Wastewater is a COVID-19 ‘early warning system,’ Ontario spends $12M to test sewage

It says this will enhance the ability of local public health units to identify, monitor and manage potential COVID-19 outbreaks.

“This is fantastic news,” Gail Krantzberg, a professor at the W. Booth School of Engineering Practice and Technology at McMaster University, told CBC News.

“We’re very excited that this builds our capacity at McMaster to service Ontario and help municipalities figure out what’s going on with COVID in real time.

“You see [the novel coronavirus] in wastewater several days to weeks before you actually see it measures in the community, so it’s an early warning system,” Krantzberg said.

 

Since July last year, Krantzberg and a team of researchers at McMaster University have been investigating how municipalities across the province could begin to test raw sewage for the coronavirus and quickly identify outbreaks.

She said the ability to test quickly and reliably at the municipal level could provide a real-time indicator of how many people are infected and an important tool to manage the implications of moving from one phase to another by tracking the emergence of a possible next outbreak.

“Because of the funding that we just got from the province, we’re now going to be sampling and testing Oxford County, Haldimand County, Niagara, Hamilton, many different plants, to tell them whether the signals are high or low, non-detectable, whether they’re growing or decreasing,” Krantzberg said.

“And that helps those municipalities figure out what’s going on in their communities and take appropriate action when it comes to Grey Zone or Red Zone, backtracking or opening, that kind of thing.”

Infected people excrete virus particles in feces

Similar to lab techniques used to detect pathological and chemical biomarkers such as polio, E. coli and pharmaceuticals in wastewater, researchers say it is possible to test for coronavirus and the turnaround time would be rapid. 

“We know people who are asymptomatic may not even be getting tested but they’re carrying the virus and spreading the virus. We also know that if you have the virus, whether you’re very sick or just mildly sick, you excrete virus particles in your feces and we find it in the wastewater treatment plant that same day,” Krantzberg told CBC News.

“What this tells us in real time is how much virus there is in a community because it’s showing up in wastewater before people even get tested or before they get their test results. So it’s an early warning, it’s in real time, it tells us today who is discharging into the wastewater treatment plant that’s carrying the virus in their feces, whether they know it or not.”

Provincial funding builds on work already underway

The provincial funding builds on work already underway in several municipalities. 

In addition to Hamilton, wastewater sampling for the early detection of COVID-19 is taking place in Ottawa, Windsor, Toronto, Casselman and London, as well as the Region of Peel, York Region, Durham Region, Region of Waterloo, and Essex County.

“Monitoring wastewater for COVID-19 gives us a close to real-time way to track the spread of the virus – even before people begin showing symptoms,” said Jeff Yurek, Minister of the Environment, Conservation and Park. 

“Together with clinical and public health data, wastewater monitoring can help local public health units identify potential COVID-19 outbreaks and enable more timely decisions about how and where to mobilize resources in response.”

The province is also expanding testing to include some First Nation communities, long-term care homes, retirement residences, shelters and correctional facilities.

“Since the onset of the COVID-19 pandemic a year ago, our government has been committed to using every resource at our disposal to keep Ontarians safe,” said Christine Elliott, deputy premier and Minister of Health. 

“This initiative enhances Ontario’s pandemic response by providing valuable data that will help to track and monitor COVID-19 and act as another tool to help stop the spread of this deadly virus in our communities.”