Ontario’s new testing strategy highlights complexities of second wave: experts

Ontario’s overhaul of its COVID-19 testing strategy to focus on symptomatic and high-risk individuals highlights the fact that lessons still need to be learned as the country grapples with a second wave, public health experts said Thursday.

In a major shift, Ontario is now asking people with no symptoms to stay away from its assessment centres, with certain exceptions.

The change drew both praise and consternation, with some doctors hailing it as an example of evidence-based policy while others called it a step backwards.

Premier Doug Ford said Thursday that the province needed to be “more strategic” with testing in order to address long lines at assessment centres and a heavily burdened lab system amid a rise in cases. That came after he spent months proclaiming that everyone who wanted a test could get one.

For Dr. Susy Hota, medical director of infection prevention and control at Toronto’s University Health Network, the new direction exemplifies the sort of dilemmas authorities are facing across the country as they try to balance the demands of a global pandemic with the limited tools on-hand.

“Let’s face it, we live in a world with finite resources,” Hota said. “We’ve always had a worry about if there’s too much testing … how is that going to impact on those who really, truly need the testing because they are symptomatic or have had a high risk of exposure. We know there are limitations to what the capacity will be.”

Hota and other epidemiologists have praised the province’s efforts to ramp up the number of samples being collected for testing, a process that’s seen daily test tallies climb from under 10,000 in the spring to as high as 41,000 in recent weeks. The major hurdle, Hota said, is the province’s ability to process those results in a timely way.

Provincial health officials have said Ontario’s lab capacity has grown exponentially since the start of the pandemic, but conceded more needs to be done to process the ongoing influx of samples.

Dr. Isaac Bogoch, an infectious disease specialist at the Toronto General Hospital, described Ontario’s move as a “smart pivot” given the reality in Ontario’s labs.

He said testing results from provinces such as Alberta call the effectiveness of asymptomatic testing into question.

Dr. Deena Hinshaw, Alberta’s top doctor, said testing residents without symptoms between May and September yielded seven positive results for every 10,000 tests. She cited those results as a reason to amend the province’s testing strategy to one that closely resembles Ontario’s new approach.

“It doesn’t really make a lot of sense to offer diagnostic tests to people with no symptoms and no exposures,” Bogoch said. “Especially if we have growing lineups for diagnostic testing, and especially if we have longer turn-around times for these tests.”

But other doctors are calling for a different approach that allows the health-care system to track where the novel coronavirus is surfacing in the community rather than concentrating on individual diagnoses.

Dr. Funmi Okunola, a Vancouver-based family physician and COVID-19 advisor, said one potential solution would be to allow Canada to start offering paper-based saliva tests for home use.

She likened those to home pregnancy tests, which allow people to conduct their own screening at regular intervals before seeking more medically exact confirmation through a lab test.

While acknowledging they’re not as sensitive as the deep nasal swabs commonly used to collect lab-tested samples, she said they effectively flag positive cases during the phase when people are most contagious.

Ontario’s shift on testing highlights the need for such a tool, she said, adding the rapid-access tests should be part of any effective testing strategy.

“One of the main ways that we combat this pandemic is by testing more widely,” she said. “The technology does exist and has existed for a number of months.”

Okunola’s view has been shared by Ford, who has openly criticized Health Canada in recent days for perceived foot-dragging in approving such a test.

Health Canada is reviewing at least six antigen tests for approval, with four listed as “under review” and two waiting for more information from the companies involved.

This report by The Canadian Press was first published Sept. 24, 2020.

Michelle McQuigge, The Canadian Press