Researchers at the University of Minnesota and Minnesota Center for Prion Research have developed a new approach to field testing chronic wasting disease (CWD).
Researchers confirmed their findings in southeast Minnesota the week in March. According to a news release announcing the test, the team is first ever to successfully deploy a CWD field test.
Right now there are limited testing options available for CWD, leading scientists to investigate several new approaches with the hopes of obstructing the disease spread.
Last spring, the MNPRO team worked with the Minnesota DNR to analyze tissue samples from CWD-positive white-tailed deer using a technique known as RT-QuIC. With that approach, team managed to obtain confirmation of protein-misfolding in just nine hours. Currently, only a handful of labs have access to the technology for CWD testing.
The MNPRO researcher team has now developed a new assay that generates a color change of red for a positive CWD result and blue for negative. They have named the test “MN-QuIC” to honor the state of Minnesota where the test was developed.
Peter Larsen, assistant professor in the Department of Veterinary and Biomedical Sciences at the University of Minnesota College of Veterinary Medicine (CVM) and co-director of MNPRO, said that MN-QuIC uses "nanoparticles to identify CWD prions in tissue samples".
"It is the product of an intense multi-disciplinary research effort that united scientists across the University of Minnesota,” Larsen said.
Larsen said the new test is also a lot cheaper than those using traditional equipment and uses field-deployable equipment to garner preliminary results in just 24 hours.
“We have performed over 100 confirmatory tests in our MNPRO lab and this was our first field-deployment," he said. "We will continue to validate MN-QuIC over the coming months and plan additional field deployments this fall.”
The team is striving for a test that could be set up at individual stations statewide, cutting down on testing bottlenecks.
“This would help prevent CWD prions from entering our food supply,” Larsen said.
According to the press release, CWD originated around 50 years ago and affects white-tailed deer, mule deer, red deer, sika deer, caribou, reindeer, elk, and moose. The transmissible neurological disease produces small lesions in an animal’s brain and ultimately results in abnormal behavior, weight loss, loss of bodily functions, and death.
While it is yet unknown whether the disease can spread to humans, the Centers for Disease Control and Prevention recommends against eating meat from CWD-infected animals. In 2020, both the Food and Drug Administration and the U.S. Department of Agriculture declared CWD-positive venison unfit for human or animal consumption, listing the meat as an adulterated product.
Earlier this month, a doe on a Beltrami County deer farm was confirmed to have had CWD.
The 77-deer herd it belonged to was in northern Minnesota, and was quarantined last year as part of an investigation that stemmed from a Houston County Farm where CWD was detected in October 2020. That farm had imported the CWD-positive deer from a Winona County herd in 2019.
According to the Minnesota Department of Agriculture, there were 395 farmed cervidae herds in Minnesota in 2018.
The field team was composed of Larsen; Peter Christenson, a graduate student in the UMN College of Science and Engineering who envisioned this new testing method; Manci Li, a PhD student in the CVM; Marc Schwabenlander, MPH, chronic wasting disease research program and outreach manager at MNPRO; and Tiffany Wolf, DVM, PhD, assistant professor in the Department of Veterinary Population Medicine at the CVM and co-director of MNPRO.
The scientists also spent the trip collecting environmental samples from areas impacted by CWD and connecting with partners in nearby Amish communities to identify culturally-appropriate CWD management strategies.