccines available in Canada contain neither mercury nor aluminum.  

It is also important to know that the use of mercury or aluminum in other vaccines is not necessarily harmful. In other vaccines (not for COVID-19), mercury is present in a non-toxic form. It prevents bacterial contamination of those vaccines. In other vaccines (not for COVID-19), aluminum is used in safe amounts. It improves the effectiveness of those vaccines.  

References: York Region, FDA vaccine fact sheet, Pfizer and Moderna,, FDA vaccine preservatives, Oregon live, CDC vaccines

I’m not at high risk but I’m eligible for a COVID-19 vaccine, should I wait to get it so others who need it more can get it before me?

No, you should not delay getting vaccinated if you are eligible. If you are infected, you could still suffer from COVID-19 related complications. 

In Canada, vaccine rollout is designed to target vulnerable communities and hotspot regions, so there is a reason why you are being prioritized for vaccination. Getting vaccinated can help slow the spread of infection, protect those who can’t be vaccinated, and take pressure off hospitals.  

Delaying your vaccination won’t help vaccines reach vulnerable individuals. If you are eligible and there are appointments available, you should not hesitate to book your vaccination. 

References: Risk to Young Adults, US concerns in January, CTV News

Do I need the vaccine if I’ve already had COVID-19?

Yes, you should be vaccinated even if you’ve already had COVID-19, because there have been cases of COVID-19 reinfection. If this happens, you can still pass the virus to others.  

To get the vaccine, wait until your isolation period is over. If you visit a vaccine clinic before this period is over, you might expose others to the coronavirus. 

If you have already had COVID-19, talk to your doctor to determine the right time for getting vaccinated.  

References: Hamilton vaccine FAQ, Immunize BC FAQ

Is COVID-19 a serious threat to young adults?

Yes, COVID-19 can harm young adults. Although young adults are less likely to die from COVID-19, they can develop severe symptoms. Young people with obesity, diabetes, or high blood pressure are especially susceptible. 

If young adults with COVID-19 are asymptomatic, they might unknowingly pass the virus to other people. This can be harmful if those people are at high risk for severe disease or death. 

References: Hopkins medicine

I am an international student without an OHIP card. Can I get a vaccine in Ontario?

Note: The phone number listed is only for those who are already eligible and living in Hamilton.

Yes, international students can get the vaccine in Ontario if they are eligible! To find out if you are eligible, enter in your location and criteria into the Ontario booking website.

However, you may not be able to book your vaccination appointment online. To book your vaccine in Hamilton once you’re eligible, you can call the Public Health Services COVID-19 hotline at 905-974-9848 and dial option 7. 

I am Black or Indigenous, and I don’t trust the safety of the COVID-19 vaccines. How can I trust that the vaccine is for me?

Structural inequalities have led Black and Indigenous people to be disproportionately impacted by COVID-19. Thus, these communities are now being prioritized for vaccination.  

Distrust in COVID-19 vaccine is understandable, especially in Black and Indigenous communities. There is a history of harm caused by Western healthcare providers and systems. 

It might help to read the stories of Black and Indigenous people who have received the vaccine. You can find some stories below. 

If you are Black or Indigenous, you can call the Public Health Services COVID-19 hotline at 905-974-9848. Dial option 7 to book your vaccine.  

If you are a Six Nations Band member, you can also book your vaccine at  

If you are not comfortable getting vaccinated at the clinic closest to you, you can visit a pop-up vaccine clinic created by and for Indigenous peoples. 

Click here to find out more about Hamilton’s Mobile Indigenous Clinic (Operating May 8 and May 9)

Article: More than medical mistrust

Article: I’m a Black doctor who didn’t trust the COVID Vaccine. Here’s what changed my mind.

Article: A Nursing Researcher’s Experience in a COVID-19 Vaccine Trial

Do the COVID-19 vaccines contain animal products?

No. Animal products are sometimes to improve the vaccine’s efficacy or to stabilize the vaccine during storage. However, none of these substances have been used in any of the COVID-19 vaccines currently available in Canada. Thus, there are no animal products in the vaccines by Moderna, Pfizer, Janssen/Johnson & Johnson, and AstraZeneca. 

References: CAMH, Hamilton FAQ, Gov.UK

Do the COVID-19 vaccines contain fetal material?

Note: None of these fetal cell lines are from recent abortions nor are they supporting abortion clinics today. Several religious organizations have released statements regarding the use of fetal cells for vaccine production and recognition of the importance of vaccines in saving human lives today. Please consult your religious leaders if this is something you are concerned about. If you see something online suggesting that there are fetal tissues or fetal cells in the vaccines themselves, know that this is misinformation. 

No, none of the COVID-19 vaccines contain any aborted fetal cells or tissue. 

However, fetal cell lines were used in the production and confirmation of some vaccines. Fetal cell lines are replicated indefinitely from fetal tissue for science, but they are not the original aborted fetal cells or tissue. 

Viral vector vaccines are produced using fetal cell lines. After the vaccine is formed, the vaccine is removed from the cells. None of the fetal cells are in the vaccine. After the vaccines are produced, viral vector vaccines and mRNA vaccines use fetal cell lines to confirm the vaccines activate the immune response correctly. 

The fetal cell lines used in COVID-19 vaccines are replications of tissue from elective abortions that happened 30 to 60 years ago. These cell lines were chosen because they are safe and reliable for vaccine development. 

References: Hamilton FAQ, Nebraska Med, Kare News, Vatican, Ethics and Religious Liberty Commission

The risk of COVID-19 in Canada doesn’t seem as bad as other countries, do I really need to get vaccinated? 

Canada’s healthcare system is under a lot of pressure. Hospitals are filled with COVID-19 patients, so we are running out of resources to help people who suffer various emergencies. In Ontario, healthcare workers might be forced to start triaging care. Thus, people with a lower chance of survival will be denied proper care. 

By getting vaccinated, you can help lessen the pressure on hospitals. Vaccines protect us from COVID-19 and prevent hospitalization and they can help us overcome the pandemic. 

References: CBC news: cases in Canada, CTV news: cases in Canada, CTV news: need for doctors, CTV news: Ontario triage protocol, Global news: Ontario triage protocol

What do anti-vaccination groups believe and advocate for?

“Anti-vaxxer” refers to people who actively oppose public provision of vaccines. Anti-vaxxers are not the same as people who are skeptical of certain vaccines. 

The anti-vaccination movement resurfaced when Andrew Wakefield, a doctor, published a study claiming that there was a causal link between the MMR vaccine and autism. His research had used flawed methods, and his claims were shown to be false. The study was discredited, and Wakefield had his medical license revoked. 

False claims and unethical studies spread quickly online and in media. It is important to get your vaccine information from reliable sources. 

References: Cureus: The Anti- vaccination Movement