Nova Scotia Health is now recommending that people in the province swab both their throat and nose while collecting samples for a COVID-19 rapid test.
It’s a change from what’s been the norm throughout the pandemic, which has largely been nasal swabs alone.
“Stick the swab right back past your tonsils onto the back part of your throat and just rub it back and forth about five times,” said Dr. Todd Hatchette, chief of microbiology for Nova Scotia Health. “It may make you gag, but that usually means you’re in the right spot.”
After that, the nose should be swabbed with the same stick.
In a release Friday, Nova Scotia Health said the province is the first to report research results supporting this combined method for self-administered antigen tests.
“Nova Scotia researchers have determined that collecting samples from both the throat and nose provides a more accurate rapid test result than a nose swab alone, which is the instruction provided by the manufacturer,” the release said.
“Public Health is working to update the current testing instructions that people receive when they pick up a rapid test.”
In cases where only one location of the sample is being used, it should be the nasal swab, “as the throat swab alone is not as effective as the nasal swab,” the release said.
Nova Scotia Health said this research was done in collaboration with volunteer-based community rapid testing sites, where the team was able to collect samples and perform a quality review of the procedures and outcomes.
Research ‘critical’ in COVID-19 response
The investigation compared the results of a common rapid take-home test using three sample sites: the nasal swab, the throat swab, and a combined nasal and throat swab.
When compared to PCR test results, samples from nasal or throat swabs each detected 64.5 per cent of the cases. Combining those swabs increased accuracy to between 82 and 88 per cent.
All results were confirmed with PCR testing.
Hatchette said anecdotal evidence led the researchers to do the study, and said the results are “critical” in the response to COVID-19 and emerging variants.
“I think the question came out with Omicron and again, a lot of anecdotal evidence suggested just doing your nose was missing cases,” he said. “So every time a new variant comes out, we never know if it’s changed slightly in where it likes to grow.”
The release credited the province’s “unique infrastructure of community-led rapid testing sites” for allowing the project to move forward “in a timely manner.”
“Our volunteers have been the backbone of the community COVID testing innovation through the entire pandemic,” said Barbara Goodall, research and implementation lead for community-led testing.
“We couldn’t do any of this unique work without them over the last years.”
The research project has been submitted for publication. It was authored by Goodall, as well as Drs. Jason LeBlanc, Hatchette, Lisa Barrett and Glenn Patriquin.
Comments