Cause of YK Covid-19 wastewater spike unclear, says GNWT

Last modified: April 22, 2022 at 8:16pm

The Northwest Territories government says it can’t yet explain a dramatic spike of Covid-19 levels in Yellowknife’s sewage but residents shouldn’t panic.

Recent wastewater surveillance results show the virus that causes Covid-19 has been found in the city’s sewage this month at more than three times the rate of a previous high in October 2021.

In an email to Cabin Radio on Friday, Jeremy Bird, a spokesperson for the Department of Health and Social Services, said more sampling is needed to determine what has caused that spike.


“A single sample can be an outlier, which is why we need further samples to see if there is cause for concern,” he wrote.

Bird said if an issue is found, the chief public health officer will issue a public notice or recommendations.

The GNWT uses wastewater surveillance as an early-warning system to detect community transmission, Covid-19 variants, and other respiratory viruses like the flu. It is not used for its accuracy or to determine case numbers, Bird said.

A graph created by the NWT government shows wastewater surveillance results in Yellowknife.

There has been at least one occasion when wastewater test results were not accurate in the NWT.


When there was a spike in Covid-19 cases in Yellowknife in January 2022, wastewater surveillance detected relatively low levels of the virus in the city. 

Bird said public health officials suspect this was due to the introduction of the Omicron variant, as people may have been shedding less of the virus, resulting in muted signals. 

How many people in Yellowknife – or elsewhere in the NWT – currently have Covid-19 is not clear as figures from testing are no longer as reliable as they once were. Residents, for example, are no longer required to report positive at-home tests.

One resident told Cabin Radio when they tried to report their positive test after April 1, they were told the territory was no longer collecting that information. 

According to the latest statistics from the NWT government, there are just 55 active reported cases of Covid-19 across the territory, with 25 in Yellowknife and surrounding communities.

The territory is still, however, keeping track of how many people are admitted to hospital with Covid-19 and those who die as a result of the disease.

Bird pointed out that despite the recent spike in Yellowknife’s wastewater signal, there has not been an associated rise in severe hospitalizations. 

Between April 1 and April 19, the NWT reported eight new hospitalizations and one intensive care admission. One person during that period died as a result of Covid-19.