By Melissa Wagoner
Tyler Radniecki knows first-hand that there is a lot to be learned from studying the wastewater of cities. An Associate Professor of Environmental Engineering at Oregon State University, he has spent years cataloging the microbes and pathogens found in sewer systems to, amongst other things, determine the spread of diseases in a community.
Which is why, when COVID-19 arrived in 2020 he suspected his expertise could be of service. Then, when the SARS-CoV-2 was finally detected for the first time in the wastewater of Australia, he knew he had to act.
“Once the study was published, a collaboration formed between myself, Professor Christine Kelly (Professor of Bioengineering at OSU) and Dr. Ken Williamson (Director of Research and Innovation at Clean Water Services in Washington County, Oregon) to see if we could track SARS-CoV-2 in Washington County’s wastewater,” Radniecki said of the initial project, which was funded by the National Science Foundation and which eventually became a part of a program at OSU known as TRACE.
“The goal of TRACE was to use random door-to-door nasal swab testing to estimate the prevalence of COVID-19 in a community,” Radniecki said, describing the study, which aims to provide ongoing information regarding where coronavirus is spreading so that public health leaders, health care providers and individuals can make informed decisions regarding policies and procedures that might curb the spread of the virus and reduce its impacts.
“We added a wastewater component to the TRACE project to help identify neighborhood-scale hot spots and monitor the virus concentrations over a period of weeks at the wastewater treatment plants to detect shifts in COVID-19 burdens,” Radniecki said. He explained that, over time, that wastewater component has proven to be an important and more accurate addition to the study.
“This is because wastewater data does not suffer from many of the biases that are known to exist in reported clinical cases, including testing fatigue, testing avoidance and of course the asymptomatic nature of COVID-19,” Radniecki said.
This increase in accurate tracing eventually led to yet another opportunity, one with the Oregon Health Authority, which expanded the wastewater testing statewide beginning in September 2020.
“Currently we have over 40 communities across the state participating in the program,” Radniecki said, quoting a number that includes the City of Silverton, a voluntary participant whose data dates back to October 2020.
“To date the wastewater data has been most helpful in tracking the severity of COVID-19 in a community, whether it is getting better or worse over time and if variants of concern are present in the community,” Radniecki said, adding that the samples have also helped to track variants of the disease as they have made their way into the population.
“The results are emailed to each participating facility as well as posted to OHA’s Wastewater Dashboard,” Radniecki continued, listing the site, a link of which can be found on the Silver Falls School District’s home page at www.silverfallsschools.org.
And while the current numbers are trending down, as evidenced by the Wastewater Monitoring site, this sewer surveillance project is slated to continue until at least July 2023.
“As COVID-19 becomes more endemic, we expect wastewater surveillance to remain useful in detecting community outbreaks and flare-ups across the state,” Radniecki explained.
There are other uses for the technology as well.
“[W]e have already expanded to monitoring influenza state-wide,” Radniecki confirmed. “Additionally, we are gearing up to monitor cryptosporidium at select locations across the state.”
But none of these important health studies would be possible without the help of wastewater treatment employees throughout the state, a fact Radniecki is quick to acknowledge.
“We greatly appreciate their support and efforts on this project,” he said. “I would also like to say that this project is an excellent example of how a land grant institution such as OSU can respond to the needs of the state. I am honored and grateful to be able to play a role in Oregon’s response to the COVID-19 pandemic.”
Sewer Surveillance Project
• Participating wastewater treatment facilities filter 30 mL of wastewater, place the sample in a tube containing a stabilizing agent and mail it to OSU.
• Once received by the lab, the virus is extracted off the filter and quantified using a PCR test. The virus concentration is also determined and sequenced to determine what variants are present.
• Results are reported to OHA weekly, emailed to participating facilities and posted to OHA’s Wastewater Dashboard, a link to which can be found on both the OHA homepage and the homepage for the Silver Falls School District
as well.
