Variants of concern behind recent rise in Alberta COVID-19 cases

Over the weekend, the P.1 variant was detected in Toronto, Ont., making the city perhaps the first in the world to identify cases of all three current variants of concern.

Edmonton — Variant cases in Alberta appear to be part of what's driving a recent surge in new cases in the province, according to the latest data.

As of Tuesday morning, 3,068 variant of concern cases had been identified, including 2,152 considered to be active.

Variants now account for 27.2 per cent of active cases, up from 10.7 per cent two weeks earlier.

The rapid rise mirrors a similar increase in daily new cases, with Alberta reporting at least 400 new cases every day since March 17.

"With the continued increase of variants of concern, maintaining public health measures and individual precautions is crucial to reducing infection rates and avoiding a rapid re-acceleration of the epidemic and its severe outcomes, including hospitalization and deaths," Canada's Chief Public Health Officer Dr. Theresa Tam said in a statement.

Dr. Tam noted the growing number of vaccinations give "cause for optimism (that) widespread and lasting immunity can be achieved."

VARIANT CONCERN

A variant is identified when enough mutations have occurred to change a minor portion of a virus’s genetic code.

Variants are more transmissible and can impact developed antibodies, making them particularly concerning for public health officials.

The fear is that the faster-spreading variants will overwhelm the health care system before the number of vaccinations can catch-up and those shots have been given the time to take effect.

"This is spreading much faster than the first or second wave," said Dr. Gosia Gasperowicz, a developmental biologist at the University of Calgary.

Variants are driving a pair of worrying trends.

Alberta's active cases have risen to near 8,000, about where they were in late January.

And, test positivity remains stubbornly high, having exceeded five per cent for the last eight straight days.

"We're giving it an opportunity to grow and it grows faster than the original variant," said Dr. Gasperowicz.

The numbers of hospitalizations and deaths have levelled off or slightly declined in recent days but could rise if active cases continue to mount.

"We need a stronger lockdown," said Dr. Gasperowicz.

Meanwhile, vaccine distribution continues to grow, with more than 600,000 doses administered so far. But she says the variants' growth will outpace vaccine distribution in the short term.

"By itself, it won't bend the curve," she said of vaccinations.

SEPARATE SCREENING

In Alberta, identifying a variant case requires a separate screening, meaning individuals are notified twice: once for a positive COVID-19 test, and again if a variant is identified.

All confirmed COVID-19 cases have been screened for variants since Feb. 1, 2021. Alberta Health notes the need for a second screening delays the reporting of variant cases by up to two days, though delays in other provinces are often much longer.

"The vast majority of variants of concern are reported immediately, with only a small number needing follow up testing for confirmation," an Alberta Health spokesperson wrote in an email.