Ontario Ends COVID-19 Wastewater Surveillance: What Next?

The Ontario government ended its COVID-19 wastewater surveillance program in late July amid a surge in cases.

The program began in the fall of 2020, when the provincial government offered to support several academic laboratories’ wastewater surveillance efforts. It provided funding to the researchers and grew to include 13 labs that sampled hundreds of sites across Ontario. That funding, however, was abruptly cut off on July 31.

Although Ontario’s program is ending, the federal government will continue its wastewater surveillance across Canada, which includes one site in Toronto. In a statement provided to Medscape Medical News, the Ministry of Environment, Conservation and Parks said that the federal government is working with Ontario to expand its wastewater sampling to additional sites in the province while Ontario winds down its Wastewater Surveillance Initiative. “The Ministry of Health and the Ministry of the Environment, Conservation and Parks will work with the federal government and propose sampling sites that provide quality data for public health across the province,” the statement continued.

Researchers, including Robert Delatolla, PhD, a professor of civil engineering at the University of Ottawa, Ottawa, Ontario, Canada, who helped lead the Ontario wastewater surveillance program, are waiting for the Public Health Agency of Canada to announce which sites in the province they will monitor. Delatolla’s research group was among the first to detect COVID-19 in wastewater in April 2020.

Reducing the number of testing locations would have been understandable, he said. Keeping a portion of the program “would have allowed them to benefit from all the knowledge that they gained over the last 3.5 years — and their $80 million investment.”

Pandemic Preparedness

Wastewater testing is an effective and efficient tool for monitoring infectious diseases, such as COVID-19, respiratory syncytial virus, and influenza. While the method existed before 2020, the pandemic encouraged researchers like Delatolla to develop it further, and it quickly showed potential as an early detection system for surges in infections, according to Marc-André Langlois, PhD, a molecular virologist and professor at the University of Ottawa who serves as director of the CoVaRR-Net research network. Wastewater research is among the main initiatives of CoVaRR-Net, which studies emerging COVID variants.

The government of Canada was among the “late adopters” of wastewater monitoring, Langlois added. “Their program was slow to deploy, and the researchers really had a head start in developing new technologies.” Now, the method has been demonstrated as a reliable and cost-effective leading indicator; surges in wastewater occur about a week before hospitalizations, and the data allow hospitals to prepare by increasing staffing. New sequencing techniques can also detect pathogens that aren’t otherwise known to be spreading.

The end of Ontario’s wastewater surveillance program is “a huge blow” to the ability to track the uptick of new pathogens, said Langlois. “By cutting funding to these programs, we’re basically losing access to near real-time data.”

The decision is particularly concerning now, Langlois said, with the emergence of infectious diseases like avian flu, a virus with “pandemic potential,” and mpox, which the World Health Organization recently declared a public health emergency. Wastewater monitoring is “an extremely valuable tool in the pandemic preparedness arsenal,” he said. Langlois believes that ending Ontario’s program is counterproductive and the wrong decision.

Healthcare Planning

Compared with the methods and objectives of federal monitoring, those of the provincial program were quite different, Delatolla said. National programs serve as a tool for general pandemic preparedness. But regional monitoring provides data that are local, sampled frequently, and reported quickly, making it doubly useful for healthcare planning at hospitals and public health units.

The Ontario program also involved close collaboration with public health officials. “When you have these close relationships within the region, between the people taking the data and the institutions using the data, they seem to be more actionable,” said Delatolla. But when data are reported less frequently, “you lose the ability for those institutions to really respond.”

The collaboration between researchers and public health officials was a key component of Ontario’s program, according to Mark Servos, PhD, a research scientist and Canada research chair in water quality protection at the University of Waterloo in Waterloo, Ontario, Canada. Originally a fisheries biologist, Servos was among the first researchers to help develop COVID wastewater testing as part of the initial “grassroots” efforts.

For most of the program, Servos and his colleagues reported the data to an advisory committee two or three times per week — even daily at one point. He also met with public health units weekly to review the data, looking at trends and comparing wastewater with clinical testing data. Together, they would discuss how to interpret the data on public dashboards. “It was a very rapid turnaround in a close, collaborative relationship with the public health units,” Servos said. The federal program is “more like just generating information.”

Legacy of Knowledge

The end of Ontario’s program was disappointing to Servos. Although he understands to some extent, the decision was shortsighted, he added. Wastewater testing provides an important, large dataset that is independent of other clinical measures. “We always joke that it’s an extra leg on the stool,” Servos said.

In addition to losing those data and the relationship between research labs and public health officials, “now we’ve dismantled the lab,” Servos said. Without funding, researchers will move to other projects, so it would be difficult to bring back those qualified to conduct the surveillance. “Our ability to respond quickly to a change would be very limited.”

While a very large-scale program may not be necessary, Servos believes there should be an ongoing, core program that is designed strategically and can expand when needed. Enacting such a program would better maintain the “huge legacy of knowledge and capability that was generated,” Servos said. Research is also needed to continue learning and adapting for the next threat. It’s important not to forget the lessons learned from the COVID-19 pandemic and remain prepared for future pandemics, he added.

“The wastewater surveillance program in Ontario was a massive success,” Servos emphasized. “It was a success because of the open collaboration among the scientists, the public health units, and the municipalities.”

Gwendolyn Rak is a health reporter for Medscape Medical News based in Philadelphia.