From mu to C.1.2, here are the latest coronavirus variants scientists are watching closely

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So why do these new variants matter, what are they capable of, and how much should Canadians care?

Right now, the highly-contagious delta variant — deemed a variant of concern by the WHO back in May — is dominating Canada’s COVID-19 cases, making up more than 90 per cent of reported recent infections according to federal data.

But that doesn’t mean other emerging variants don’t warrant close observation. 

“Looking at this virus, it’s obvious that we will have new variants,” said Alyson Kelvin, a virologist at the Vaccine and Infectious Disease Organization (VIDO) at the University of Saskatchewan. 

“What we need to do is to be ready for identifying cases … as well as other variants that are inevitably going to start emerging around the world.” 

Here’s what Canadians need to know:

What is the B.1.621 — or mu — variant?

B.1.621 is the latest variant of interest, according to the WHO, and was given the designation — and a catchier Greek alphabet-based name, “mu” — on August 30.

“The mu variant has a constellation of mutations that indicate potential properties of immune escape,” reads the WHO’s latest weekly epidemiological update.

That means those with some level of immunity to earlier strains, either by previous infection or vaccination, might be susceptible to infection from mu — but that’s only according to preliminary data and “needs to be confirmed by further studies,” the update continued.

The variant was first detected in Colombia back in January, and since then, the country has experienced hundreds of cases and the variant has also been reported in 39 other countries around the world.

Here in Canada, it’s barely making a splash: Mu cases have been reported for weeks, but so far, the variant hasn’t made up more than three per cent of cases in any given week and recently totalled just 0.3 per cent — though federal data since mid-July is still accumulating and could change.

What is the C.1.2 variant?

The variant C.1.2 isn’t deemed a variant of interest or concern yet by the WHO, but researchers are pushing the organization to watch it closely.

A team of scientists from South Africa detected the new variant, which was first observed in May and has since spread to seven other countries in Africa, Europe, Asia and Oceania, according to a preprint study that hasn’t yet been peer-reviewed.

“It’s still not clear where this came from,” noted Dr. Zain Chagla, an infectious diseases specialist with McMaster University in Hamilton. “It was first identified in South Africa but people need to know that South Africa has actually quite good sequencing networks and so it may not be the origin.”

Richard Lessells, an infectious disease specialist and one of the authors of the research on C.1.2, told Reuters the variant may have even more immune-evasion properties than delta, based on its pattern of mutations, and that the findings had been flagged to the WHO.

However, it’s not known yet if the variant is actually more contagious, or more capable of evading the immunity provided by either vaccines or a prior coronavirus infection.

“These things need time to see,” Chagla said. “Delta is incredibly fit, and incredibly virulent and replaces [other strains] aggressively. We still haven’t seen suggestions of this yet [with C.1.2].” 

WATCH | Herd immunity harder to achieve thanks to variants, says government scientist:

Herd immunity harder to achieve now because of new variants, says government scientist

Speaking with Power & Politics, Chief Science Advisor of Canada Mona Nemer says that collective immunity is a moving target but will be difficult to achieve due to the emergence of new COVID variants. 2:02

How worried should Canadians be right now?

Given that delta makes up the lion’s share of Canada’s COVID-19 cases and there’s still much we don’t know about mu or C.1.2 — concerns over emerging variants need to be put into context.

Chagla said it’s important to keep studying and monitoring the C.1.2 variant, but “there’s no need for panic yet.”

There has been an increased spread of C.1.2, and it’s a rising percentage of sequenced cases in various countries outside of South Africa, Chagla said, but nothing on the scale of delta and it remains to be seen if we’ll experience more global spread. 

“It’s still not clear whether or not that just means there’s a lot of local spread amongst particular groups that just seems to be over-represented — or if it’s a legitimate growth pattern,” he added.

“We still don’t know, if you put things in the same pool, whether or not delta is going to be much more virulent.” 

Chagla says that much like other variants that have emerged over the course of the pandemic — including variants of concern like alpha, beta, lambda and, now, mu — they could either be overtaken by delta or “burn themselves out over time.” 

“Right now, it seems that there aren’t a large number of cases for [C.1.2],” Kelvin said. “But now that we have this identified, then surveillance centres around the world can start to determine, are they seeing numbers of these cases as well?” 

To figure out how often variant cases are appearing here, the Public Health Agency of Canada works with the provinces, territories, and the Canadian COVID Genomics Network (CanCOGen) to sequence a percentage of all positive COVID-19 test results.

Sequencing reveals the genetic code of the virus, showing which variant was involved in a specific case of COVID-19, and those results are reported each week. 

Dr. Catalina Lopez-Correa, chief scientific officer at Genome Canada and executive director of CanCOGen, said there is still “very little data” from the real world on the increased threat of the variant. 

“The key message for Canada is that we are actively monitoring for this variant,” she said. “It has not been detected yet here and we are also actively following up all the data that is published and shared across the globe.” 

Why do new variants matter in the global fight against COVID-19?

New variants have emerged throughout the pandemic in populations with low vaccine coverage that have been hit hard by unchecked COVID-19 transmission — including India, South America and Africa — and experts say this trend is likely to continue until more of the world is vaccinated.

“This is an incredibly big reminder — even if this is a false alarm — of what global vaccine equity means,” said Chagla. 

“Many of us starting to see the delta wave in Sub-Saharan Africa were very, very worried about what could come of that.”

WATCH | WHO calls for vaccine equity:

WHO comments on need for global COVID-19 vaccine equity

People in wealthier countries are getting vaccinated at a much faster rate than those in poorer countries despite efforts by the World Health Organization and the international community to make COVID-19 vaccine accessibility equitable around the world. 2:04

Chagla says the region has low vaccination levels, poor quality healthcare systems and a large population of immunocompromised individuals, with rates of HIV in some countries as high as 15 to 20 per cent of the adult population.

“That was kind of a mixing pot of bad scenarios to lead to the development of a variant … so I don’t think we can be surprised to see that something seems to have shown up,” he said. 

“And we kind of just watch it happen in that sense, and we continue to watch it happen.”

It’s also clear these variants don’t stay put.

Even if they emerge in one area of the world, cases later appear elsewhere — meaning other countries, including Canada, are eventually impacted yet again by this ever-evolving virus.