Student Patrick D’Aoust removes a manhole cover next to a wastewater collection station on the University of Ottawa campus Thursday April 8, 2021 in Ottawa. THE CANADIAN PRESS/Adrian Wyld

Student Patrick D’Aoust removes a manhole cover next to a wastewater collection station on the University of Ottawa campus Thursday April 8, 2021 in Ottawa. THE CANADIAN PRESS/Adrian Wyld

The COVID-19 wasteland: searching for clues to the pandemic in the sewers

A rising ‘poop signal’ is most often a warning days ahead that cases are about to soar

When Ottawa Public Health officials are trying to decide whether restrictions in the city need to tighten up, they look to the normal markers like positive tests, patients in hospital, and outbreaks. But they are also among the few in the country that take cues from the city’s sewers.

Using municipal wastewater to look for evidence of the virus behind COVID-19 is part of a rapidly expanding body of science. The virus is shed in human waste, often before a patient even knows they are sick.

Wastewater testing initiatives were virtually nonexistent in Canada before COVID-19, but there are now more than two dozen universities researching the method. At least seven cities and the Northwest Territories, meanwhile, are already reporting publicly on the wastewater results.

Ottawa’s project, a combined effort from the University of Ottawa and the locally based pediatric health and research centre CHEO, was the first to report the data daily.

A rising “poop signal” — as some on Ottawa’s social media sites have taken to calling it — is most often a warning days ahead that cases are about to soar.

It happened most recently over Easter. Rob Delatolla, a civil engineering professor at the University of Ottawa and one of the brains behind the city’s COVID-19 wastewater project, said the data over the Easter long weekend was not good.

‘They’re going really high, the data points,” he said. “So it’s not the best story, but it kind of reflects, I think, what’s really happening in the city.”

Sure enough, Ottawa’s case numbers went from around 150 to 170 a day last week to more than 250 a day on several occasions in recent days.

Bernadette Conant, Chief Executive Officer of the Canadian Water Network, said the organization created a coalition to help co-ordinate and track all the work that began emerging last spring when the relationship between COVID-19 and wastewater first garnered serious attention.

“The very immediate goal is can it help public health in Canada,” she said.

“We can’t quantify it but we can say, ‘yes it has value.”

In Ottawa, the signal is quoted by real and armchair epidemiologists alike.

Delatolla said researchers are working closely with Ottawa Public Health, and every day he reports the number to Dr. Monir Taha, an associate chief public health officer in the city.

“He uses our wastewater data in his daily reports to the (epidemiology) group at Ottawa Public Health, and often times if we’re late, he’ll send us an email and say, ‘hey, guys is it coming, is everything OK,” said Delatolla.

Dr. Vera Etches, the city’s chief public health officer, quotes the signal’s data it in her tweets, letting Ottawa know it’s time to buckle back down. In early March, Etches said in media interviews that the wastewater was telling her the third wave was upon us.

But the system is not infallible. As Etches was issuing her warning, the poop signal was erroneously suggesting things were getting a lot better.

“We definitely saw the snow melt affect the signal for sure,” said Delatolla.

A combination of factors around the spring melt meant for about two weeks in mid-March the data went all wonky, diluted by extra water, affected by excess salt and sand, and delayed by the city’s new system which holds back some wastewater during the spring so as not to overwhelm the water treatment plant.

Delatolla said things are back on track now.

“What’s so amazing is we’re just a small little lab doing this,” he said. “You think about the 4,000 tests they do a day in Ottawa to get that line. We took one sample, one small, little lab, and were able to get a very similar line. So it shows you the power of using the wastewater.”

It’s also now telling the story of the variants of concern. The team developed a new test to look for the B.1.1.7 mutation first identified in the United Kingdom.

Ottawa has screened more than 1,600 cases of variants so far, but it takes days, if not weeks, to confirm which particular variant is in play.

The wastewater signal is showing that more than half the virus in the sewage is the b.1.1.7 variant.

Researchers have completed a test to look for at least one other variant so far, and they intend to share their efforts with other cities too. Vancouver, Calgary, and Ontario’s Peel region are among the seven other municipalities with wastewater COVID projects.

Conant said the idea for COVID-19 testing grew out of a project in the Netherlands, which pivoted to test for SARS-CoV-2 last winter after already testing waste for other viruses.

An online portal tracking the research run by the University of California Merced shows there are 248 universities studying the idea, along with 70 “dashboards” in 50 countries around the world publishing regular data on COVID-19 in wastewater.

The portal, called “COVIDPoops19,” even has it’s own Twitter account (and an accompanying poop emoji that has come down with a case of the novel coronavirus).

Conant said the future for the research is still being developed, but it is expected it can play a valuable role sussing out trends and outbreaks in high-risk places like long-term care homes and prisons.

Mia Rabson, The Canadian Press

Coronavirus

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

Just Posted

Peachland resident and cleanup volunteer Lloyd Stinson Sotas holds up a discarded TV riddled with bullet holes. (Aaron Hemens/Capital News)
PHOTOS: Peachland residents clean up community watershed

More than 70 people gave back to Mother Earth by assisting with the cleanup

Steven Brown is running for Penticton city council in the June by-election. (Contributed)
Penticton race director throws hat into city council ring

Steven Brown will run with a focus on small business

Penticton Vees celebrate a goal in their second win to start their season on Saturday night at the SOEC. (Brennan Phillips - Western News)
Penticton Vees head into final weekend tied for first in league

The Vees have two games to take the top spot

Coronavirus 3D illustration. (CDC photo)
Two Summerland businesses closed due to COVID-19

The businesses are listed on the Interior Health website

Memorials have been set up to honour those who died during the Second World War. (Pixabay.com)
COLUMN: It’s time to stop making comparisons to Hitler

The deadliest, most destructive war in human history should not become a metaphor

(The Canadian Press)
Trudeau won’t say whether Canada supports patent waiver for COVID-19 vaccines

‘Canada is at the table to help find a solution’

Edmonton Oilers’ Connor McDavid (97) celebrates his 100th point this season with Leon Draisaitl (29) against the Vancouver Canucks during second period NHL action in Edmonton on Saturday, May 8, 2021.THE CANADIAN PRESS/Jason Franson
Edmonton superstar McDavid hits 100-point mark as Oilers edge Canucks 4-3

NHL scoring leader needs just 53 games to reach century mark

City of Vernon Coun. Dalvir Nahal proposed two blocks of Main Street be closed to bolster recovery for downtown businesses amid the COVID-19 pandemic. (Caitlin Clow - Vernon Morning Star)
Vernon’s ‘support local’ Main Street closure would cost city $24K, staff say

Bylaw costs, loss of parking revenue and equipment logistics behind price tag

Five properties have been added to the Lake Country fire protection zone, after council moved to expand the local service area Tuesday, May 4, 2021. (Google Maps)
Lake Country expands fire protection zone, covering 5 exposed properties

The properties petitioned to join the local service area after being left out ‘for reasons unknown’

VSAR’s Air Rescue One unit assisted in a rescue in West Kelowna May 3, 2021. (VSAR screenshot)
VIDEO: VSAR’s Air Rescue One team assists in West Kelowna Rescue

The Vernon Search and Rescue helicopter team pulled off a successful rescue Monday

Officials are surveying the streets of Vernon to get a better sense of the issue of homelessness in the city, as part of the province’s point-in-time homeless count for 2021. (Brendan Shykora - Morning Star)
Province conducts homeless count in Vernon

It’s the first time Vernon has been included in the provincial homeless count

A map showing where the most number of cases were recorded from April 23 to 29. This map, revealing a breakdown of infections by neighborhood, was pulled from a data package leaked to the Vancouver Sun last week (and independently verified).
36 Abbotsford schools flagged for COVID-19 exposures in the last 2 weeks, shattering record

Clearbrook Elementary recorded an ‘exposure’ on all 11 school days

A proposed development would see two four-storey affordable housing complexes erected on Adair Street in Armstrong, next to the Nor-Val Arena. (Google Maps)
Local tenants to be prioritized for Armstrong affordable housing project

Staff have drafted an expression of interest to find a developer to move forward with on the project

Most Read