Tough restrictions needed to halt spread of coronavirus variant, experts say
The B117 coronavirus variant could become dominant in Ontario within weeks
Even as COVID-19 case numbers in Ottawa trend downward, two experts say the province will likely need to maintain strict restrictions to keep a more contagious variant of the coronavirus at bay.
Troy Day, a member of Ontario's modelling table and a mathematician at Queen's University in Kingston, Ont., said his latest modelling suggests the B117 variant, first identified in the United Kingdom, will become the dominant strain in Ontario within four to six weeks.
At that point, case counts could rise again — even with existing restrictions — as scientists say that variant is at least 30 per cent more transmissible.
Day said that means it may be too early to consider loosening restrictions, given limited surveillance and data about the prevalence of the new variant.
"I would doubt we're going to have enough information by [this week] to make a decision that's really any more informed than we currently are," said Day. "I would err on the side of caution."
To lift or not to lift restrictions?
Ontario's stay-at-home order is set to run out Wednesday, and Premier Doug Ford could announce the reopening timetable as soon as today.
According to government sources who spoke to the Canadian Press, a gradual reopening will likely begin in regions where COVID-19 infection rates are lowest.
The province shut down non-essential businesses in December and followed that weeks later, amid a post-holiday COVID-19 surge, with an emergency declaration and a stay-at-home order.
Cases have since declined, with Ottawa's seven-day rolling average of new daily cases down to just under 33 on Sunday, from a high of 161. 3 on Jan. 14.
But Doug Manuel, a senior scientist at The Ottawa Hospital and a member of the province's COVID-19 advisory table, said the B117 variant is spreading in Ontario faster than COVID-19 vaccines are being administered.
Like Day, Manuel said it may be necessary to tighten or maintain restrictions to keep cases low.
"We're not out of the storm — we're in the eye of the storm," said Manuel. "[We have to] batten down the hatches, clear off the decks, get the kids below deck and brace ourselves for that next wave coming."
WATCH | Variants could change Canada's COVID-19 situation 'rapidly':
Public health officials have partially blamed the B117 variant for a rapid outbreak at a long-term care home in Barrie, Ont., that infected over 200 residents, staff members and essential caregivers. At least 69 residents and one essential caregiver died.
Ottawa recorded its first COVID-19 case caused by the variant on Dec. 27, with four cases confirmed so far, according to data from Public Health Ontario.
Manuel said advisory table members met last week with scientific and medical colleagues from the U.K. who shared cautionary words.
"They required a lot of restrictions to start moving their cases down with the new variant and [they have] a higher level of natural immunity and a higher level vaccination rate," Manuel said.
Testing for variants
Day's latest model includes new data from a Jan. 20 scan of positive COVID-19 tests that found more than 103 cases involving "variants of concern" out of 1,880 swabs.
When samples from the Barrie care home were excluded, 1.2 per cent were found to be carrying the mutation.
Day said he thinks the B117 variant now accounts for around four per cent of new cases.
"If what happened in the U.K. in November and December is happening here, then our current decrease in case numbers ... is masking something under the surface," he said.
Day said testing will need to expand to also look for "variants of concern," including those first identified South Africa and Brazil.
Ontario's Chief Medical Officer Dr. David Williams has said the province has come up with a test that can do just that, while a team of researchers at CHEO recently developed a test that can detect the B117 variant in wastewater.
Experts will only be able to determine how quickly the variant is spreading, Day said, after more data is collected from tests like these.
"It might mean that we're going to have to adopt different or stricter measures, depending on how effective the things we're currently doing are," he said.