B1351 coronavirus variant concerning, but Manitoba in position to stymie spread, experts say

Cases of the SARS-CoV-2 variant first detected in South Africa being reported in Manitoba are concerning, but the province is in an advantageous position to deal with it, experts say.

Manitoba public health officials announced 64 new cases of COVID-19 Tuesday, including two confirmed cases of the B1351 strain of coronavirus. Both cases were in the Winnipeg health region.

"We know that there are variants of concern throughout Canada and [that have] been detected in Manitoba. We know that these variants spread more easily, which could quickly increase our case numbers and again put demands on our health-care system," said Dr. Brent Roussin, chief provincial public health officer, during a Tuesday news conference about upcoming public health restrictions.

"With these variants of concern, we know that the virus itself is still circulating Manitoba. We need to continue with our fundamentals."

The B1351 variant has also been detected in British Columbia, Alberta, Ontario, Quebec and Nova Scotia.

There is little research about the B1351 variant.

Its spike proteins — which allow the virus to enter human cells — are sharper than the original strain of the novel coronavirus, making it more transmissible, said Carlos Farkas, a University of Manitoba post-doctoral researcher.

A mutation to an amino acid has enabled the B1351 variant to dodge people's antibodies, because the mutation changed the virus just enough that the immune system has a harder time identifying it, Farkas said.

Being able to evade antibodies has consequences for vaccine producers, and researchers are studying the effectiveness of the vaccines against various mutations.

Studies are still in their preliminary stages, but they suggest vaccines' effectiveness against the B1351 variant may be reduced.

Producers are developing booster shots for their respective vaccines to help protect against variant strains of the coronavirus.

"It's sort of like a cat-and-mouse game that the virus and the vaccine are playing with each other," said Nazeem Muhajarine, epidemiologist and University of Saskatchewan professor in community health.

"The virus is continuing to mutate and some mutations … are going to be successful in propagating, replicating, and they're going to take hold like this one did. The vaccines are going to then get a chance to target that particular variant."

Manitoba in good spot

The presence of the variant first detected in South Africa is concerning, Muhajarine said — but Manitoba is in a position where it can take significant action to prevent community spread.

There were 1,151 reported active COVID-19 cases in Manitoba on Tuesday, but hospitalizations are down to 187, including 25 patients in the intensive care unit.

The five-day test-positivity rate in Manitoba is four per cent, and it's 3.2 per cent in Winnipeg.

"[Manitoba has] a lot of capacity now that you didn't have in November, that you can go after this particular variant," Muhajarine said.

"You're in a much better place right now to deal with it."

To be successful in preventing community transmission of the B1351 variant, public health must do genomic sequencing, which analyzes a virus sample taken from a COVID-positive patient to find variants. From 10 to 15 per cent of cases should undergo genomic sequencing, Muhajarine said.

Manitoba will be further loosening its public health restrictions Friday, but Muhajarine warned that now is not the time for Manitobans to disregard public health guidance — and when they're eligible for immunization, they should get their shots.