(The Canadian Press)

Testing wastewater could give early warning of second wave of COVID-19

Several provinces have struggled to keep up with the volume of tests needed to do that

As Canada continues to struggle to keep up with the level of COVID-19 tests needed to fend off a potential second wave of the viral disease, researchers say the best early warning system for a second wave could be right beneath our feet — in the sewers.

Several other countries have taken to testing wastewater for signs of the novel coronavirus as an indication of flare-ups in their communities.

Now researchers are beginning to look at the option in Canada.

Given that some people can pass the virus on without even knowing they have it, health officials say testing large portions of the population will be key to detecting and quashing any new community spread of COVID-19.

Several provinces have struggled to keep up with the volume of tests needed to do that, particularly in Ontario and Quebec where rates of infection remain high.

But the virus isn’t only detected in the back of people’s throats. It’s also found in waste. And while not everyone will get tested for COVID-19, most everyone uses the toilet.

“This is a tool that can actually provide an early alert to our public health in regards to re-emergence of infectivity in communities,” said Mike McKay, the executive director of the Great Lakes Institute for Environmental Research at the University of Windsor.

His research group is one of several across the country looking at whether sampling sewage could be a viable way to alert public health officials to new outbreaks.

Initially, he said researchers were excited about the possibility that measuring the amount of virus found in the pipes could provide some sense of the number of cases in a community.

But not enough is known about how much of the virus is shed in people’s waste to be able to draw many conclusions yet.

Instead, researchers hope they’ll be able to detect whether the viral load has gone up or down, allowing researchers to flag sudden spikes to public health who will be able to focus their efforts accordingly.

“If it does that, that means it’s saving lives,” said Bernadette Conant, CEO of the Canadian Water Network.

The network is in the early stages of trying to co-ordinate a pilot project in Canadian cities, including Ottawa, Windsor, Montreal and Edmonton, to develop an effective method and determine whether wastewater tests could have the public health applications they hope for.

The ultimate goal, as the technique evolves, is to use the method to root out new outbreaks in certain neighbourhoods, or even specific buildings, like long-term care homes.

That would allow public health authorities to tailor testing, lockdowns or other containment measures to that area.

“This is not a silver bullet and it’s not about replacing the basic testing and contact tracing surveillance,” Conant said. “What it does is offer the potential to fill a gap.”

The idea was tried in the Netherlands and France in the early days of the epidemic, and according to non-peer reviewed studies, both were able to detect traces of the virus in wastewater before widespread outbreaks were confirmed in those countries.

Several states in the U.S., as well as Australia and Israel, have also looked to the sewers to for signs of the virus.

It’s not a totally foreign concept in Canada either. Last year, Statistics Canada released a report on its use of wastewater samples to detect signs of increased drug use.

Accurate information about societal use of drugs, particularly from illegal sources, is difficult to get, the authors explained. So they ran a pilot project to see if sewer systems could give them a better picture.

There were limitations to what the data could tell them, but they said the advantage was the low cost, timeliness and the ability to monitor change over time at the city level — which is what researchers hope to achieve with COVID-19 tests.

Edmonton’s water utility company, Epcor, said in a statement that workers already take regular wastewater samples, so the effort and risk in gathering extra samples for testing is minimal.

As for creating a national sewage surveillance system in Canada, Conant said public health officials are beginning to show an interest but logistics, including lab capability and capacity, would still need to be worked out.

Laura Osman, The Canadian Press

Like us on Facebook and follow us on Twitter.

Want to support local journalism during the pandemic? Make a donation here.

Coronavirus

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

A grizzly that was spotted near Newens Road in Smithers has been captured, tagged and relocated. (photo from Facebook)
Smithers grizzly relocated south of Houston

Happy ending for four-year-old male who has been hanging around the Dohler Flats area of town

This weapon was seized by Houston RCMP after a traffic stop Oct. 14 (Houston RCMP photo)
Guns, cash and suspected narcotics seized

Seizure follows traffic stop on Oct. 14

This photo of approximately 10 years ago shows Laureen Fabian, on the left, and daughter Caterina Andrews. Fabian went missing last October and her daughter is looking for answers. (Contributed photo)
Laureen Fabian’s disappearance remains a mystery

It’s been a year since she went missing

Over the years, Janice Blackie-Goodine’s home in Summerland has featured elaborate Halloween displays and decorations each October. (File photo)
QUIZ: How much do you really know about Halloween?

Oct. 31 is a night of frights. How much do you know about Halloween customs and traditions?

FILE - In this Jan. 23, 1987 file photo, actor Sean Connery holds a rose in his hand as he talks about his new movie “The Name of the Rose” at a news conference in London. Scottish actor Sean Connery, considered by many to have been the best James Bond, has died aged 90, according to an announcement from his family. (AP Photo/Gerald Penny, File)
Actor Sean Connery, the ‘original’ James Bond, dies at 90

Oscar-winner was knighted by Queen Elizabeth II in 2000

This house at 414 Royal Ave. became notorious for its residents’ and visitors’ penchant for attracting police. It was also the site of a gruesome torture in August 2018. It was demolished in 2019. KTW
6-year sentence for Kamloops man who helped carve ‘rat’ into flesh of fellow gang member

Ricky Dennis was one of three men involved in the August 2018 attack

Cpl. Nathan Berze, media officer for the Mission RCMP, giving an update on the investigation at 11:30 a.m., Oct. 30. Patrick Penner photo.
VIDEO: Prisoner convicted of first-degree murder still at large from Mission Institution

When 10 p.m. count was conducted, staff discovered Roderick Muchikekwanape had disappeared

Among the pumpkin carvings created this year by Rick Chong of Abbotsford is this tribute to fallen officer Cont. Allan Young.
Abbotsford pumpkin carver’s creations include fallen police officer

Rick Chong carves and displays 30 pumpkins every year

Join Black Press Media and Do Some Good

Pay it Forward program supports local businesses in their community giving

An online fundraising campaign in support of the six-year-old boy, Edgar Colby, who was hit by a car on Range Road Oct. 25 has raised more than $62,000 in a day. (Submitted)
$62K raised in 1 day for boy in coma at BC Children’s after being hit by vehicle in Yukon

The boy’s aunt says the family is “very grateful” for the support they’ve received from the community

Health care employees take extensive precautions when working with people infected or suspected of having COVID-19. THE CANADIAN PRESS/Chris Young
WorkSafeBC disallows majority of COVID-19 job injury claims

Health care, social services employees filing the most claims

Conservative leader Erin O’Toole rises during Question Period in the House of Commons in Ottawa on Wednesday October 28, 2020. (Adrian Wyld/The Canadian Press)
Conversion therapy ban gets approval in principle, exposes Conservative divisions

Erin O’Toole himself voted in favour of the bill, as did most Conservative MPs

Most Read