A new modelling report from the Public Health Agency of Canada suggests if COVID-19 variants of concern were to take hold in British Columbia, existing public health measures wouldn’t be enough to keep transmission low.
In fact, the modelling for that possibility shows B.C.’s curve moving steeply upwards quicker than other provinces — including Ontario and Quebec, which have more COVID-19 cases than all other provinces.
The report says if community transmission of variants is already occurring, and B.C. were to adhere only to existing restrictions, there could be thousands of new cases a day by mid-March.
“With a combination of strong public health measures AND strict adherence to individual precautions, we can prevent a resurgence,” the report reads.
UBC professor of zoology and mathematical biologist Sarah Otto said the key to preventing that steep spike in infections is to prevent the variants of concern from transmitting freely in the community.
“We should be trying to stop the variants from establishing in the community, and that requires us to do regular testing and sequencing every case to detect whether or not these are new variants,” she said.
B.C.’s deputy provincial health officer, Dr. Reka Gustafson, told reporters Friday that the PHAC’s modelling report only presents scenarios. A resurgence in cases is certainly possible, she said, but argued the report doesn’t warrant a change in B.C.’s public health restrictions.
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B.C. is dealing with its own pandemic, and what it is doing seems to be working, she said.
“There’s actually no indication from the behaviour of the variant that we need to do anything that is different,” Gustafson said.
While the variants of concern are believed to be more infectious, they still transmit in the same way as the original strain, she added.
Otto said the PHAC’s modelling doesn’t necessarily mean B.C. will have to put harsher restrictions in place, but it does mean the province needs to share more information.
“I think we need to report in a very different way. And the province hasn’t really shifted its reporting since the new variants of concern,” she said.
“They tell us about them, but they don’t give us daily information about the number of variants.”
The province is also not releasing regular information about where the variant cases have been detected.
“They don’t tell us how many are isolating travellers, how many of them are household members of those travelers, and how many of them are up in the community. We really need that information to know where we are in British Columbia, because we predict (a spike in cases) to start about a month or two after we have community transmission,” Otto said.
“And honestly, I don’t know whether we’re already starting in that spike or whether we still have time to stave off the establishment of the new variants in British Columbia.”
As of Feb. 19, B.C. had 52 cases of B.1.1.7, the variant first found in the U.K., 20 cases of B.1.351, the variant first found in South Africa. There is also one case of B.1.525, a variant first found in Nigeria, that is not considered a variant of concern.
There were at least four cases of B.1351 under investigation in the Vancouver Coastal Health region as of Feb. 9. Provincial health officer Dr. Bonnie Henry said that these cases would be undergoing “backwards contact tracing” to determine if anyone else had been exposed.
Global News reached out to Vancouver Coastal health multiple times since Feb. 9 for an update on that process, but didn’t receive one by time of publication.
Otto said B.C. needs to expand its testing strategy to include people who aren’t showing symptoms to catch variant cases early. While it’s too early in the game for detailed information on the proportion of variant cases that don’t present symptoms, Otto said there are already reports of those cases.
Otto said about 17 per cent of COVID-19 cases are estimated to be asymptomatic. Some organizations, like the U.S. Centres for Disease Control and Infection, peg the number much higher — possibly up to 40 per cent.
British Columbia’s testing strategy does not encourage people without symptoms to get tested for COVID-19 at all, even if they have had close contact with a confirmed case. Dr. Bonnie Henry has repeatedly said that PCR tests are less accurate when symptoms aren’t present.
When asked on Friday why B.C.’s testing rate per million residents is so low compared to the rest of the country, Dr. Gustafson said no one who wants a test will be turned away.
But she confirmed the province’s strategy still encourages only people with symptoms to get tested.
“Testing without symptoms is actually not a strategy that has been proven to be particularly helpful,” she told reporters.
But Otto said in circumstances like this, it’s better to catch some cases by employing rapid asymptomatic testing than miss all of them entirely.
“We’ll catch more of them and that will help us prevent the variant from spreading,” she said.
PHAC’s report presents encouraging findings in the short term. Daily case counts are declining across the country, as are incidence rates in all age groups, the number of deaths, hospitalizations, and outbreaks in long-term care homes.
“(The) short-term forecast predicts a flattening of the trajectory, reflecting the slowdown in the rate of epidemic growth,” the report reads.
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