How Nova Scotia's COVID-19 testing strategy has changed since the first wave

With COVID-19 once again spreading through parts of Nova Scotia, the province is taking a different approach to testing for the virus than it did during the first wave.

Capacity at the province's microbiology labs has been building since the early days of the pandemic, different types of tests have become available in recent months, and the province's current outbreak is affecting a different demographic — all contributing to the strategic shift.

When COVID-19 first arrived in Nova Scotia, testing was restricted mostly to those with multiple symptoms and close contacts of known cases. Now, public health has a much broader call for testing, including to Halifax bar staff and patrons.

At Friday's COVID-19 briefing, Nova Scotia Chief Medical Officer of Health Dr. Robert Strang said the new strategy is because of the prevalence of asymptomatic spread among the 18-35 age group in Halifax — the current epicentre of Nova Scotia's outbreak.

"With no symptoms, the only way to find people infected with COVID-19 is to test them," said Strang.

This kind of widespread testing wouldn't have been possible during the first wave because of lab capacity.

In March, the province's microbiology labs were able to complete only 200 and 250 COVID-19 tests per day.

That capacity has been gradually building, and last month Strang said the province could handle 2,500 daily tests, although it was averaging far less than that. On Thursday, lab technicians completed a record-setting 3,109 tests in 24 hours.

Even the opposition Progressive Conservatives offered some praise for the numbers, saying in a news release the uptick appeared to be "an indication that the need to extensively test is being taken seriously."

PC leader Tim Houston said he remained disappointed that testing hadn't ramped up sooner, "but I am hopeful that the government has now turned the corner."

Still, there are more people waiting for tests than the province can administer and process in a day. Strang said that as of Friday 8,000 people had identified themselves as bar staff and patrons in need of testing, creating a backlog.

Everyone who has requested it will get an appointment and results, eventually, said Strang, but they may have to wait. Some of those people — like those who have been notified of a potential exposure that requires testing — are being asked to self-isolate while they wait.

Strang asked for patience.

"We're very much building the plane and flying it at the same time when it comes to this asymptomatic testing as part of our outbreak response," he said.

Nova Scotia's testing has also broadened with the introduction of rapid tests, also called point-of-care tests. While the rapid tests are more likely to yield false results than a standard lab test, experts say the data from widespread rapid testing can provide valuable insight into the spread of the virus, and inform decisions about public health restrictions and guidelines.

Since last weekend, when the first rapid-testing site popped up for a few hours in an empty nightclub, rapid testing has attracted thousands of people to locations around Halifax. Strang said that as of Friday, 2,700 rapid tests had been administered. 

From those, at least 11 potential cases were identified, but positive results from a rapid test aren't counted in the official provincial tally of COVID-19 cases until they've been verified by a lab test. The province has not consistently reported results of followup lab tests.

What's still to come

With the recent detection of COVID-19 in wastewater in Wolfville, N.S., the province is setting up a rapid-testing site there on Monday. Strang said the research findings are not definitive, but Public Health will test that population as a precaution.

Rapid tests were deployed in long-term care homes for the first time on Friday to volunteers, employees and designated caregivers.

Strang described it as "serial testing" that will be repeated every two weeks. It launched at three Halifax-area homes and will eventually expand provincewide, he said.

"This is part of our effort to monitor, reduce and prevent the spread of COVID-19 in long-term care facilities, and none of us need a reminder about how important that is," said Strang.

Earlier this week, Premier Stephen McNeil said rotational workers might also be targeted for rapid testing in the near future. On Friday, he said travellers coming in from outside Atlantic Canada could eventually be targeted, too.

McNeil pointed to a pilot program underway in Alberta that's screening incoming international travellers to reduce quarantine time, and a recent pilot program for rapid testing by Air Canada at Toronto's Pearson airport.

"We won't be opening up to the rest of Canada any time soon," said McNeil.

But, he added, rapid testing "would have to definitely be part of that opening up."