COVID-19 (coronavirus) Featured

Your COVID-19 vaccine questions answered

woman rolls up her sleeve to get vaccine
Written by Monica Matys

On June 3, Sunnybrook hosted an Instagram live discussion on COVID-19 vaccines. Two top experts in this field – Dr. Jerome Leis, Sunnybrook’s Medical Director of Infection Prevention & Control and Natasha Salt, Director of Infection Prevention & Control – offered their expertise in addressing many questions submitted by the community. Read what they had to say about everything from side effects to updated guidelines about mixing vaccines.

If a friend or loved one is hesitant about being vaccinated against COVID-19, what can I do?

NS: It’s always important to make an educated decision about any vaccine, and the best way to do that is to direct people to credible scientific evidence. People will naturally have questions, so relying on current and balanced information will help them make an informed choice. Sharing positive stories, being a role model and underscoring that vaccines will help get us back to the many things we can’t do right now, can all help others who may be hesitant about vaccination.

How safe are COVID-19 vaccines for children and pregnant women?

JL: In the last few months, we’ve amassed a lot of safety information about these two groups from both clinical trials and observational data from multiple countries. We now know that it’s very important to vaccinate these two groups because the benefits are significant, and available vaccines have very good side effect profiles.

In May, the Canadian Society of Obstetricians and Gynaecologists reiterated their strong recommendation that all pregnant women should be vaccinated against COVID-19. For children aged 12 and older, the Pfizer-BioNTech vaccine is recommended and well tolerated, and has a safety and side effect profile similar to what is seen in adult populations.

Read Sunnybrook’s Q&A on the COVID-19 vaccine and pregnancy, breastfeeding and fertility »

What is the latest understanding around COVID-19 vaccine side effects?

JL: All COVID-19 vaccines that are approved for use in Canada have very good side effect profiles. A common side effect is a bit of soreness on the arm where the vaccine was administered. Some people may also experience flu-like symptoms, like a low-grade fever, headache and soreness in their muscles and joints, but these are usually mild and resolve within a day or two after getting the shot. While there have been reports of other side effects, the numbers are exceedingly small and should not deter people from seeking vaccination.

What are the chances there will be long-term side effects from the vaccines?

JL: We now have about seven months of data, based on the experience of administering hundreds of millions of these vaccines across the globe. When you look at the sheer number of doses given, vaccines are among the most rigorously studied for safety. While some very rare side effects have been noted, I’m extremely reassured by the safety profiles of all the vaccines available to Canadians. I think it’s very unlikely that the emergence of longer-term side effects is a risk.

Can COVID-19 vaccines affect the menstrual cycle?

NS: There have been some reports of women who have experienced changes to their menstrual cycle following vaccination, but any possible effects appear to be short-term, so lasting about one month. As this is a question that is currently being studied, the hope is to have more information to share in the near future.

What are your thoughts on mixing vaccines, in light of recently updated guidelines from the National Advisory Committee on Immunization (NACI)?

JL: Mixing vaccines for other conditions is not a new concept, and there is lot of science showing that most vaccines are interchangeable. While we didn’t initially have that information for COVID-19 vaccines, it was just a matter of collecting the data to be able to now confirm the safety of this practice.

We’re at a very critical juncture in Canada because there are new and emerging variants, most notably the Delta variant, and many people are still awaiting their second dose. The good news is people who have had two doses of the vaccine appear to be highly protected against all these new variants. Now we have the guidance from NACI that the science supports mixing and matching different vaccines for their second dose. In short, the best vaccine to get is the one you are being offered.

Will everyone need a COVID-19 booster shot each year?

JL: Receiving vaccines is a normal and recommended practice throughout our lifespan. Depending on the infection, sometimes boosters are needed to maintain a good level of protection. It’s widely expected that we’ll need to get a periodic booster for COVID-19, but the timelines haven’t been confirmed.

If someone has been fully vaccinated, do they still need to follow safety protocols like wearing a mask and physical distancing?

NS: The day will come when we can gather in groups and not wear masks, but we have to be really careful in how we scale these types of restrictions back. That will require herd immunity, meaning when a certain level of the population has either been exposed to COVID-19 or have been vaccinated to stop person-to-person spread of the virus. We’re not there yet.

While we’re starting to see some public health measures being relaxed, we could find ourselves in a fourth wave if things move too quickly. So for now, even if you’ve been fully vaccinated, please continue to follow recommended safety protocols.

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About the author

Monica Matys

Monica Matys is a Communications Advisor at Sunnybrook.

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