Frequently Asked Questions

Vaccines are safe and reliable, and can both protect you from COVID-19 and make your symptoms milder if you do get it. When a large percentage of the population becomes immune to COVID-19, the spread of the virus will slow down and may stop. As evidence is evolving on COVID-19 vaccines, additional research will help us to determine what percentage of the population needs to be vaccinated in order to stop its spread.

Vaccines that have been authorized by Health Canada are safe, reliable and can help protect you, your family and our community from COVID-19. The Pfizer-BioNTech, Moderna, AstraZeneca and Janssen COVID-19 vaccines were authorized by Health Canada after thorough and independent reviews determined that they meet stringent safety, efficacy and quality requirements.

As a reminder, vaccines are just one important tool to help stop the spread of the virus and it is important that we all continue to follow public health measures and take everyday actions to stop the spread of the virus.

Vaccination against COVID-19 is voluntary, but strongly encouraged. The goal is for every Ontarian to get a COVID-19 vaccination if they want one, as soon as enough doses are available from manufacturers.

Vaccines that have been authorized by Health Canada are safe, reliable and can help protect you, your family and our community from COVID-19. The Pfizer-BioNTech, Moderna, AstraZeneca and Janssen COVID-19 vaccines were authorized by Health Canada (external link) after thorough and independent reviews determined that they meet stringent safety, efficacy and quality requirements.

As a reminder, vaccines are just one important tool to help stop the spread of the virus and it is important that we all continue to follow public health measures and take everyday actions to stop the spread of the virus.

COVID-19 vaccination helps protect you by creating an antibody response without having to experience the illness of COVID-19. Getting vaccinated can reduce your risk of developing COVID-19 and make your symptoms milder if you do get it.

The Pfizer-BioNTech and Moderna COVID-19 vaccines use a method called messenger RNA (mRNA) technology. The mRNA in the vaccine tells the body’s cells to make "spike proteins," similar to what is found on the COVID-19 virus. The immune system responds to the spike proteins by making antibodies. These new antibodies will break down the spike proteins and get rid of them. The new antibodies will protect against COVID-19 infection in the future. The mRNA is broken down by the body shortly after injection and cannot affect the body’s DNA.

The AstraZeneca and Janssen vaccines are viral vector vaccines. Unlike the Pfizer-BioNTech and Moderna vaccines, which store the instructions to build spike proteins in RNA, the AstraZeneca and Janssen vaccines use DNA. The vaccines uses a harmless virus (called an adenovirus) as a delivery system. This is called a viral vector. Once the vaccine containing the viral vector enters the body, the vector virus produces the SARS-CoV-2 spike protein. Just like the mRNA vaccines, the immune system responds to the spike proteins by making antibodies. These new antibodies will break down the spike proteins and get rid of them. The new antibodies will protect against COVID-19 infection in the future.

The COVID-19 vaccines do not contain live vaccines. You cannot get COVID-19 from a vaccine.

Yes. Those who previously tested positive for COVID-19 should still be vaccinated to protect themselves and others. There are severe health risks associated with COVID-19 and re-infection with COVID-19 may be possible.

At this time, experts do not know how long someone is protected from getting sick again after recovering from COVID-19. The immunity developed after having an infection, called natural immunity, is different from person to person. Some early evidence suggests natural immunity may not last very long. We need more information on how well the vaccine works to be able to assess how long immunity from the vaccine will last.

Yes, it is important for everyone to continue to practice public health measures even after they have been vaccinated. This includes:

• covering your mouth and nose with a mask;
• covering coughs and sneezes with a tissue or sleeve;
• washing hands often and avoiding touching your eyes, nose or mouth;
• staying at least two metres (six feet) away from others outside of your household;
• self-isolating when sick; and
• following all Provincial orders and regulations.

It is very important to understand that while the vaccine will help protect you from becoming severely sick with COVID-19 symptoms, it is possible that you can still spread the virus even after being fully vaccinated. Researchers are still studying what protection the COVID-19 vaccines provide, including whether you can have an asymptomatic infection (no symptoms) and spread the virus to others even though you have been vaccinated. While you may have received the vaccine, there are many others in our community waiting to be vaccinated who are still susceptible to the virus. Continuing to follow public health measures after vaccination will help to protect other members of our community.

Finally, after vaccination, it takes time for your body to build immunity. While you can expect very good protection a few weeks after the first dose of vaccine, full protection is not reached until a person has received both doses of the vaccine. 

For more information on protecting yourself and others public health guidance, visit halton.ca/COVID19.

While still being studied, the COVID-19 vaccines that have been approved in Canada appear to provide protection (external link) against the variants of concern. The vaccines provide a broad immune response so virus mutations should not make vaccines completely ineffective.

Health Canada continues to monitor the effectiveness of all COVID-19 vaccines. Further research is being done to tailor the vaccines to provide enhanced protection against all variants. Health Canada announced that modified COVID-19 vaccines for variants will be made available quickly to Canadians (external link).

All COVID-19 vaccines approved for use in Canada are effective at preventing serious COVID-19 illness, hospitalization and death. Based on study data available (click on each percentage to access studies), the following table presents the estimated efficacy between the first and second vaccine doses:

CI = confidence interval; *from day 22 up to day 90 after dose 1; **estimate of vaccine efficacy for dose interval of more than 12 weeks

Our bodies usually take at least two weeks to develop immunity after receiving a COVID-19 vaccine. Receiving a second dose months or even years after an initial vaccine can boost antibodies generated through vaccination to a higher level, in fact for many vaccines, a longer interval results in higher antibody levels. Most vaccine manufacturers specify minimum intervals between doses, not maximum intervals.

On Friday March 5, 2021 the province announced that the National Advisory Committee on Immunization (NACI) has recommended that the second dose of the vaccine can be given up to 16 weeks after the first dose (external link). This recommendation was made based on emerging evidence that the first dose of the COVID-19 vaccines currently available provides substantial protection against symptomatic disease, severe illness and death. The Province has accepted NACI’s recommendations and has advised that second dose appointments be extended starting March 10, 2021.

Halton Region has followed provincial direction and has extended the time interval for the second vaccine dose from 21 days to 16 weeks. The interval for 21-28 days between doses remains for residents of long-term care homes, retirement homes and assisted living facilities, recipients of organ transplants and individuals with malignant hematological disorder, non-hematological disorder tumor receiving chemotherapy (external PDF).

Delaying the second dose allows for more people to be immunized faster. This means that high risk individuals will receive protection earlier. Based on the current supply of vaccines, the Public Health Agency of Canada has identified a delayed second dose will allow Canada to provide a first dose of vaccine to approximately 80% of all Canadians 16 years of age and over by the end of June (external link).

For best results, it is important that everyone receives a second dose (with the exception of the Janssen vaccine) and completes the series.

While there are recommended minimum timeframes for a second dose, at this time, there is no data about what the maximum interval between doses should be. Health Canada will continue to monitor this new dosing interval for safety.

Both approved COVID-19 vaccines have not listed porcine gelatin (a substance derived from pork products commonly used to stabilize vaccines) as a non-medical ingredient.

Many faith-based communities recommend or permit COVID-19 vaccination. Among these are The Canadian Muslim Covid-19 Task Force (CMTF) (external link), The Orthodox Union and Rabbinical Council of America (external PDF), and The Catholic Bishops of Alberta and the Northwest Territories (external PDF).

Taking the COVID-19 vaccine is a personal choice. If you are concerned about your faith based or cultural group’s guidance on vaccination, consult relevant leadership within your community or seek additional information before choosing to be vaccinated.

Halton Region is currently implementing Phase II of the COVID-19 Vaccine Rollout Plan. To learn who is currently eligible to get vaccinated visit our Who is currently eligible in Halton page. For information on the number of doses administered to date, see our COVID-19 Vaccination Status.

For information on the implementation of COVID-19 vaccines across Ontario, including distribution plans and identification of eligible populations, please refer to the Province’s three-phased vaccine distribution implementation plan.

At this time we are not able to provide specific timelines for when different groups will be eligible for vaccination. Timelines are dependent on supply of vaccines.

To learn who is currently eligible to get vaccinated, visit our Who is currently eligible in Halton page.

As more vaccine is made available from the Province, Halton Region will continue to work with partners to provide the vaccine to priority populations as quickly as possible.

When more groups are eligible to receive the vaccine, this will be widely communicated to the public. Visit  Who is currently eligible in Halton for more information.

The COVID-19 dashboard now includes a “Vaccinations” tab, which displays the number of doses administered in Halton to date, including doses administered by Halton Region mobile teams, and doses administered by Halton Healthcare at their site. The data will be refreshed once a week, on Fridays.

The Province determines supply prioritization and the distribution of COVID-19 vaccines. The Janssen vaccine is not currently available in Halton. There is currently no information available about when it will be available in Halton Region.

As more vaccine is made available from the Province, Halton Region will continue to work with partners to provide the vaccine to priority populations as quickly as possible.

The Province determines supply prioritization and the distribution of COVID-19 vaccines. Halton Region currently has access to Pfizer, Moderna and AstraZeneca vaccines. The vaccines available at our vaccination clinics, mobile vaccination teams, select pharmacies (external link) or physician clinics have all been approved by Health Canada.

All of the approved vaccines are safe and effective in protecting against COVID-19. It is important that you receive the COVID-19 vaccine as soon as you are eligible.

Pfizer-BioNTech, Moderna and AstraZeneca vaccines are administered in a two-dose schedule. You should complete the vaccine series with the same vaccine product.

The paper record of immunization that you receive at your first dose appointment will show which vaccine you received. Please keep this record of immunization in a safe place. You will need to bring the record of immunization with you for your second dose of vaccine.

If you consented at a COVID-19 vaccine clinic to have your information entered into the electronic data base (COVax), this information will be housed in the electronic system. Clinic staff will check your record of immunization or COVax to ensure that you receive the same vaccine product for your second dose.

If your facility is selected for a mobile clinic, your facility administrator will be contacted. Please refer to the list of facilities that are currently eligible (PDF file).

To get the latest information on Halton Region’s COVID-19 Vaccine Program including who is currently eligible, please visit halton.ca/COVID vaccines. Halton Region’s website is being updated as the program progresses, and residents are asked to check this page regularly for the latest information.

COVID-19 vaccines are administered by trained staff who follow specific steps to safely administer each dose and avoid wastage. Halton Region Public Health follows provincial guidance on the storage and handling of COVID-19 vaccines (external PDF) which includes:

• Carefully planning how many doses are required, based on the number of appointments booked at each clinic, each day;
• Following specific procedures to ensure vaccines are stored and transported correctly to planned clinics;
• Reporting any vaccine products that are damaged; and
• Allowing eligible residents (when booking their appointment) to indicate if they are interested in being notified should an earlier vaccine timeslot becomes available.
  • Residents who select this option must be able to arrive at the clinic within one hour of notification.

Staff or essential caregivers who received their first dose at Halton Healthcare will be contacted by Halton Healthcare with their second dose appointment. Staff and essential caregivers will receive their second dose 16 weeks after they receive their first dose.

If the first dose was received before March 10, Halton Healthcare will send an email with your rescheduled second dose appointment.

If the first dose was received after March 10, the second dose appointment will be booked at the same time as booking the first dose appointment. A confirmation email will be sent.

Please check your email to find your second dose appointment. Be sure to check your junk mail folder if you have not received a confirmation email. If you did not provide an email, Halton Healthcare will contact you by phone.

Please refer to the COVID-19 Vaccination in Congregate Settings, Long-Term Care and Retirement Homes in Halton Region section for more information.

Staff and essential caregivers who received their first dose at a long-term care home, retirement home or congregate living setting should check our COVID-19 Vaccination Clinics page regularly to see when they are able to book their second dose appointment. This feature is coming soon.

Staff and essential caregivers can receive their second dose 16 weeks after they received the first dose. Directors of Care will not be contacting staff and essential caregivers to book their second appointment.

No. None of the COVID-19 vaccines currently approved by Health Canada use the live virus that causes COVID-19. Vaccines “teach” the immune system to recognize and fight the virus that causes COVID-19. Sometimes this process can cause symptoms, such as pain at the injection site, fatigue and/or headaches.

It can take 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 can happen because the vaccine has not had enough time to provide protection to the body.

Vaccines authorized by Health Canada for use against COVID-19 are safe and effective.

You should delay getting the COVID-19 vaccine if you:

• Have a fever, are sick with COVID-19 symptoms, currently have COVID-19 or have been instructed to self-isolate.
• Have received any vaccine in the past 14 days.

Do not get the COVID-19 vaccine if you have an allergy to an ingredient in the vaccine or have had a previous severe reaction to this vaccine.

• Visit Health Canada’s vaccine webpages for a list of vaccine ingredients:
  • Health Canada's webpage for Pfizer-BioNTech vaccine ingredients (external link)
  • Health Canada's webpage for Moderna vaccine ingredients (external link)
  • Health Canada's webpage for AstraZeneca vaccine ingredients (external link)
  • Health Canada's webpage for Janssen vaccine ingredients (external link)

You must talk to your health care provider and before getting the COVID-19 vaccine if you:

• Are pregnant or trying to get pregnant
• Have an autoimmune condition or immunodeficiency condition and are receiving any of the following treatments:
  • stem cell therapy
  • CAR-T therapy
  • chemotherapy
  • immune checkpoint inhibitors
  • monoclonal antibodies (e.g., rituximab) and other targeted agents (e.g., CD4/6 inhibitors, PARP inhibitors etc.)

You can receive the COVID-19 vaccine but should consider speaking with your health care provider first if you:

• have an autoimmune condition or immunodeficiency condition but are not receiving any of the above treatments.
• have a history of allergic reactions not related to the mRNA vaccine
• are breastfeeding

Halton Region Public Health is not able to provide personal medical consultations. Please speak with your health care provider if you have additional questions about COVID-19 vaccines.

COVID-19 vaccines are administered by trained Public Health staff. After your vaccination, you will be asked to stay seated for 15 minutes (30 minutes for those with a history of severe allergies) to be sure you are feeling well. You will be asked to let the vaccine clinic staff know immediately if you feel unwell. Immunizing staff are trained to recognize and respond to post-vaccination reactions.

If someone experiences a reaction in the days following vaccination, they should report it to a health care professional, such as a family doctor. The reaction may or may not be caused by the vaccine. Refer to our What to Expect after Getting a COVID-19 Vaccine fact sheet (PDF file) to learn about allergic reactions and when to seek medical care.

Vaccines that have been authorized by Health Canada are safe, reliable and can help protect you, your family and our community from COVID-19. All COVID-19 vaccines were authorized by Health Canada after thorough and independent reviews determined that they meet stringent safety, efficacy and quality requirements.

As the body works to build immunity, it is common to have temporary side effects after receiving many vaccines, including the COVID-19 vaccine. In clinical trials (external link) of the Pfizer-BioNTech COVID-19 vaccine, mild to moderate side effects (such as fever, chills, tiredness and headache) were more common after receiving the second dose of the vaccine.

If you have a side effect after receiving the vaccine, contact your health care provider who will report the side effect directly to public health. Public health will keep track of the reported side effects to make sure the vaccine continues to be safe.

COVID-19 vaccines that have been approved by Health Canada are highly effective at protecting you from getting sick from COVID-19, however, they may not prevent you from becoming infected with COVID-19 or passing it onto others.

More research is being done to learn how effective the vaccines are at preventing asymptomatic (no symptoms) or mild infections even though you have been vaccinated. Until more is known about what protection the COVID-19 vaccines provide, continue to follow public health measures even after you have been vaccinated.

COVID-19 vaccines will not interfere with tests used to look for infection and will not lead to false positive test results.

People with a history of severe allergic reactions not related to vaccines or injectable medications—such as food, pet, venom, environmental, or latex allergies— should get vaccinated. People with a history of allergies to oral medications or a family history of severe allergic reactions may also get vaccinated.

People who have previously had a severe allergic reaction to any ingredient in the COVID-19 vaccine should not receive the vaccine. Visit the Health Canada web page to learn who should not receive the Pfizer-BioNTech, Moderna or AstraZeneca vaccines.

Wait at least 28 days after each dose of a COVID-19 vaccine before receiving another vaccine (that is not a COVID-19 vaccine), unless your doctor recommends otherwise.