close
close

COVID-19 Wastewater Monitoring Explained | CTV News

COVID-19 Wastewater Monitoring Explained | CTV News
COVID-19 Wastewater Monitoring Explained | CTV News

You may not have heard much about the spread of COVID-19 lately, but the threat is still there.

Testing continues on wastewater in the Waterloo region, as more and more signs of the virus have been picked up in recent weeks.

To better understand how the data is collected and what it reveals, CTV News got a behind-the-scenes look at the process.

The journey begins with a visit to the epicentre of Waterloo Region’s COVID-19 wastewater surveillance: the Kitchener Wastewater Treatment Plant.

“Samples are collected five days a week, during the work week,” explains sewage expert Kristina Lee.

It may not seem like much, but human wastewater contains a wealth of information about what happened that day.

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

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

SAMPLES ANALYZED IN THE LAB

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

“We’re basically 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 precipitating the virus with a chemical, and then further concentrated using a centrifuge.

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

The laboratory staff then takes the samples and multiplies them.

“That doubles the amount of RNA that turns into DNA,” explains Rachel Dawe, manager of the sewage monitoring laboratory.

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

“This allows us to quantify how much was actually in the original sample,” says Servos.

CURRENT PHOTO

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

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

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

Rachel Dawe, manager of the wastewater monitoring laboratory, analyzes a sample. (Spencer Turcotte/CTV Kitchener)

The wastewater signal is dominated by Omicron’s XBB variant, but it is not alone.

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

The University of Washington lab says they are closely monitoring the different variants that emerge. They are concerned that more variants will emerge as the colder months approach.

“We are concerned that this trend will continue,” Servos said.

As policies and behaviors around COVID-19 testing change dramatically during the pandemic, the Public Health Service will continue to examine wastewater to get a clearer picture of what is happening with COVID-19.

Waterloo Region Public Health publishes weekly wastewater monitoring data on the COVID-19 Dashboard.