Editor’s note: This commentary is produced by Mackenzie DeRaad, a student field technician who works on Michigan State University’s wastewater surveillance project.
By Mackenzie DeRaad
Capital News Service
Universities across the globe are monitoring wastewater on their campuses for viruses like COVID-19.
It is a practice that has raised some medical privacy concerns, although researchers say there is no way to link the detection of the virus in wastewater with an individual who is sick.
In the Great Lakes Basin, universities are teaming up to join a national network, including the University of Toledo, Northwestern University, Notre Dame, Michigan State University and the University of Wisconsin.
Although the COVID-19 pandemic has shone a spotlight on the practice, wastewater surveillance dates back to John Snow, the father of epidemiology, and the 1854 cholera outbreak in London.
A research team is sampling the wastewater on the MSU campus for early detection and warning of outbreaks for students, faculty and others.
“What happens when we get infected is we might start excreting (the virus) right away. We finally get to the doctor and get the positive test, and that’s when the data gets put into the state database,” said fisheries and wildlife professor Joan Rose, who holds the Homer Nowlin Chair in Water Research.
“When you’re in the sewer, you’re getting closer to the source,” Rose added.
Well, the team is not actually in the sewer.
The researchers deploy automatic wastewater samplers on a hook with a hose going down into the wastewater.
Multiple samples are taken throughout the day. The team sends them to a lab for analysis.
The wastewater data provides a warning as much as 24 days faster than clinical tests, said Erin Dreelin, an associate professor in the university’s Department of Fisheries and Wildlife and coordinator of MSU Water Science Network.
An early warning may be helpful from a public health perspective, but “getting closer to the source” raises privacy concerns among some people. Experts say there is no need for worry.
“Wastewater surveillance is a noninvasive and privacy-protecting method of monitoring for disease in a population,” said Chelsea Wuth, a public information officer in the Michigan Department of Health and Human Services.
“This testing uses a pooled community sample that reflects a population of individuals, not the individuals themselves,” she said.
A study in the Journal of Law and the Biosciences supports that assertion, arguing that population-level surveillance close to the source does not violate individual privacy rights.
Even so, to address concerns that samples taken from small populations might identify people, “results from small facilities have been restricted from public view and can only be viewed by appropriate public health staff,” Wuth said.
But what about genetic markers that can identify individuals?
“Testing conducted by this project is only testing for the presence of the SARS-CoV-2 virus, not human genes. Therefore, it cannot identify individuals and, instead, provides data on a group of individuals,” Wuth said.
The public can view group data on Michigan COVID-19 Wastewater Testing Dashboard, Sentinel Wastewater Epidemiology Evaluation Project (SWEEP) Dashboard and the Centers for Disease Control and Prevention COVID Data Tracker for Wastewater Surveillance.
While public, this data doesn’t show individual cases.
And it’s secure, Wuth said.
“Michigan has extensive protections to prevent security breaches of data,” she said. “If a security breach were to occur, the state Department of Technology, Management and Budget would take action to re-secure the data and minimize any potential harm that could occur.”
“The state agencies have decades of experience in protecting the privacy of Michigan residents,” she said.
Among those raising privacy concerns is Steve Hrudey, professor emeritus in the University of Alberta Laboratory Medicine and Pathology Department.
He argues that informed consent is not entirely possible in wastewater surveillance.
“You can zero in on one area, which may be used to discriminate against the people living there,” Hrudey said.
Authorities could show up on one’s doorstep and require testing, which has happened in Singapore and Hong Kong, he said.
While surveilling wastewater close to residences connects positive test results with specific groups, Kim Gilbride, professor and molecular microbiologist at Toronto Metropolitan University, said there is no way of knowing which positive test came from which individual.
Wastewater is not synonymous with fingerprints — it can’t name you, experts say.
Privacy concerns can be laid to rest for now because wastewater surveillance experts agree that community data is secure.
An interactive global map of wastewater monitoring sites, dashboards, universities and countries can be found on COVIDPoops19.