Giving a school-aged child an invasive, uncomfortable nasal swab test for COVID-19 might be tricky.
Asking them to spit in a cup? It could be a simpler approach.
That’s the thought process behind calls from both researchers and public health officials to launch saliva tests in schools. But despite international efforts to make this option a reality, there’s still no word on when saliva-based testing for COVID-19 will be allowed in Canada.
“School is just around the corner, and I feel like we’re lagging behind,” said researcher Dr. Michael Glogauer, a professor in the faculty of dentistry at the University of Toronto who has been focusing on saliva as a diagnostic tool for the last two decades. “We’re further behind than we should be on this.”
So why isn’t it available yet?
South of the border, five saliva-based tests have been approved so far by the U.S. Food and Drug Administration (FDA)- including, most recently, a headline-making test for COVID-19 developed by Yale University researchers with funding support from the National Basketball Association.
Major League Baseball is already using saliva tests for players, and some American universities have also started offering saliva-based options to test students back on campus this fall.
Much like the current tests which send nasal swab samples back to a lab, those tests — and other similar ones being developed in Canada — involve sending saliva samples to a lab for processing, with results back in around 24 hours.
But no such saliva-based tests have yet been authorized by Health Canada.
“Health Canada reviews all COVID-19-related applications as quickly as possible without compromising patient safety,” said spokesperson Eric Morrissette in a statement provided to CBC News.
Only one company, U.S-based DiaCarta, has submitted a COVID-19 saliva-based test to Health Canada for review so far.
Canada ‘always playing catch-up’
Glogauer, who is also head of dental oncology at Princess Margaret Cancer Centre, said Canada is “always playing catch-up.”
Dozens of research teams at the University of Toronto and across the country are exploring saliva-based testing, he said, and dealing with ongoing “back and forth” with government officials.
Glogauer’s own team is focusing on one of the FDA-approved saliva-based lab tests already in use in the U.S. and is now applying for Health Canada approval.
“It’s effective, it works, it can be used within the laboratory system. It’s plug and play,” he said.
“It’s just a matter of Health Canada approving these tests, and getting to work on it.”
In Toronto, the city with Canada’s largest public school board, public health officials urgently want a saliva testing pilot project, and are calling on both the federal and provincial governments to give the green light so local schools can explore how to collect saliva.
“It’s less obtrusive, a little easier,” said Joe Cressy, chair of Toronto’s board of health, who works closely with the Toronto Public Health officials recommending this approach.
“Given that we need to be so proactive in testing in congregate school settings, it could be a really important and helpful way to help us prevent the spread of COVID-19.”
Parents often decline the current swab testing because they don’t want their children to go through that experience, noted the city’s associate medical officer of health Dr. Vinita Dubey.
She said research shows saliva-based testing may be slightly less accurate, “but it may have some benefits in its ease of use.”
Provincial officials say they’re also asking for Health Canada to approve a saliva test.
“If and when a saliva-based collection kit has been approved for use in Canada, recommendations for use in Ontario will be provided by the province,” a spokesperson for the Ontario’s health ministry told CBC News in a statement.
Concerns over result delays
While calls for new testing options may be growing, Dr. Zain Chagla, a Hamilton, Ont.-based infectious disease specialist, said any eventual rollout of saliva testing in schools or elsewhere needs to be done “thoughtfully.”
Since current models being explored would require existing lab facilities, he said widespread testing could eat up crucial resources, particularly as the regular cold and flu season approaches.
“You may run into issues with slowdowns and delayed turnaround times,” Chagla said.
That’s the impetus for some teams who are also exploring how to create near-instant saliva-based test kits, which could work like a pregnancy test — offering a quick result, without requiring lab facilities at all.
University of Saskatchewan researchers, for instance, are currently developing a saliva-based COVID-19 home testing kit which would provide results in a few minutes, but the technology isn’t expected to be available until the spring of 2021.
Glogauer said his team is exploring similar options, and stressed even lab-based testing of saliva samples could be helpful for schools.
While the samples would still need to be processed off-site, he said the collection could be done easily at home by parents or in schools by existing staff, without requiring medical teams in full protective gear.
“This would be an ideal test to be used on high school students, for example, as a means toward screening, detecting asymptomatic spreaders — giving confidence to the system that students testing positive can be isolated,” he said.
Glogauer said multiple private schools in the Toronto area have already expressed interest.
All that’s needed now, he said, is a “rubber stamp.”