A look inside Waterloo Region's wastewater surveillance program

You may not have heard as much about the spread of COVID-19 lately, but the threat remains.

Wastewater testing continues in Waterloo Region and over the last several weeks, it’s been picking up increased signals of the virus.

To better understand how the data is gathered and what it reveals, CTV News got an inside look at the process.

The journey starts with a visit to ground-zero for Waterloo Region’s COVID-19 wastewater surveillance, the Kitchener Wastewater Treatment Plant.

“Samples are collected five days a week during the workweek,” wastewater engineer Kristina Lee explains.

It may not looks like much, but the human wastewater contains a wealth of information, revealing what’s happening that day.

“We get snapshots of the wastewater over the 24-hour period, and it collects them in a large container,” Lee says.

A human wastewater sample is collected at the Kitchener Wastewater Treatment Plant. (Spencer Turcotte/CTV Kitchener)

SAMPLES ANALYZED IN LAB

From the treatment plant, the samples are taken to the University of Waterloo, where experts in watershed management have taken on a new role.

“We're actually a fisheries toxicology lab,” says Mark Servos, Canada Research Chair in Water Quality Protection. “We study pollution in the Grand River.”

The testing process is extensive. A sample is concentrated by settling the virus with a chemical, and then concentrated further using a centrifuge.

It may not looks like much, but human wastewater contains a wealth of information. (Spencer Turcotte/CTV Kitchener)

After that, lab staff take the samples and replicate them.

“That will double the amount of RNA turning into DNA," explains Rachel Dawe, wastewater surveillance lab manager.

Finally, the sample is amplified before the data is processed.

“That's going to allow us to quantify how much was in the actual original sample,” Servos says.

CURRENT PICTURE

The process allows the scientists to see if coronavirus is still circulating the community.

The latest public health wastewater surveillance data shows signs of the virus have increased locally over the last month.

“We're starting to see a slight increase already at the end of August,” Servos says.

Rachel Dawe, wastewater surveillance lab manager, analyzes a sample. (Spencer Turcotte/CTV Kitchener)

The wastewater signal has been dominated by the XBB variant of Omicron, but it’s not alone.

“EG.5 has been here for weeks now in the region, absolutely. It's in the wastewater. It's been here,” Servos explains.

The UW lab says they’re closely monitoring the different variants emerging, worried that more will arise as we near the colder months.

“We're concerned that we're going to see a continuing trend,” Servos says.

With policies and behaviour around COVID-19 testing changing dramatically during the pandemic, public health will continue to look at wastewater to get a clearer picture of what’s happening with COVID-19.

Waterloo Region Public Health publishes wastewater surveillance data weekly on its COVID-19 dashboard.