A new wastewater test developed by Ottawa researchers is able to detect B.1.1.7, the most prominent of three new COVID-19 variants.
The Children’s Hospital of Eastern Ontario (CHEO) Research Institute, in partnership with the University of Ottawa, announced the testing advancements in the first week of February after noting they were close to success for the wastewater testing adjustments last month.
Researchers say it’s the first wastewater test of its kind in Canada for what some refer to as the “U.K. variant.” But, the test can only detect that variant, not those circulating in South Africa and Brazil.
The sewage test is particularly useful and cost-effective as it captures asymptomatic people and people who aren’t getting tested.
“The uOttawa-CHEO group indeed validated an assay last week for B.1.1.7 in wastewater (all hail @RNAguru),” announced Patrick D’Aoust, the uOttawa engineering researcher and doctoral student who is part of the CHEO-uOttawa team working on wastewater surveillance, via Twitter. “We’re hoping to apply it a couple of times a week in the near future to Ottawa, and some of the other sites we’re testing,” he added.
Tyson Graber, associate research scientist and co-lead investigator on the wastewater monitoring project, said his team discovered the U.K. variant in a sample from Barrie, Ontario, where reports of a severe outbreak that infected 200 people at a long-term care facility recently made national headlines.
Ottawa researchers obtained the Barrie samples after coming up empty on variant testing of feces in the nation’s capital region. They have been screening wastewater for COVID-19 since April 2020.
Barrie, just one hour north of Toronto, recently joined the province-wide Wastewater Surveillance Initiative for COVID monitoring in municipal wastewater, which analyzes samples from the municipality’s wastewater treatment facility.
“Wastewater surveillance serves as an additional tool that the health unit can employ in conjunction with other sources of information, such as testing data, in effectively understanding and responding to COVID within our communities,” said Dr. Lisa Simon, associate medical officer of health for the Simcoe Muskoka District Health Unit, in a statement.
The Ministry of the Environment, Conservation and Parks is supporting Ontario Tech University to run the testing and analysis on the samples. The Wastewater Treatment Facility in Barrie couriers samples directly to Ontario Tech University’s lab in Oshawa for analysis.
Graber told CBC News that wastewater surveillance is still challenged by attempting to correlate the case numbers in a given city with the wastewater signal.
In late July, CHEO noted that increases of >400% in normalized SARS-CoV-2 RNA signal in wastewater were identified 48 hours prior to reported >300% increases in positive cases that were retrospectively attributed to community-acquired infections.
In recent days, a mathematician at Queen’s University in Kingston, Ontario, said his latest modelling indicates that the B.1.1.7 variant could become the dominant strain in Ontario within just four to six weeks. There are currently about 240 cases.