(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

A laboratory technician holds a dose of a COVID-19 novel coronavirus vaccine candidate that’s ready for trial on monkeys at the National Primate Research Center of Thailand. (Mladen Antonov - AFP)
Interior Health reports 66 new COVID-19 infections

570 cases are active; 18 in hospital

(File photo)
Okanagan-Shuswap real estate markets not slowing down

Residential sales in the Central, North Okanagan and Shuswap beat last year’s sales by 71 per cent

A crowd of approximately 6,500 packed into Stuart Park in downtown Kelowna to ring in 2018. (Contributed)
Downtown Kelowna New Year’s celebration cancelled

The popular New York New Year’s event has been cancelled due to the COVID-19 pandemic

(Google Maps)
UPDATE: COVID-19 case confirmed at Mar Jok, Rutland Senior Secondary

School District 23 said the individual is now self-isolating

Residents should run their taps until cold before using their water. (Black Press file photo)
Westside water quality advisory back on tap

Leak repair at Westshore Estates affecting some properties, again

An Enderby restaurant and pub was shut down Sunday afternoon, Nov. 29, 2020 as a precaution after a guest reportedly tested positive for COVID-19. (Howard Johnson photo)
North Okanagan pub reopens after COVID-19 scare

After a guest reportedly tested positive for the virus, staff test results came back negative

Alix Longland
Trauma resources ready for North Okanagan refugees

Family Resource Centre working with UBCO social work grad to reach out to local refugees

Elkhart Gas Station, located on Highway 97C about 60 kilometres west of Peachland, opened in November 2020. (Google maps)
The Okanagan Connector now has a gas station

The highway previously ran for over 117 kilometres without a place to fuel up

The Hughes’ Grinch was stolen from their front yard Wednesday, Dec. 1, 2020. The Santa suit the Grinch is wearing is 50 years old and has sentimental value. It was once worn by April Hughes’ dad. (Hughes photo)
Grinch stolen from Penticton home is ‘irreplaceable’

The Hughes have had a Christmas display for 25 years on Grandy Avenue in Penticton

Midway RCMP’s Cpl. Phil Peters spoke at Greenwood’s city council meeting Monday, Nov. 23. Photo: Laurie Tritschler
B.C. Mountie builds fire to warm suspect with hypothermia prior to rescue

Cpl. Phil Peters said the civilian helped police track, apprehend and eventually rescue the suspect

Premier John Horgan leaves the podium following his first press conference of the year as he comments on various questions from the media in the Press Gallery at B.C. Legislature in Victoria, B.C., on Monday, January 13, 2020. THE CANADIAN PRESS/Chad Hipolito
Revelstoke COVID-19 cluster linked to non-essential travel: Horgan

There have been 46 cases of COVID-19 in the community

Cannabis bought in British Columbia (Ashley Wadhwani/Black Press Media)
Is it time to start thinking about greener ways to package cannabis?

Packaging suppliers are still figuring eco-friendly and affordable packaging options that fit the mandates of Cannabis Regulations

Students at Lavington Elementary crammed a car full of non-perishables for those in the community facing food insecurity. Spearheaded by teacher January Peebles (left), the donations were picked up by Give LUCK founder Myrika Godard, who works to connect donors with donees in the North Okanagan. (Give LUCK photo)

Most Read