Ask a Scientist: Should I consider getting vaccinated against COVID-19?

Should I consider getting vaccinated against COVID-19?

The answer to that question is overwhelmingly YES.

By getting vaccinated, you are helping to protect yourself and likely those around you from the virus that causes COVID-19.

But also, getting majority of people vaccinated is our best shot at beating this pandemic and going back to more normal life.

So let's start with how these vaccines help protect YOU from the virus.

Vaccines help your body develop immunity against a specific pathogen, like a virus or some bacteria.

• Essentially, a vaccine is like a 'practice round' or training exercise for your immune system: it gives your body the opportunity to build up its defenses against a pathogen without actually being exposed to the pathogen itself.
• That's the huge benefit of vaccination – you get the protection without the disease. It's also what makes vaccination a safer strategy than trying to gain some immunity through real infection, as infections can become severe or lead to long-term health consequences.
• In the case of the approved vaccines against COVID-19, the vaccines stimulate your immune system to develop antibodies and other protective factors that can help recognize and fight the virus that causes the disease.

It's like the vaccine is doing the prep work to train your immune system to deal with the real virus if you get exposed to it later on.

The immunity you develop following vaccination is extremely specific, and there is no food you can eat, no product you can buy, and no exercise you can do to achieve the same effect.

Decades of research in the areas of infectious disease and the body's immune response have made this very clear: Only a vaccine works like a vaccine.

I say that because being fit or otherwise in good health is not the same as equipping your immune system to fight a specific virus.

• And no example highlights this more clearly than the numerous cases of even elite athletes becoming severely ill with COVID-19.
• These are people considered to be in excellent health before they became infected, but some are continuing to face debilitating symptoms long afterward.

That's why, even if you're young or feel that you are in a low-risk group, getting vaccinated is still the best protection you can give yourself.

Now, let's also talk about how getting vaccinated could help protect those around you.

It's worth noting that a very small percentage of people are not good candidates for vaccination, mostly due to an allergy to a specific component of the vaccine or some health conditions. These are things that you can talk to your health care provider about if you have concerns.

There are others who simply might not be able to produce a robust immune response after receiving the vaccine.

• People on immunosuppressant drugs—such as those who have had organ transplants, for example—and people who are otherwise immunocompromised aren't likely to be as protected by vaccination, at least not at that individual level.

This is where the concept of herd immunity becomes important.

• We talk about the virus that causes COVID-19 as being new (or novel) to humans.
• When an infectious pathogen is new like that, no one has pre-existing immunity to it. Everyone is susceptible to infection if they're exposed.
• This allows it to spread through the community, from person to person.
• And it can continue like this because people can continue to be infected.
• But if the vast majority of a community has some immunity against infection, then the pathogen won't have as many susceptible hosts available. That means it won't be able to spread as easily.
• And reducing the spread of infection is what makes things safer for the people who are not able to develop immunity on their own. They get protected by the herd, essentially, because other people's immunity disrupts the spread and ensures that there's less of the pathogen circulating in the community.

To be clear, studies are ongoing and there is a lot of discussion taking place right now about how much vaccination coverage we'll need against COVID-19 to achieve what's known as a herd immunity threshold.

These studies and discussions will take into account factors like variants of concern, so you may even see some of the projections change over time.

But overall, the thing to remember is that vaccinating as many Canadians as possible will give us the best shot at limiting the spread of COVID-19.

In summary:

• Getting vaccinated against COVID-19 is the best way to protect yourself from severe illness and to help protect your community.
• Vaccination is one of the greatest tools we have against this pandemic, but it's a collective effort.
• That's why I hope you'll grab a vaccine appointment when it's your turn, like I did.
• And if you have questions, don't hesitate to talk to your health care provider.

Special thanks to

Dr. Charu Kaushic

Scientific Director, CIHR Institute of Infection and Immunity
Full Professor, Department of Medicine, McMaster University
Chair, Global Research Collaboration for Infectious Disease Preparedness (GLOPID-R)