CORVALLIS, Ore. - Oregon State University will conduct its sixth round of TRACE-COVID-19 door-to-door sampling throughout Corvallis the weekend of March 13 and 14 for the coronavirus that causes COVID-19.
"It is encouraging that the overall prevalence of the virus in Corvallis has remained low throughout the pandemic," said TRACE project leader Ben Dalziel, an assistant professor in the OSU College of Science. "Even with more and more people being vaccinated, it is no time to stop being careful or to stop monitoring community prevalence of the virus. More testing will assist public health efforts."
All nasal swab samples containing the virus, as well as city wastewater samples collected under the direction of Tyler Radniecki and Christine Kelly of the OSU College of Engineering, will be genetically sequenced to determine if any variants of elevated concern are present in Corvallis, Dalziel added.
Thirty teams of TRACE Community field workers will fan out to 30 city of Corvallis neighborhoods and invite members of each household they visit to participate in the study. Those who choose to take part will be asked to provide information such as their name and date of birth; fill out a simple consent form; and answer a few confidential, health-related questions.
Participants will be given a nasal-swab test kit that they administer to themselves and to their minor children if they want them to take part. The field staff will wait outside, and the participants will leave the completed test kits outside their front door.
The field workers will leave participants with information about the project and how they will receive their results - available within a few days - as well as health guidance from the Benton County Health Department and the Centers for Disease Control and Prevention. Participants in the effort will receive their results and those of their minor children by secure email with receipt by mail as a backup. Personal information will be safeguarded.
The TRACE project is a collaboration of five OSU colleges - Science, Agricultural Sciences, the Carlson College of Veterinary Medicine, Engineering, and Public Health and Human Sciences - plus the OSU Center for Genome Research and Biocomputing.
The project works in partnership with the Benton County Health Department in Corvallis and other county health departments around the state. TRACE Community has also conducted sampling in Bend, Newport, Hermiston, Eugene and Redmond.
The diagnostic testing component of TRACE operates through a partnership between the Oregon Veterinary Diagnostic Laboratory, which is located at OSU, and Willamette Valley Toxicology.
OSU researchers have conducted weekly testing of Corvallis community wastewater since May 2020. Genetic evidence of the virus, shed by people who are infected, has been generally trending downward in recent weeks, according to Oregon State researchers.
In September 2020, during the fifth round of TRACE Community door-to-door sampling in Corvallis, wastewater analysis was consistent with the community prevalence estimate of three cases per 1,000 residents that the nasal swab testing suggested.
"TRACE's collaboration with wastewater researchers Tiffany Garcia and Taal Levi in the OSU College of Agricultural Sciences has been a huge benefit," Radniecki said. "They have provided additional wastewater samples and data from their ongoing Corvallis monitoring project to help TRACE determine which neighborhoods would be most valuable to sample door to door."
The TRACE prevalence estimates are based on a variety of inputs including test sensitivity, number of people tested and where those testing positive live. In Corvallis, where the participation percentage has consistently been around 70%, a weekend of door-to-door visits can produce nearly 700 samples.
"TRACE hopes that people will consider participating if our team knocks on their door," said project co-leader Jeff Bethel, an associate professor in OSU's College of Public Health and Human Sciences. "Participation is extremely important so we can calculate a valid estimate of prevalence in the community. We really hope people won't say no because they were recently vaccinated or tested."
TRACE-COVID-19 has received funding from OSU, the David and Lucile Packard Foundation, PacificSource Health Plans and the Oregon Health Authority and has been aided by work from the OSU Foundation and the OSU Alumni Association.
