Montreal

How Quebec is finally using rapid testing to screen for COVID-19

New research shows frequent testing could slow the spread of the coronavirus. While the Quebec government has a stockpile of 1.3 million rapid tests it hasn't used them on a wide scale. That's about to change.

The province has 1.3 million rapid tests and hasn't yet deployed them at scale, but that's about to change

Sarah Hatchett, head of care at a nursing home in Falmouth, England, holds up a rapid antigen test for COVID-19. The Quebec government is about to roll out similar tests. (Hugh Hastings/Getty Images)

The Quebec government began taking delivery of hundreds of thousands of rapid tests for COVID-19 earlier this fall, but it hasn't deployed them in large numbers — until now.

Thousands of test kits will arrive in the Saguenay–Lac-Saint-Jean region on Friday, according to the Health Ministry. Regional public health officials will begin using them as part of their screening efforts sometime in mid-December.

The tests, which return a result in as little as 15 minutes, have variously been called a "game-changer" (Ontario Premier Doug Ford) and "less safe" as the gold-standard PCR lab test (Quebec Health Minister Christian Dubé, to Le Devoir).

The chair of McGill University's bioengineering department, Dr. David Juncker, leans to the Ford end of the spectrum —provided the tests are used effectively. Right now they are not, he said, and it's to the detriment of the broader testing effort.

"The current testing system isn't very effective in terms of contact, trace and isolate … it's too slow, it's too cumbersome, it has too many delays. That's one of the reasons we're failing in containing the spread of the pandemic," said Juncker, an expert on diagnostic testing.

The main area of concern for the provincial government — also voiced by federal officials — is the the rapid test's lower accuracy, or sensitivity, and the risk of false negatives.

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David Juncker explains how the rapid antigen test, newly approved by Health Canada, can help detect the risk of active transmission. 3:51

Those fears are overblown, in Juncker's view, because the rapid tests can still help ferret out highly infectious people.

"If we just speak about diagnostic performance … the PCR test is the most effective one," he said. "But if we think about what we want to use this for, as a public health tool that we want to use to contain and detect infectious individuals very quickly and isolate them very fast, that's where rapid tests can be very helpful."

An article published in the journal Science Advance last month by researchers at the University of Colorado-Boulder and Harvard concluded frequent, widespread testing with quick turnaround times — even of asymptomatic people — is the cheapest, most effective way of reversing soaring coronavirus caseloads.

As the lead author of the paper, Dr. Daniel Larremore, told CU Boulder Today, "it's better to have a less sensitive test with results today than a more sensitive one with results tomorrow."

Despite their limitations the currently approved rapid tests, which use the same nasal and throat swabs as the PCR test, are, in effect, a helpful yardstick for contagiousness.

"For adults with a high viral load, they have very good sensitivity … we need to think about using their strengths, which means using them frequently," Juncker said.

That hasn't been happening, at least not in Quebec.

The provincial Health Ministry rolled out rapid tests on a trial basis a few weeks ago in two locations: the Saint-Eustache hospital and Maisonneuve-Rosemont hospital in Montreal. There are conditions, however, including double-checking the results with regular PCR test.

"There is still a recommendation by the federal [government] that we need to have both tests at the same time ... and this is not very clear by the general public," Quebec's health minister said.

The tests that are being sent to the Saguenay, called ID NOW and made by Abbott Laboratories, are a streamlined version of the PCR test. Quebec has about 77,000 of them.

The province also has 1.2 million units of another Abbott test called PANBIO, which uses a different technology known as an antigen testing. It's akin to a home pregnancy test.

Provincial health officials say they'll soon begin sending those kits to Quebec City, Montreal, Lévis, the Montérégie region, the Lower North Shore, Nunavik, the Magdalen Islands and Pierre Elliott Trudeau Airport, where they will be used to screen travellers bound for the north.

That represents progress, but Juncker says the main barrier to using them effectively comes down to a pair of federal requirements: they must be administered by health professionals, and are only to be used on symptomatic patients.

"They're not being used in the kind of regime where they could have the biggest impact," he said.

with files from Cathy Senay

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