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Southlake expert answers your questions about COVID-19 vaccines

How does it work? Can I still spread the virus after I get a dose? What if I have allergies? You asked, so NewmarketToday spoke to the physician co-lead of our Newmarket hospital's vaccine management committee for some straight answers on the vaccines
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Dr. Charmaine van Schaik serves as the co-lead of the vaccine management committee at Southlake Regional Health Centre.

NewmarketToday spoke with Dr. Charmaine van Schaik, who serves as the co-lead of the vaccine management committee at Southlake Regional Health Centre and is the physician leader for maternal child programs, to get answers to your questions about the COVID-19 vaccines. 

NT: A lot of people are wondering how exactly do these vaccines work. Are they similar to influenza vaccines?

van Schaik: No, the two vaccines that we have (Pfizer and Moderna) are different from traditional influenza vaccines. They are both what we call mRNA  —Messenger Ribonucleic Acid — vaccines and they are very different.

In simple terms, the mRNA vaccines introduce the actual spike protein mRNA into the body, so it runs around the system and gets flagged as foreign, so the body will recognize it if you get infected down the road and fight against it.

NT: This is a new kind of vaccine, is it not?

van Schaik: Over the past 10 years or so there have been numerous mRNA vaccines developed that have seen some clinical use, but not in a mass way like this. There have been a lot of questions about whether they are safe because they went through clinical trials so quickly. But the benefit of them is that a lot of the front-end work of developing them can be done much quicker to get to the research and trials that follow the standard timeline. 

NT: So that means they are safe, despite how quickly they were developed?

van Schaik: Absolutely. The drug companies have put out information about their trials, and we are reading all that direct research. We are also finding clinical research that is founded in science and not just the summaries or what the drug companies say because, obviously, they would have some biases toward their own products. So we are going back to the primary research so that we are making good decisions about what we are advocating for. 

I've had my vaccine, and I would advocate for all my friends and family to get one. There are still a lot of things we will learn as they come out. Such as, we don't know how long it protects you for, or whether you will need an annual booster dose.

NT: What happens to the mRNA it introduces into your body? Can it affect your cells after it has done its work?

van Schaik: We have seen a lot of discussion in public about how difficult it is to transport these vaccines and how we need to use these special freezers. That's because mRNA is so unstable, it doesn't last very long. It eventually breaks down and disintegrates. But during that process, it creates the spike proteins, which are the key to creating antibodies.

NT: Can you still get or spread COVID-19 if you have been vaccinated?

van Schaik: We don't know 100 per cent on that. We have certainly been shown from the research that it decreases the severity of illness. When I say that, I mean severe disease where you end up in the hospital or the ICU. Plus, less severe disease where you might need to take days off work, spend time in bed, etc. 

The bigger question that we don't know about is whether it prevents you from spreading the disease. Even if it modifies the severity of illness, or prevents symptoms, we don't know if we are also not infectious.

NT: Why are there two doses of the vaccine spaced three weeks apart? What happens in between doses?

van Schaik: It takes a bit of time for your body to adapt after the vaccine has been introduced into it. If you give them too close together, there may not have been enough time to maximize the body's response, so that's why we have that distance in time.

The first shot raises the alarm, and the second shot builds on that and takes it to a new level. 

NT: Are there any side effects of the vaccines that we are aware of, and should you get medical help if you experience them?

van Schaik: There are a variety of side effects, most of them mild. Like most other vaccines, it can be something as simple as pain and swelling at the vaccination site. Because you are pushing a foreign substance into your muscle, so the muscle can yell back 'ouch, I'm sore,' and you can get that local tenderness and swelling.

As your body mounts your immune response, it can vary and isn't reflective of whether you have mounted a good or poor response. The inflammatory and immune systems can cause things like fever, muscle aches, chills — the sort of stuff that people associate with the flu. That doesn't mean you got sick from the vaccine, you can't get sick from these vaccines, there's no active virus. 

As for whether you should get medical attention, the advice is essentially no. If your symptoms resolve within 48 hours, you don't need to be concerned.

The exception is if you have respiratory symptoms such as shortness of breath or a cough, that's not a side effect of the vaccine, and you need to think about possible COVID-19 infection and getting tested. 

NT: Are there any allergies that would prevent people from getting the vaccine?

van Schaik: The only allergy complications for the vaccines are if you have an allergy to one of the vaccine ingredients. The main one is polyethylene glycol, which is found in a lot of medications. 

Polyethylene glycol is found in Tylenol, so if you have used Tylenol on a regular basis and have never had a problem, you don't have an allergy to polyethylene glycol.

NT: How about pre-existing conditions?

van Schaik: The general rule of thumb is that if you have significant health issues, talk with the doctor who cares for you. Sometimes that's your family doctor, sometimes it's your specialist. But for the most part, there are no strong indications for illnesses that mean you should not (get the vaccine,) but there are exceptions to every rule. 

NT: Do we know if the vaccine can have bad reactions with anti-depressants or anti-psychotic medications?

van Schaik: Not specifically. Everyone has different medical histories in that regard. If you are on a variety of medications or are asking for new medications, my advice would be to talk to your doctor if you have a concern. 

Most specialists I've talked to and most things I've read say that's not a factor. The risk of COVID-19 is higher than the chance of medications causing a problem, which most often would be making your immune response to the vaccine sub-optimal.

NT: Have there been any really bad reactions to the vaccine so far?

van Schaik: I've worked at the vaccination centre, and we've had a few people who have had reactions, but nothing severe. Most have not required to go to hospital. 

NT: The public health unit has indicated that children under 16 are not likely to get vaccinated for many months. Why is that?

van Schaik: The simple answer to that is that none of the studies have been done on kids, all of them have been done on people aged 16 or above.
Most studies won't extrapolate (their findings) for kids for obvious reasons. Understanding how the vaccine will affect their bodies and systems is really important.  

As more vaccines are developed, that's where we will find those opportunities. Some studies are looking at ages 12 and up, and they will continue to go down in ages as more vaccines are developed and tested. Most of the research has been targeted at 16 and above because it's been recognized that adults and older people are more affected as a population and with severity.

NT: Do we have any idea when there may be a vaccine for children available?

van Schaik: Not that I am aware of. 

NT: How long does the protection from the vaccine last once you get it?

van Schaik: That's what is currently being looked at. A lot of research trials focused on the dosing, but what the data are capturing now is from people after they have been vaccinated on what their response is and how long it lasts.

Some say it's three months, some say longer, but nobody has had the time since the pandemic started to go beyond that. So we really don't know.

NT: Should people keep wearing face masks once they are vaccinated?

van Schaik: Yes, we at the hospital still do.  We are developing our immune response once we get vaccinated, but that doesn't mean we are 100 per cent immune to the illness, and we still need to protect against potentially spreading the illness.

NT: So should vaccinated people still wear masks when visiting friends and family?

van Schaik:  Yes. Until more people are vaccinated, and we establish some form of herd immunity, and we have a better understanding of how it affects the spread of the virus, you still need to keep practising public health guidelines. 

NT: Will people get proof of vaccination, and what can it be used for?

van Schaik: Yes, when people get the vaccine, they will get proof of vaccination, but it's not a formal document in the sense that it acts as a passport in any way. All it says is that you got the vaccine, when you're supposed to get your next dose, etc. All of that will be in the electronic system as well.

NT: Is there anything else you think the public should know?

van Schaik: I would just like to advocate that people go get the vaccine when they can. Vaccine hesitancy is a great concern, and we are asking people to make informed decisions. So if you have concerns, try to find good information or ask health professionals. We're not biased, we just want to inform people.

It can be hard to just go on the internet to find quality information because, even in the medical literature, you have to decipher a lot of varying opinions. I just want people to make the decision for themselves, but one grounded in fact. 

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Alan S. Hale

About the Author: Alan S. Hale

Alan S. Hale is a reporter for
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