(The Canadian Press)

(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

An aerial shot of Cedar Valley Lodge this past August, LNG Canada’s newest accommodation for workers. This is where one employee is still currently isolating after a COVID-19 outbreak was first declared on Nov. 19. (Photo courtesy of LNG Canada)
54 positive COVID-19 cases associated with LNG Canada site outbreak

There’s been a two-person increase in positive cases since Tuesday (Dec. 1)

K-J Millar/The Northern View
8 confirmed COVID-19 deaths in the Northern Health Authority

Since Nov. 27, there have been 191 new cases reported in NHA

Image courtesy CDC
Confirmed COVID-19 cases in Kitamaat Village

Haisla Nation Council said there are two confirmed cases they are aware of at this time

A coal-fired power plant seen through dense smog from the window of an electric bullet train south of Beijing, December 2016. China has continued to increase thermal coal production and power generation, adding to greenhouse gas emissions that are already the world’s largest. (Tom Fletcher/Black Press)
LNG featured at B.C. energy industry, climate change conference

Hydrogen, nuclear, carbon capture needed for Canada’s net-zero goal

Victoria’s Royal Jubilee Hospital took in two COVID-19 patients from Northern Health as part of a provincial agreement. (Black Press Media file photo)
Victoria hospital takes in two COVID-19 patients from Northern Health

Royal Jubilee Hospital takes patients as part of provincial transport network

Unofficial holidays: Here’s what people are celebrating for the week of Dec. 6 to 12

Mountain Day, Dewey Decimal System Day and Lard Day are all coming up this week

Demonstrators, organized by the Public Fishery Alliance, outside the downtown Vancouver offices of Fisheries and Oceans Canada July 6 demand the marking of all hatchery chinook to allow for a sustainable public fishery while wild stocks recover. (Public Fishery Alliance Facebook photo)
Angry B.C. anglers see petition tabled in House of Commons

Salmon fishers demand better access to the healthy stocks in the public fishery

(Hotel Zed/Flytographer)
B.C. hotel grants couple 18 years of free stays after making baby on Valentines Day

Hotel Zed has announced a Kelowna couple has received free Valentines Day stays for next 18 years

Farmers raise slogans during a protest on a highway at the Delhi-Haryana state border, India, Thursday, Dec. 3, 2020. Prime Minister Justin Trudeau rejected the diplomatic scolding Canada’s envoy to India received on Friday for his recent comments in support of protesting Indian farmers. Tens of thousands of farmers have descended upon the borders of New Delhi to protest new farming laws that they say will open them to corporate exploitation. THE CANADIAN PRESS/AP-Manish Swarup
Trudeau brushes off India’s criticism for standing with farmers in anti-Modi protests

The High Commission of India in Ottawa had no comment when contacted Friday

Montreal Alouettes’ Michael Sam is set to make his pro football debut as he warms up before the first half of a CFL game against the Ottawa Redblacks in Ottawa on Friday, Aug. 7, 2015. Sam became the first publicly gay player to be drafted in the NFL. He signed with the Montreal Alouettes after being released by St. Louis, but abruptly left after playing one game. THE CANADIAN PRESS/Justin Tang
Study finds Canada a ‘laggard’ on homophobia in sports

Among females, 44 per cent of Canadians who’ve come out to teammates reported being victimized

Nurse Kath Olmstead prepares a shot as the world’s biggest study of a possible COVID-19 vaccine, developed by the National Institutes of Health and Moderna Inc., gets underway Monday, July 27, 2020, in Binghamton, N.Y. U.S. biotech firm Moderna says its vaccine is showing signs of producing lasting immunity to COVID-19, and that it will have as many as many as 125 million doses available by the end of March. THE CANADIAN PRESS/AP-Hans Pennink
Canada orders more COVID vaccines, refines advice on first doses as cases reach 400K

Canada recorded its 300,000th case of COVID-19 on Nov. 16

Apartments are seen lit up in downtown Vancouver as people are encouraged to stay home during the global COVID-19 pandemic on Thursday, Dec. 3, 2020. British Columbia’s deputy provincial health officer says provincewide data show the most important area B.C. must tackle in its response to the COVID-19 pandemic is health inequity. THE CANADIAN PRESS/Marissa Tiel
Age, income among top factors affecting well-being during pandemic, B.C. survey shows

Among respondents earning $20,000 a year or less, more than 41 per cent reported concern about food insecurity

Information about the number of COVID-19 cases in Abbotsford and other municipalities poses a danger to the public, the Provincial Health Services Authority says. (Photo: Tyler Olsen/Abbotsford News)
More city-level COVID-19 data would jeopardize public health, B.C. provincial health agency says

Agency refuses to release weekly COVID-19 case counts, citing privacy and public health concerns

Victoria-based driving instructors are concerned for their own and the community’s safety with the continued number of residents from COVID hotspots in the Lower Mainland coming to the city to take their driving road tests. (Black Press Media file photo)
Students from COVID hotspots travel to Vancouver Island for driving tests

Union leader calls on government to institute stronger travel ban

Most Read