What are the coronavirus variants and how should we respond to them? Your COVID-19 questions answered

CBC readers want to know about the coronavirus variants causing concern around the globe. Here's what the experts have to say.

Questions from readers include if we need better masks and more physical distancing

Laboratory technicians wearing protective equipment work on the genome sequencing of the SARS-CoV-2 virus and its variants at the Pasteur Institute in Paris on Jan. 21. (Christophe Archambault/AFP/Getty Images)

We're answering your questions about the pandemic. Send yours to, and we'll answer as many as we can. We publish a selection of answers online and also put some questions to the experts during The National and on CBC News Network. So far, we've received almost 67,000 emails from all corners of the country.

Canada's chief public health officer, Dr. Theresa Tam, warned Wednesday that variant strains of the coronavirus had been found in eight provinces, and that they could quickly reverse the gains the country has made in recent weeks in the battle against COVID-19.

At least two of three variants of concern are spreading in Canada, in some cases with no known link to travel, and have already led to devastating outbreaks in long-term care homes.

Here's a look at some of the most common questions Canadians have about the variants.

What is it about the new coronavirus variants that makes them more transmissible?

As a virus infects people, it can mutate as it makes copies of itself. Some mutations can be harmful to a virus, causing it to die out. Others can offer an advantage and help it spread.

"Not every mutation is created equal," Mary Petrone, who studies infectious diseases at Yale University, told The Associated Press. "The virus is going to get lucky now and again."

There are many variants circulating around the world, but health experts are primarily concerned with the emergence of three

  • B117, first discovered in the U.K., which has "a large number" of mutations, according to the U.S. Centers for Disease Control and Prevention (CDC).
  • B1351, first discovered in South Africa, which shares some of the same mutations as B117.
  • P1, which was first discovered in Japan, in four travellers who had been in Brazil. 

Dr. Eric Topol, a U.S. physician, scientist and clinical trials expert who heads the Scripps Research Translational Institute in California, told CBC News in January that the variant first found in the U.K. exhibits changes in the spike protein — a key component of how the coronavirus binds to human cells.

He said those changes are likely behind its higher transmission, with the altered spike protein potentially allowing the coronavirus to infect cells more easily. The other two variants of concern also have changes to the spike protein.

WATCH | Dr. Bonnie Henry 'confident' variant transmission isn't widespread:

Dr. Bonnie Henry 'confident' variant transmission isn't widespread

2 years ago
Duration 1:15
B.C.'s provincial health officer says the province is aiming to control the spread of more infectious coronavirus variants over the next few weeks as it ramps up vaccinations.

If the variants are more contagious, do we need to distance more?

Ashleigh Tuite, an infectious diseases epidemiologist and assistant professor at the University of Toronto's Dalla Lana School of Public Health, noted to CBC's Adam Miller earlier this month that the 15-minute exposure time and two-metre distance guidelines from the federal government are "arbitrary." 

"The new variants, I think, provide us with a reason to re-evaluate those rules and I think that's something that hasn't necessarily been well-communicated to the public," she said. "There's nothing magical about that distance that was based on science, that's based on sort of what we know about how airborne pathogens are spread. But I think the science has evolved, or at least our thinking has evolved." 

Erring on the side of caution makes sense, she said.

Dr. Lucas Castellani, an infectious diseases specialist at Sault Area Hospital, told CBC News Network on Feb. 2 that there's no set distance the virus can travel, regardless of variants.

"We know it potentially can go farther and there are a lot of factors involved," he said in regards to a question about smoking or vaping during the pandemic. "How heavy the person has been breathing, how good the ventilation is in the room or the space you're in."

At the same time, Castellani said he suspected based on the mutations that it's not a case of the virus hanging in the air longer or travelling farther.

"Based on the type of mutations they have, it is unlikely that those are the types of characteristics that are leading to the change that we're seeing," he said.

WATCH | With COVID-19 variants, questions of whether guidelines go far enough:

With COVID-19 variants, questions of whether guidelines go far enough

2 years ago
Duration 2:03
The spread of the highly transmissible COVID-19 variant first found in the U.K. has some Canadian doctors wondering if our current distancing recommendations are enough.

Should we be wearing better masks?

Yes. Experts say we should consider finding better quality masks, wearing two at a time and/or wearing them more often.

In fact, the CDC released new guidance on Wednesday that said a lab experiment had found two masks meant double the protection.

The CDC said a cloth mask worn over a surgical mask can tighten the gaps around the mask's edges that can let virus particles in.

The researchers found that wearing one mask — surgical or cloth — blocked around 40 per cent of the particles coming in during an experiment. When a cloth mask was worn on top of a surgical mask, about 80 per cent were blocked.

WATCH | COVID variants can cause cases to increase exponentially, Ontario health official says:

COVID variants can cause cases to increase exponentially: Ontario health official

2 years ago
Duration 7:51
There is obvious community transmission of COVID-19 variants, according to York Region Medical Officer of Health Dr. Karim Kurji, who says the virus needs to be contained as it has the capacity to increase case numbers exponentially.

Canada recommends the use of three-layer non-medical masks with a filter layer to prevent the spread of the virus, but has not updated its recommendations since November, before the emergence of the new variants. 

Dr. Zain Chagla, an infectious diseases physician at St. Joseph's Healthcare Hamilton, told CBC News that while three-layer non-medical masks are a good "minimum standard," Canadians should opt for masks that offer better protection whenever possible.

Those include surgical masks, which are a step below N95s and KN95s and come in three different filtration levels determined by the American Society for Testing and Materials (ASTM).

"When I go to the grocery store now, I wear my very best mask," said Linsey Marr, one of the top aerosol scientists in the world and an expert on the airborne transmission of viruses at Virginia Tech. "Before I was wearing an OK mask that was comfortable and easy."

She said a cloth mask can "easily filter out half of particles, maybe more, but we're at the point where we need better performance." 

WATCH | Must detect variant COVID-19 cases quickly to stop spread, immunologist says:

Must detect variant COVID-19 cases quickly to stop spread, immunologist says

2 years ago
Duration 3:22
In order to limit the spread of COVID-19 variants, cases must be detected quickly to ensure isolation occurs, says microbiologist and immunologist Craig Jenne.

Erin Bromage, a biology professor and immunologist at the University of Massachusetts, Dartmouth, who studies infectious diseases, said a tight-fitting mask is more important than ever due to the emergence of variants.

"It's not that double-masking provides extra protection if the mask was fitting well," he said. "Double-masking helps the mask that is closest to your skin fit more snugly, meaning more air goes through that mask."

If you're already wearing a high-quality mask that fits well, with air going through the material rather than out the sides, Bromage said there's no extra benefit in throwing an extra mask on top. 

He recommends looking at yourself in the mirror before you go out to make sure your mask isn't too loose fitting.

"I really want people to look at them and think, is all the air going through the material? And if it's not, work out a way to do that," he said. "And that may be putting a second mask on or finding a different mask that fits their face." 

WATCH | Simple hacks to make your face mask more effective:

Simple hacks to make your face mask more effective

2 years ago
Duration 2:38
Canadian respirologist Dr. Samir Gupta explains the latest COVID-19 mask recommendations and demonstrates simple hacks to make yours more effective.

Are the variants more deadly?

It's possible. There is some evidence the variant first found in the U.K. carries a higher risk of death than the original strain, the British government's chief scientific adviser said in January.

"The verdict is still slightly out but theoretically, yes, it's possible," Castellani, the infectious diseases specialist at Sault Area Hospital, told CBC News. "And unfortunately that's the way viruses work and the way mutations potentially catch up with us."

WATCH | The race between COVID-19 vaccines and variants continues despite concern about efficacy:

The race between COVID-19 vaccines and variants continues despite concern about efficacy

2 years ago
Duration 2:02
South Africa has halted its rollout of the AstraZeneca COVID-19 vaccine after a study showed it offered minimal protection against mild infection from a variant spreading there. While experts say it's cause for concern, they say vaccines can be reconfigured to protect against mutations.

Is it possible to be re-infected from any of the variants?

"Yes, it is possible to be re-infected," Castellani said on Tuesday. "We're seeing that in some parts of the world, in particular South Africa, that some individuals are in fact being re-infected with the virus. It's felt that once you get the immunity from the virus it may last for some time, but not everyone's will last the same as the next person."

Dr. James Hamblin, a Yale University public health policy lecturer and a writer with the Atlantic, told CBC's Front  Burner that a raging outbreak in the Brazilian city of Manaus also pointed toward re-infection.

"It's been very tragic there: places running out of oxygen, people being buried in mass graves," he said. 

The city was hit so hard by the coronavirus in the spring that researchers estimated that 76 per cent of the population had been infected, which makes the severity of this recent outbreak unexpected and concerning.

Hamblin said the leading theory is that it's a combination of fading immunity given that the first surge in Manaus was about nine months ago, along with the dangers of the P1 variant. 

The variant "shares a mutation that the South Africa variant also has, which gives it a propensity to evade immune responses."

Does giving one dose of the vaccine and waiting beyond recommended days for the second dose help the virus adapt?

"It can," said Dr. Isaac Bogoch, a Toronto-based infectious diseases specialist and member of Ontario's vaccine task force, in an interview with CBC News Network on Monday. 

He said the concern is if you only give one dose of a two-dose vaccine regimen you can create an environment that allows the virus to "selectively evade that protection, and that's certainly a theoretical concern."

However, he said, in Canada most people will get the second dose on the optimum day (21 or 28, depending on the vaccine), and if not, within the recommended 42 days. 

Is there concern that 14 days is not long enough to quarantine and protect others from virus variants?

Bogoch said that while the variants of concern may have greater transmissibility or the ability to evade vaccination more readily, the incubation time or duration of the illness hasn't changed. 

"Obviously we have to be open-minded, we have to be humble, there might be new data that results in a change in policy, but I think the 14-day [quarantine] should be fine for now."

However, Alberta did strengthen its quarantine rules, because the variants are more easily spread through households.

"If cases choose to stay home during their isolation periods [rather than other isolation options], their household contacts will need to stay at home as well in quarantine, until 14 days have passed from the end of the case's isolation period, for a total of 24 days," said Dr. Deena Hinshaw, Alberta's chief medical officer of health, during a news conference last week.

"Given how easily this variant is spreading in homes, this enhancement is necessary to prevent spread in the community."

WATCH | AstraZeneca vaccine can be used against coronavirus variant first found in South Africa, says WHO:

AstraZeneca vaccine can be used against coronavirus variant first found in South Africa, says WHO

2 years ago
Duration 2:10
WHO's expert advisory group says there is a 'plausible expectation' that the AstraZeneca vaccine will be effective against severe disease from the coronavirus variant found in South Africa, despite a small study that prompted concerns.

We're answering your questions every night on The National. Last night, we asked our experts about the impact of stress — nearly one year into the pandemic.

The impact of stress, a year into the COVID-19 pandemic

2 years ago
Duration 6:11
A physician and psychiatrist talk about the impact that stress is having on mental and physical health a year into the COVID-19 pandemic and what the longer-term effects might be.

With files from CP, AP, CBC's Adam Miller and Front Burner


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