COVID-19 vaccine 101: sorting facts from fears

·6 min read

As the COVID-19 vaccine program rolls out across the province and country, polls indicate most Canadians intend to get immunized.

For the minority who remain uncertain – safety and effectiveness are cited as primary concerns – we gathered the most common questions and turned to scientists, experts, and reputable sources for answers.

Do vaccines work?

Yes. Every year, vaccines prevent people around the world from contracting dozens of infectious diseases and their variants, including, polio, hepatitis, measles, tetanus, tuberculosis and others.

According to the World Health Organization, over the past century, billions of vaccinations have been administered globally, preventing 2 to 3 million deaths annually.

The Pfizer-BioNTech and Moderna COVID-19 vaccines are both about 95 per cent effective at preventing symptoms, serious illness, and the development of COVID-19. Seasonal influenza vaccines typically have between a 40 to 60 per cent effectiveness.

“When someone receives a vaccine, it stimulates our own body's immune system to produce antibodies to that antigen, that protein,” said Provincial Health Officer Dr. Bonnie Henry.

The vaccine was developed so fast, is it safe?

“The global community of scientists have collaborated in ways we never experienced before, with a single purpose in mind to develop a safe and effective vaccine for the world,” Henry said. “The greatest brains around the world were put to this process and to this task.”

Each vaccine manufacturer had to demonstrate clear and substantial scientific and clinical evidence that the vaccines are safe, effective, and manufactured to the highest quality, she said.

COVID-19 vaccine clinical trial results published in the New England Journal of Medicine on Dec. 10 indicated similar safety levels to other commonly administered virus vaccines.

“Health Canada, and other regulators around the world, set the bar high to ensure that any vaccines that came out of this process met those standards, that they were safe, that they worked, and that they were quality vaccine,” Henry said.

How long will I be immune after I get vaccinated?

Immunity varies for different vaccines. Some provide immunity for years, some for a lifetime, and others, like influenza, for months.

So far, the immunity levels have held steady for people who received the Pfizer and Moderna vaccines beginning with clinical trials last fall.

“It's at least three to four months, which is good news,” said Henry.

We won’t know the full length of immunity until more time passes.

Can I still spread the virus after getting vaccinated?

It’s not yet known whether people can shed virus after being immunized. Vaccines are effective tools against the spread of communicable disease. The COVID-19 vaccine will slow the spread of the virus by reducing the number of people who contract the disease and suffer severe illness, but it won’t eliminate the virus.

“This disease appeared a year ago, and we've made so much progress in terms of knowledge about this disease in a year it is incredible,” said Dr. Caroline Quach-Thanh, a pediatric infectious disease physician who holds the Canadian Research Chair in Infection Prevention at the University of Montreal and is also Chair of the National Advisory Committee on Immunization (NACI). “So yes, there are things we don't know, and I think it is important to acknowledge we don't know. But I don't think that that should stop people from getting vaccinated.”

Will I still have to wear a mask after I’ve been immunized?

Yes. While the vaccine is about 95 per cent effective at preventing the development of COVID-19, it’s not yet known if a vaccinated person can, subsequently, be an asymptomatic spreader of the virus, just as it’s unknown whether a person can be reinfected after contracting COVID-19 naturally.

“That's why, it's still really important that everybody continues to wear masks, to clean their hands regularly, to take those measures that we know prevent transmission to droplets between people,” said Henry.

COVID-19 isn’t as serious as public health is saying – why don’t we just let the disease die out naturally?

“The risk of complication and death is just too high to let it run its course,” said Quach-Thanh.

In Canada, as of Jan. 20, more than 725,000 people had been diagnosed with COVID-19 and 18,462 Canadians had died from the disease (including 1,004 people in B.C.) over the duration of the pandemic. Worldwide, more than 2 million people had died and more than 97 million had been diagnosed with COVID-19.

By that date in the U.S., 24.4 million Americans had been diagnosed with COVID-19 and 405,000 people had died of it.

Virginia Commonwealth University researchers called the COVID-19 mortality rate in the U.S. ‘calamitous,’ comparing it to having 15 Airbus jetliners carrying 150 people crash every day.

Will the government make vaccinations mandatory?

Neither Federal, nor British Columbian government officials have suggested mandating vaccinations.

According to a recent Ipsos poll for Global News, however, 64 per cent of Canadians support mandatory vaccination, while 72 per cent said they would get vaccinated as soon as they could, including 88 per cent of British Columbians polled.

Are the vaccine side effects worse than the disease?

In Canada, side effects so far have been similar to mild flu symptoms, sometimes intensifying after the second dose, Quach-Thanh said.

Common side effects include pain at the site of injection, body chills, fatigue or feeling feverish. These indicate a healthy immune system response and tend to occur within one to three days of inoculation, resolving within hours or a few weeks, according to Health Canada.

As of Jan. 20, almost 700,000 COVID-19 shots had been administered in Canada, including almost 98,125 in B.C. By the same date, more than 55 million COVID-19 vaccine shots had been administered worldwide, according to Bloomberg’s vaccine tracker.

“If something happens, we will hear about it, because the company has to report it to Canada,” said Quach-Thanh.

Pregnant women, people with severe autoimmune conditions such as cancer patients, and people who have previously had severe allergic reactions to vaccines should consult a health practitioner before getting vaccinated.

Can I get COVID-19 from the vaccine?

“There is absolutely no way you can get COVID-19 from the vaccine. It is not possible,” said Dean Blumberg, chief of pediatric infectious diseases at University of California Davis Children’s Hospital in the school’s health bulletin. “None of the vaccines being developed use the live virus. There is nothing in the vaccine that could cause COVID-19.”

Should I get vaccinated?

“I think that if we are able to stop this pandemic, it will be due to the vaccine, otherwise, it will strain our lives like this for many, many, many years to come,” said Quach-Thanh.

“The Pfizer and the Moderna vaccines are very effective at preventing symptoms, especially severe symptoms, and preventing people from hospitalization and dying from COVID,” said Henry.

For more information, visit: or / @FranYanor

Fran Yanor, Local Journalism Initiative Reporter, The Rocky Mountain Goat