COVID-19 Vaccine FAQs

Answers to common and evolving questions around a COVID-19 vaccine

When will a vaccine be available to the general public?

Four vaccines, manufactured by Pfizer-BioNTech, Moderna, Astra-Zeneca and Janssen (a division of Johnson & Johnson) are available under Emergency Use Authorization (EUA).  Distribution of vaccines by the Federal government has started and is on a province-by-province basis usually based on population. Each province has a phased approach for distribution. Click here for up-to-date information. 

Who will get the COVID-19 vaccine first?

Initially, there will not be enough doses available, which means certain groups will be prioritized to receive the vaccine first and not everyone would be able to get vaccinated right away. But supplies will increase over time, and all adults should be able to get vaccinated later in 2021. The goal is for anyone who wants to get vaccinated be able to do so once a COVID-19 vaccine is widely available. In the case of a limited supply, the Alberta Government is recommending the following priority groups.  Click here for the list.

Are there different types of vaccines, and is one better than others?

We don’t know if one is better than another, but they do work in different ways:  

  • Messenger RNA (mRNA) vaccines contain a copy of genetic information that looks like the SARS-CoV2 (the virus that causes COVID-19) virus’s information that causes COVID-19.  This gives our cells instructions for how to make a harmless protein that is unique to the virus. After our cells make copies of the protein, our bodies recognize that the protein should not be there and build T-lymphocytes and B-lymphocytes and antibodies that will remember how to fight the virus that causes COVID-19 if we encounter the virus in the future. The Moderna and Pfizer vaccines are mRNA vaccines. 
  • Viral vector vaccines contain a modified, weakened virus (not the COVID-19 virus) that delivers a message for a protein like the spike protein of the SARS-CoV2 virus to be made by our cells.  By instructing cells to make large amounts of antigen, which then triggers an immune response, the vaccine mimics what happens during natural infection with SARS-CoV2 and stimulates an immune response that will protect you from future encounters from the COVID-19 virus. The AstraZeneca and Johnson and Johnson vaccines are examples of these. 
  • Protein-based vaccines contain harmless coronavirus proteins, not the whole virus, and produces an immune response against the virus. The Novavax vaccine is an example of protein-based vaccines.

What are the potential vaccine side effects?

Local and systemic side effects can occur after vaccine. These include local tenderness, swelling, and erythema. Relatively common systemic symptoms include fever, myalgias, and headache. In the Pfizer vaccine trial, systemic symptoms were more common in younger age groups and after the second vaccine dose. Systemic symptoms are similar to COVID-19 disease so patients receiving vaccine should be counseled on the possibility of these symptoms occurring in the first few days after each vaccine dose.

Is the AstraZeneca vaccine safe?

On March 22, AstraZeneca has announced positive high-level results from an interim analysis of the AstraZeneca US Phase III trials of AZD1222. The data show that the vaccine demonstrated statistically significant vaccine efficacy of 79% at preventing symptomatic COVID-19 and 100% efficacy at preventing severe disease and hospitalisation. In particular:

  • This AstraZeneca-led US Phase III trial included two doses administered at a 4 week interval.
  • Vaccine efficacy was consistent across ethnicity and age. Notably, vaccine efficacy was 80% in participants aged 65 years and over, who represented approximately 20% of participants.
  • This interim safety and efficacy analysis was based on 32,449 participants across 88 trial centres in the US, Peru and Chile accruing 141 symptomatic cases of COVID-19. The vaccine was well tolerated, and the data safety monitoring board (DSMB) identified no safety concerns related to the vaccine.
  • During the interim analysis, the DSMB also conducted a specific review of thromboembolic events across the US trial data. The DSMB found no increased risk of thrombosis or events characterised by thrombosis among the 21,583 participants receiving at least one dose of the vaccine. The specific search for cerebral venous sinus thrombosis (CVST) found no events in this trial.

These results add to the growing body of evidence that shows this vaccine is well tolerated and highly effective against COVID-19 across all adult age groups. Read AstraZeneca's File Official Company Statement.

Are there differences in vaccines that may require two shots versus just one?

Different types of vaccines require different types of administrations. For some types of COVID-19 vaccines, the first shot would prime the immune system, helping it recognize the virus and the second shot would strengthen the immune response. Each of the vaccines authorized in Canada require two doses. There isn’t information available on the need for booster shots—that would fall into long-term efficacy data which, we don’t have yet.  

How effective are the Pfizer and Moderna vaccines?

In clinical trials both vaccines have shown approximately 95% efficacy, which is very promising. This means that in the clinical trials, the vaccine prevented 95% of the clinical cases compared to the placebo group recipients. However, it’s important to note that we don’t know what will happen in the “real world” until people start being vaccinated.

Is it possible to get COVID-19 from the vaccine?

No. Like the flu shot and other vaccines, COVID-19 vaccines cannot give you the virus.

Will people who had COVID-19 be able to get the vaccine? Do they need to get it?

If you had COVID-19 and recovered from it, you probably have some antibodies, but it is still unknown as to how long that protection against reinfection will last. Some early evidence suggests natural immunity may not last very long.

How long does the COVID-19 vaccine protect me? Will I have to get one every year like the flu shot?

This is It is currently unknown. When we know how long immunity from the vaccine will last, decisions can be made about timing of re-vaccination.

Does the shortened approval timeframe mean that a vaccine is less safe? What is the approval process for vaccines?

No, Canada's independent authorization process is recognized around the world for its high standards and rigorous review. The approval of the vaccine is supported by evidence that it is safe, effective and of good quality. And each vaccine producer must follow a multi-step approval process that includes sharing research from clinical trials.  Government of Canada Vaccine authorization information

Am I “immune” to the virus after receiving a COVID-19 vaccine?

It depends. Immunity is when the body can resist a particular disease, and vaccines help build up that immunity by stimulating antibody production and immune cells (T and B lymphoctyes) for future protection. Immunity works best at the community level so when enough people are vaccinated then an infected individual has nobody to spread the disease to. A vaccination can help prevent getting the infection or at least keeping the severity of the infection to a mild level. Everyone’s immune system responds a little differently.

Do we need to keep wearing masks?

Yes! The vaccine will not replace the basic safety measures of wearing masks, social distancing and handwashing.

Even when a vaccine is widely available, additional measures like masks will still be necessary until the public health threat has subsided. It is an important safety measure not only for yourself but for those around you.

I have allergies. Should I be concerned about an allergic reaction to the vaccine?

Having seasonal or food allergies does not mean you will experience a reaction to the vaccine.  If you have a history of severe allergic reactions you should talk to your physician before receiving an mRNA COVID-19 vaccination. They will help you determine if you have experienced a severe allergic reaction (e.g., anaphylaxis) to any component of a COVID-19 vaccine listed in the prescribing information, in which case the vaccine would not be recommended. Established COVID-19 vaccination protocols suggest all persons be observed after vaccination for a minimum of 15 minutes.

Can transplant patients receive the COVID-19 vaccine?

PLEASE check with your physician first before receiving the vaccine.   Although further data is needed, based on the opinion of experts transplant patients may receive the vaccine. Experts believe that based on the mechanism of action of mRNA vaccine, there is no reason to suspect that adverse events will be any different than in the general population. Based on expert opinion, the potential benefits of vaccine likely outweigh theoretical risks. mRNA leads to a vaccine-specific immune response and the generation of alloimmunity or rejection following vaccination is unlikely based on the mechanism of the vaccine, and broad experience with other types of vaccines in the transplant population. For optimum vaccine efficacy, it is suggested that:

• When possible, vaccine be administered in the pre-transplant setting with the final dose at least 1-2 weeks prior to transplant

• It is not necessary to put a patient on hold for transplant while waiting for vaccination

• In post-transplant patients, wait at least 1 month after transplant to provide the vaccine regardless of induction therapy.

• If the patient undergoes transplantation between the first and second doses, provide the second dose at 1 month after transplant. Additional doses are not recommended.

• In patients undergoing active treatment for acute rejection, vaccination can be deferred for a 1-month period.

• Avoid giving vaccine for at least 3 months after rituximab for improved efficacy

• If a patient has had COVID-19 before, wait 90 days from diagnosis and symptom recovery before giving COVID-19 vaccine.

• Since there are no vaccine co-administration studies, avoid giving other vaccines within 2 weeks of the COVID-19 vaccine dose.

• Vaccine should not be given to patients that have had a known anaphylactic reaction to medication (this is currently under review)

• Since efficacy is expected to be lower than the general population, it is strongly recommended that patients continue to practice infection control measures. In addition, household contacts of the transplant recipient should also be vaccinated when possible.

Source: These guidelines were produced by the UHN Ajmera Transplant Center and endorsed by the Canadian Society of Transplantation.

When will the vaccine be available for transplant patients?

In Canada, the priority groups are currently long-term care residents/workers, healthcare workers, and indigenous populations. When there is sufficient vaccine supply, other groups will also be identified and eventually the vaccine will be rolled out to the general population. Thus, it may likely be March or April 2021 when vaccination can be given to transplant patients. At that time, additional vaccines may be authorized

Source: These guidelines were produced by the UHN Ajmera Transplant Center and endorsed by the Canadian Society of Transplantation.

What about pediatric transplant patients?

The vaccine is currently not approved for children under 16 years of age, but once approved, we expect similar recommendations to apply to pediatric transplant recipients.

Source: These guidelines were produced by the UHN Ajmera Transplant Center and endorsed by the Canadian Society of Transplantation.

What are the national and international recommendations for immunocompromised population?

The CDC Advisory Committee on Immunization Practices (ACIP;U.S.) and the Joint Committee on Vaccination and Immunisation (JCVI; U.K.) has stated that vaccine can be given to immunocompromised population when it becomes available. The JCVI has listed patients with a transplant as being a prioritized vulnerable population. The AST (American Society of Transplantation) and ISHLT (International Society for Heart and Lung Transplantation) have also recommended COVID-19 vaccine to be given to transplant patients when available. Health Canada and FDA have not contraindicated the vaccine for immunocompromised although have stated that there are no data on efficacy and adverse events in this population. The National Advisory Committee on Immunization in Canada has not recommended vaccination for the immunocompromised population as a whole due to lack of efficacy and safety data in this population. However, they have stated that vaccination may be given on a case-by-case basis after considering the risk vs. benefits and letting individuals know that data on efficacy and safety are lacking. Efficacy may be lower in the immunosuppressed state and immunocompromised patients should continue to practice infection control measures against COVID-19.

Source: These guidelines were produced by the UHN Ajmera Transplant Center and endorsed by the Canadian Society of Transplantation.

Page Last Updated: 23/03/2021