Variants of concern cause more than 40% of new COVID-19 cases in Ontario, experts say

Scientist warns Ontario will need to consider lockdowns again, and soon, as variants spread. "There is no way that this growth all of a sudden will stop spontaneously. This will continue, and we need to pull the emergency brake," Peter Juni told CBC News.

Sudbury moving to grey-lockdown tier on Friday, health officials say

A health-care worker prepares a dose of the Pfizer-BioNTech COVID-19 vaccine at a UHN COVID-19 vaccine clinic in Toronto. (Nathan Denette/The Canadian Press)

Variants of concern are currently responsible for about 42 per cent of new daily cases of COVID-19 in Ontario, the province's science advisory table said Thursday.

The group, made up of health experts and professionals, launched a new online dashboard focused on the variants of concern (VOCs). It shows that the variants continue to spread. The data is more or less right on track with what was predicted in models released by the table in late February.

Critically, the reproduction value — an estimate of how many people each positive case will go on to infect — for VOCs is about 1.24, the table said. Any value above one suggests that the rate of new cases is growing. 

Meanwhile, for the "old" variants — those that were present before the current VOCs were circulating — the reproduction value is 0.9.

So far in Ontario, labs have definitively linked 956 cases to the variant first found in the United Kingdom; 41 to the variant identified in South Africa and 28 to the variant found in Brazil.

But those figures are a drastic undercount of the real situation. Specific variants can only be confirmed once the samples have undergone whole genomic sequencing, an intensive process that can lead to reporting lags in the data of up to three weeks.

As of yesterday, however, 6,513 test samples had screened positive for the tell-tale mutation that indicates the presence of a VOC. Labs are still trying to pinpoint specific variants in the vast majority of those samples.

Speaking to CBC News on Thursday afternoon, Dr. Peter Juni, scientific director of the province's science table, said the province is facing a "race against time" between the variants and vaccines.

Ontario will need to tighten restrictions "very soon," he said.

"I hate to be the bearer of bad news here but looking at these numbers, unless a miracle is happening, and typically miracles don't happen that fast, this will continue," Juni said.

"There is no way that this growth all of a sudden will stop spontaneously. This will continue, and we need to pull the emergency brake."

WATCH | Doctor explains problem with virus variants:

Ontario facing new surge in coronavirus cases due to variants, expert says

2 years ago
Duration 3:15
Aggressive COVID-19 variants have the upper hand in Ontario, which is why the province needs to vaccinate as quickly as possible, said Dr. Peter Jüni of the Ontario COVID-19 Science Advisory Table.

Seeing as some variants are thought to be around 40 per cent more transmissible, how the province previously handled things will not be enough to keep things under control, Juni added.

"So what we now need to do is put all our efforts once more into controlling this thing, better than before if possible … and really vaccinate as fast as we can."

According to new provincial modelling released Thursday afternoon, the reproduction value for the B117 variant needs to be below 0.7.

Its current value is between 0.8 and 0.9, and it has only approached 0.7 once, the modelling documents say.

Provincial health officials say this "highly transmissible" variant will "soon dominate."

The science table report also says that aggressive vaccination and sticking with stay-at-home orders would "help avoid a third wave and third lockdown."

The report also notes that public health measures have helped with cases, positivity rates and hospitalizations.

Focusing vaccination on long-term care homes has helped drive down deaths, it says.

3 possibilities for daily infection rates presented

At a news conference Thursday afternoon, Adalsteinn Brown, co-chair of Ontario's COVID-19 science advisory table, said vaccinating in long-term care has been a "clear success." Now, the province is focusing its attention on the larger community. 

"If we use the tools we have to reduce risk as much as we can, as fast as we can, we will end up protecting all Ontarians," Brown said.

Provincial Medical Officer of Health Dr. David Williams said Thursday that Ontarians have another four to five months "of clear, hard work ahead of us to keep the numbers down."

Brown provided three scenarios for the next three weeks from the province's modelling, though he noted there is "a lot of uncertainty" around what will happen in the coming weeks in Ontario.

In the most optimistic scenario, there would be relatively small but continued growth, he said, topping out around 2,000 cases a day. In a medium scenario, cases "increase substantially" up to 6,000 cases a day, he said. A worst case scenario would be even more than that.

"Our behaviour over the next few weeks is critical in determining the quality of our summer," Brown added.

1,092 new cases as Sudbury set for lockdown

Ontario reported another 1,092 cases of COVID-19 on Thursday, while public health units administered a record-high number of vaccine doses.

The 40,610 shots given out yesterday are the most on a single day so far and come as a pilot project to give 194,500 doses of the AstraZeneca vaccine to some adults through pharmacies and primary care providers begins in earnest this week.

A total of 281,714 people in Ontario have now had both shots of a vaccine, according to the province's health ministry.

The new cases reported today include 293 in Toronto, 199 in Peel Region, 79 in York Region and 48 in Thunder Bay — the health unit with the highest number of active COVID-19 cases per capita.

An additional 11 cases were also confirmed in Sudbury. This morning, Ontario's Chief Medical Officer of Health Dr. David Williams said the province would implement its so-called "emergency brake" to move Sudbury to the grey-lockdown zone of the restrictions framework starting at 12:01 a.m. Friday.

 WATCH | Torontonians reflect on the first anniversary of the COVID-19 pandemic:

Torontonians reflect on the first-year anniversary of the COVID-19 pandemic

2 years ago
Duration 2:25
One year ago, the World Health Organization declared the spread of the COVID-19 virus a global pandemic. In response, Justin Trudeau designated March 11 a national day of observance. Greg Ross spoke with some Torontonians to reflect on the toll of the pandemic.

In a news release, health officials said the decision was made "due to the concerning trends in public health indicators and in consultation with the local medical officer of health.

"From March 3 to 9, 2021, the region's case rate increased by 54.1 per cent to 75.9 cases per 100,000 people," the release said. The health unit is currently in the red "control" tier of the colour-coded system.

Other public health units that saw double-digit increases were:

  • Ottawa: 64
  • Simcoe Muskoka: 43
  • Windsor-Essex: 39
  • Hamilton: 38
  • Waterloo Region: 37
  • Durham Region: 36
  • Halton Region: 33
  • Lambton: 33
  • Middlesex-London: 26
  • Niagara Region: 26
  • Eastern Ontario: 18
  • Chatham-Kent: 10

(Note: All of the figures used in this story are found on the Ministry of Health's COVID-19 dashboard or in its Daily Epidemiologic Summary. The number of cases for any region may differ from what is reported by the local public health unit on a given day, because local units report figures at different times.)

The seven-day average of new daily cases climbed to 1,252, its highest point in about a month (though it is important to note that, due to a data error, the daily case count on March 8 was artificially inflated by a few hundred infections that should have been reported the previous Saturday).

Meanwhile, labs completed 60,619 tests for SARS-CoV-2, the virus that causes COVID-19, and logged a test positivity rate of 2.4 per cent.

Labs confirmed another 35 cases of the virus variant first found in the United Kingdom, bringing the total number so far 956. They also reported 11 and two more cases caused by the variants first identified in Brazil and South Africa.

Public health units also recorded the deaths of 10 more people with the illness, pushing Ontario's official toll to 7,109.

With files from Lucas Powers and Adam Carter


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