Alberta is at another tipping point in the COVID-19 pandemic.
Chief Medical Officer of Health Dr. Deena Hinshaw says some parts of the province are at risk of seeing the B117 variant become the dominant strain of the virus.
If other countries are any indication, experts warn it’s not a matter of if, it’s a matter of when.
“Once we start seeing transmission of B117 in the community, I would expect that that would gradually become the dominant strain because it is more transmissible,” said Dr. Stephanie Smith, director of infection prevention and control at the University of Alberta Hospital.
It’s an expectation reflected in the current numbers.
The province broke a record for daily new B117 cases on Wednesday with 201, which broke Tuesday’s record of 195, which broke Sunday’s record of 184. The variant now makes up about one in five active cases, and rising.
Here’s more information about B117, the variant first detected in the U.K., and what it means for the province.
Are the vaccines effective against B117?
Let’s start with the good news: Yes, research shows the vaccines are effective against the B117 variant.
Moderna’s initial findings released in January found no significant impact on the vaccine’s power to neutralize the variant when compared to the wild type virus, another way of saying the original strain.
Same goes for Pfizer-BioNTech and Oxford-AstraZeneca, studies show. A preprint study led by researchers from Public Health England and posted this month found both vaccines performed well against the variant.
Is this variant more contagious?
Yes, significantly more contagious than the original strain, according to a mounting pile of evidence.
A research article published in the journal Science found the variant had between a 43 per cent and 90 per cent higher reproduction number, with similar ranges observed in Denmark, Switzerland and the U.S.
A separate pre-print study, meaning it had yet to go through the rigorous peer review of a scholarly journal, also found it to be more contagious. The researchers from the Imperial College in the U.K. found B117 boosted the reproduction number by between 40 per cent and 70 per cent.
If the reproduction number is at 1, an infected person will infect an average of one other person.
But what happens if the reproduction number increases by 50 per cent, for example, to 1.5? A group of 100 people would infect 150 people, who would then infect another 225 people, who in turn infect 338 people.
Check out this CBC interactive to see what happens when that number rises or falls.
Alberta reported its first case of B117 community transmission in late January and doctors worry the province is starting to see the impact of rapid spread.
“This is a complete game-changer for how this third wave is going to go,” said Shazma Mithani, an Edmonton emergency physician.
Alberta’s reproduction number, or R-value, has risen steadily this month and now sits around 1.14. At the end of November, when the province was nearing the peak of its second wave, that number was at 1.12.
“This is going to really shape how the third wave is going to look like and it needs to be taken seriously,” Mithani said.
What makes it more transmissible?
Why B117 is more transmissible is “the million-dollar question,” Smith said.
Viruses are always changing and many of those mutations are inconsequential. But now and again, the genetics of a virus will evolve to make it more transmissible. In the infection race, the more transmissible strain will start to outrun its genetic counterparts.
And B117 is a fast runner.
Since it was first identified in the U.K. in December, it’s contributed to significant spread in 27 European countries and become dominant in at least 10.
“We’re on a very similar trajectory as we’ve seen in other European countries,” Smith said.
So what makes B117 more transmissible? Smith says there are two theories.
The first has to do with the spike protein, the receptor that binds the virus to the human cell. B117 mutations to the spike protein are thought to increase how tightly it holds on.
Or put another way, Smith said, the variant is stickier.
“You can imagine, if you’re exposed to the virus, with the wild type maybe you had to be exposed to 100 particles of the virus for it to stick. Now if you’re exposed to 50 particles, you’ll have one that sticks,” she said.
The second theory is that the variant replicates faster in the body, Smith says, creating a higher viral load. That means when an infected person coughs or sneezes, for example, there’s more of the virus in their respiratory droplets.
Proper physical distancing and mask-wearing are still effective ways of preventing transmission, Smith said. It just means when those measures are flouted, the risk is higher.
“It’s not like now we need four metres of distance when before we needed two,” Smith said.
Is it more deadly?
There is evidence that suggests B117 is more likely to result in severe illness compared to the wild type, but experts caution more research is needed.
In a study published in Nature earlier this month, U.K. researchers found the variant increased the risk of death by 55 per cent. While that number is concerning, the researchers note it translated to an absolute risk of death from 0.6 per cent to 0.9 per cent in men aged 55 to 69.
An analysis by Danish researchers, meanwhile, found a 64 per cent greater risk of hospitalization among variant cases.
Existing research led U.K. government scientists to conclude the variant was “likely” linked to an increased risk in hospitalization and death.
But Smith says the data from the U.K. comes from a time when that country’s health-care resources were stretched, which could have contributed to higher rates of severe outcomes.
What does this mean for Alberta?
Smith says if it weren’t for the variants, this past month may have looked different in Alberta.
“The reality is that if we didn’t have the B117, we probably would have continued to see a decrease in numbers of cases,” she said. “But unfortunately we’re in a situation where we have a more transmissible virus on our hands.”
Mithani, the emergency room physician, says the rise of that more transmissible strain should prompt the government to reintroduce stricter restrictions to contain rising cases. In the race between vaccines and variants, she worries B117 has the upper hand.
“There is a real risk of running into trouble with overwhelming the healthcare system while we’re waiting for those people to get vaccinated,” she said.
This is a complete game-changer for how this third wave is going to go.– Shazma Mithani, Edmonton ER physician
Reflecting on the experience of other countries, Hinshaw said Wednesday it may be necessary to bring in additional restrictions.
“The more that COVID-19 spreads, the more it has the opportunity to unfortunately create some very, very serious outcomes for individuals who may not have even known that they were in a location that they were being exposed,” she said.