Vancouver Island's race between variants and vaccines

Just when the world was ready to celebrate the start of immunizations and a light at the end of the COVID-19 tunnel, a new problem emerged, threatening to throw a wrench in people’s hopes of achieving a post-pandemic world by fall.

This problem arrived in British Columbia in February, then quickly found a stronghold and has been spreading at a worrying pace ever since.

About one month ago, BC had 46 recorded cases of COVID-19 in which the virus had mutated into a version—a “variant”—that spreads more easily. The latest counts show that within just four weeks, that number has grown to 638, with 89 of those cases currently active.

In any virus, variants emerge constantly, and COVID-19 has been no exception. But some variants are more dangerous than others, hence the common term “variants of concern.”

So far, three variants of concern have been detected in BC: the B117 variant, which originated in the UK, the B1351 variant from South Africa, and most recently the P1 variant first seen in Brazil. The most widespread of these is the UK variant, with a total of 588 cases recorded in BC.

Part of the growth in cases in the province can be attributed to a new system implemented in the first week of March that screens all positive COVID-19 cases for possible variants of concern, yielding faster data.

Seven of BC’s variant cases are on Vancouver Island, and according to Island Health medical health officer Dr. Mike Benusic, there is no concern that the variant has spread any more than that. But that does not mean we’re completely in the clear.

“There's some new evidence to suggest that [the UK variant causes] more severe disease than non-variants. What's actually really good to know about the B117 is that it doesn't appear that vaccines are substantially less effective against [it],” he said.

As of March 12, the Vancouver Island Health Authority is slightly ahead of the curve when it comes to vaccinating its population compared to the rest of the province. While 6% of the population of BC have received at least one dose of the vaccine, 8% of Island Health residents have had the same.

According to Benusic, immunization is the strongest line of defence against transmission of variants. The chances of a variant ripping through a community decrease if a larger proportion of that population is vaccinated.

“The biggest thing we can do as a population right now to prevent the spread of variants of concern is to increase our level of immunity as a population as soon as possible, because that'll decrease the risk that if a variant is introduced, that it's going to end up spreading in the community,” Benusic said.

He added that the Vancouver Island Health Authority is well on its way to achieving the goal of offering a first dose of vaccine to every adult in the region by the end of July.

But with several months remaining before herd immunity can be achieved, the province is working on first finding everyone who has contracted a variant of the virus to make sure they and people in their households self-isolate. The process of identifying those variant cases took much longer until recently.

“In the early days when variants of concern were identified in BC, the only way that we would identify that is if we made a specific request to the province to do whole-genome sequencing on a case,” Benusic said.

Up until late February, this process could take as long as two weeks. But in early March, the province implemented a system that screens every positive COVID-19 case for the likelihood of being a variant strain. The time it takes to conduct whole-genome sequencing has also been decreased to three to five days, according to provincial health officer Dr. Bonnie Henry.

The vast majority of variant cases are located in the Lower Mainland, mostly concentrated in the Fraser Health region. Benusic says there are several reasons why.

“We know that population density, as well as outbreaks that can happen within industries and a lot of travel between areas, are some of the determining factors for COVID-19 transmission within a population,” he said.

“We do have the benefit of, well, being an island. It does create more of a barrier to people travelling… as opposed to how freely people can travel in the Lower Mainland.”

Island Health also has the advantage of not being home to the types of large industries and workplace settings—such as industrial slaughterhouses—that are more conducive to rapid COVID-19 spread, like there are in regions like the Fraser Health Authority.

“It would make sense, then, that if there are variants of concern spreading within a community, that it would follow how the pandemic has played out so far with non-variants, and that we would likely expect to see spread in the Lower Mainland before we see spread on Vancouver Island,” Benusic said.

While the health authority does not believe there is any community spread from the known variants of concern that have been detected in the Island Health region thus far, Benusic says it’s reasonable to expect that variants could be spreading without the health authorities’ knowledge.

In the meantime, public health officials have begun easing some restrictions in light of the vaccines’ early success in curbing transmission rates among long term care home residents and healthcare workers.

The advent of warmer weather and the end of respiratory illness season also contributed to Dr. Bonnie Henry announcing a change in the public health order on social gatherings: people in BC can now hang out in groups of up to 10 people as long as these gatherings happen outdoors.

“It is important after these months that we have put to trying to prevent the spread, that we need to...focus on some of the things that we can do safely. Outdoors is where we need to focus right now,” she said on Thursday.

“Being able to have those important connections that we need, but do them in a way that’s not going to put people at risk.”

“This is a bug that really enjoys changing itself”

Since the start of the pandemic, the Sars-CoV-2 virus has undergone a plethora of mutations, but only a few have been termed “variants of concern.”

There are typically three factors that can earn a variant that classification: if it is thought to or known to be more easily transmitted from person to person, if it causes a more severe illness or increases likelihood of death, or if vaccines may not be as effective against the variant.

Dr. Howard Brunt, a recently retired epidemiologist in Victoria (and the father of Capital Daily’s community manager), has been following the COVID-19 virus and its mutations closely since they first emerged.

“There's no question that this is a bug that really enjoys changing itself, as all viruses do, but it seems very good at shape-shifting,” said Brunt.

In particular, he says the Brazil or P1 variant is concerning because of trends seen in its country of origin.

“It is much more worrisome as a variant because it has an incredibly high transmission rate… and even more concerning, it was reinfecting people who'd already had COVID and who had an earlier version of COVID [in Brazil],” he said.

Benusic shares this worry, adding that the P1 variant is the one vaccines would be least effective against.

“The really good news from my point of view is virtually all of these [vaccine manufacturing] companies are now retooling or in the process of retooling their vaccines to be more effective against these variants,” Brunt added.

Pfizer-BioNTech and Moderna vaccines were found to be less effective against certain variants but are among several companies working on creating a booster shot designed to target variants which the original dose may have missed.

Thus far, BC has only seen 14 cases of the Brazil P1 variant, all of which were reported this week.

“They were all associated with one group cluster in the Vancouver Coastal Health region. We have not seen additional transmission from that group,” Dr. Bonnie Henry said on Thursday.

A presentation slide that showed where variants of concern originate from suggests that none of these cases are linked to travel, and are instead “locally acquired.”

Source: BC Ministry of Health

There is no information yet on how these new variants arrived in BC.

In fact, when it comes to variants of concern, the source of transmission is unknown in about 25% of cases in BC—a figure that has remained steady since they were first detected in February.

A Simon Fraser University study published in mid-February suggests that, statistically, by the time the first variant of concern is detected, “there will be a couple of dozen active cases in the community and potentially over 80.”

This scenario factors in the use of only whole-genome sequencing to catch variants of concern in the first place, which means there is a lag of one to two weeks before a case is detected. This is the strategy BC was using until early March, by which point there were already over 200 detected variants of concern.

Now that the province screens every positive COVID-19 case for possible variants of concern, the likelihood of catching these cases while they are still within their infectious period is much higher.

At the moment, the provincial government knows about 89 active cases of variants of concern in BC.

Island Health did not specify how many active cases there are in the region, citing privacy concerns.

Vaccinations picking up

Across BC, immunization efforts will get a boost starting next week when health officials begin administering the first doses of the AstraZeneca vaccine, but Vancouver Islanders will likely not receive many of those shots until April.

The AstraZeneca vaccine is being used to launch a parallel immunization program—alongside the age-based approach with the Pfizer and Moderna vaccines—targeting key priority populations. On Thursday, Henry offered more details about who will be getting those first doses this month.

“Right now, with the limited amount that we got in this week, we have made the decision here in BC to target the areas where we are confident it can make the most difference in protecting our communities and that is around workplaces where we’re seeing clusters and outbreaks,” she said.

Specifically, the plan is to offer first doses to workers in the food processing industry, large industrial campsites, and in some farm operations and nurseries—all settings where clusters and outbreaks have been rampant, largely as a result of people not being able to distance due to close quarters in their workplaces or in group accommodation settings.

These environments are mostly set in the Fraser Health region—where cases of the B117 are at their highest—and in the Interior and Northern health regions.

“That’s our strategy for the first part, and then, as we are expecting more of the vaccine in April, we will be looking at how [to] roll it out from there,” Henry said.

The AstraZeneca vaccine, along with the newly approved Johnson & Johnson vaccine, are both fridge-stable meaning they don’t need special equipment in order to be transported and stored.

This means the province is looking at partnering with pharmacies to help administer them.

So far, one-in-thirteen residents in the Vancouver Island Health Authority has already received one dose of the COVID-19 vaccine, while only seven cases of variants of concern have been detected, even after screening measures were bolstered.

With supply chains holding steady and two new sources of immunization on the horizon, it appears that, at least for now, vaccines are winning the race against variants on Vancouver Island.

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