COVID-19 levels in the greater Moncton area surged two weeks ago, newly released wastewater surveillance data suggests.
New Brunswick has established COVID wastewater testing pilot sites in the greater Moncton area and Natoaganeg First Nation, near Miramichi, the Department of Health announced this week.
Moncton data, dating back to June, was posted on the Public Health Agency of Canada’s COVID-19 wastewater surveillance dashboard on Tuesday.
It shows the seven-day average of viral load, expressed as the number of viral gene copies found in a millilitre of raw sewage, had been trending down since Sept. 20, when it was 21 copies/mL, and was relatively low recently.
It was six copies/mL on Sept. 29, for example, four on Oct. 3, and increased to eight on Oct. 6.
By Oct. 11, the seven-day average reached 17 copies/mL and on Oct. 13, it jumped to 43.
To see such a spike in the seven-day average within two days indicates the viral loads on Oct. 12 and Oct. 13 would have been much higher, likely around 110.
Will help people assess risk, take appropriate steps
The highest seven-day average recorded in the Moncton area was 106 copies/mL, as of Aug. 25. In the past four months, the Moncton area has had a triple-digit average only one other time — 104 copies/mL on July 14.
Some other jurisdictions, such as Vancouver Lulu Island, have seen results over 1,000 during the pandemic.
The COVID-19 wastewater surveillance project “will give people in the area [of the test sites] more information about the prevalence of COVID-19 in their community so that they can assess their risk and take the appropriate steps,” Health Minister Bruce Fitch said in a news release.
“If the wastewater signals are high or increasing, this may indicate a high level of COVID in your community,” the federal website advises.
“Consider the risks and make informed decisions about individual public health measures. Even if they’re no longer required in your community or setting, individual public health measures can help reduce the spread of COVID-19.”
More sites to be added
It’s unclear when Natoaganeg First Nation’s results will be posted on the national website, which is updated on Tuesdays and Fridays.
The province has no plans to develop its own wastewater website, said Department of Health spokesperson Adam Bowie.
The province may add more test sites, but it hasn’t said how many or when.
A wastewater working group, consisting of representatives from the departments of Health, Justice and Public Safety, Environment and Local Government, the regional health authorities and a number of other external partners, is considering “several potential sites,” Bowie said.
The Health Department said wastewater surveillance is becoming a “crucial tool for public health authorities because it is a low-cost option to obtain non-invasive biological samples from the population.”
“This can help decision-makers understand the status of community infection, sometimes before symptoms start, without requiring personal health information.”
COVID-19 is a respiratory illness with a wide range of symptoms. SARS-CoV-2, the virus that causes COVID-19, can also affect the gastrointestinal system and is shed in the feces of people infected with the virus in a form of genetic material called ribonucleic acid, or RNA, which can be found in the wastewater.
This shedding typically begins five to seven days before people develop symptoms, which is why results can be used as an early warning trigger.
Some provinces have been using wastewater monitoring to project COVID-19 trends since last year, when new data about new cases became less reliable because of restricted PCR testing.
The Department of Health first confirmed to CBC nearly six months ago that it was looking into expanding COVID-19 wastewater monitoring in New Brunswick to help track transmission and trends.
The City of Moncton has been collecting wastewater samples to monitor viral levels as part of a research project at Dalhousie University, and sharing the data with Public Health.
The Department of Health spokesperson confirmed Tuesday the province’s surveillance is a separate project, but both use Moncton’s municipal wastewater infrastructure.
“In general, wastewater sampling is often used in jurisdictions where the majority of inhabitants are serviced by a wastewater treatment facility, as opposed to privately owned septic systems,” Bowie said in an emailed statement.
Asked what, if any, additional infrastructure or costs are involved and who’s paying for them, Bowie replied, “Communities do not have to pay a fee to participate in this surveillance network, but there may be some operational costs.” He did not elaborate.
Asked why only two sites have been selected so far, Bowie said the department began with two communities “to ensure that the implementation of the project was undertaken with care and attention.”
This included establishing a relationship between Public Health authorities, wastewater utilities, and wastewater treatment facility operators, and ensuring on-site staff were trained in the methodology required for sample collection, he said.
Public Health also worked with the Public Health Agency of Canada to adopt existing COVID-19 wastewater surveillance methodology from the national microbiology laboratory in Winnipeg, and “to review lessons learned from other existing wastewater surveillance programs across the country,” Bowie said.
The samples collected are currently being tested at the Dr. Georges-L.-Dumont University Hospital Centre laboratory in Moncton. They are then sent to the national lab for further analysis, including sequencing for various strains.