ODA conducted two rounds of testing, each two weeks apart, to document the animal’s recovery. Another round of testing is expected before quarantine is lifted. The first round of follow-up testing on Dec. 7 showed barely detectable levels of the virus in only one of the 62 animals tested. The second round of testing on Dec. 21 confirmed no sign of SARS-CoV-2 among the 62 tested, indicating the mink population on the farm is recovered.
The U.S. Department of Agriculture Wildlife Services is working under the Oregon Department of Fish and Wildlife to conduct trapping surveillance near the farm, which has not been publicly identified by state officials. Since Dec. 7, biologists have captured and tested nine animals, including five wild opossums, three cats, and one mink believed to have escaped the quarantine facility.
The USDA National Veterinary Services Laboratory has confirmed the trapped mink tested positive for low levels of SARS-CoV-2. The cats and opossums all tested negative. Based on the location of capture, condition of the animal, and necropsy findings, USDA Wildlife Services and ODFW believe the captured mink had recently escaped confinement. ODA has requested continued surveillance, trapping and testing as a precaution.
“There is no evidence that SARS-CoV-2 is circulating or has been established in the wild,” Dr. Ryan Scholz, ODA state veterinarian, said. “Several animals from different species were sampled, and all others were negative. Still, we are taking this situation very seriously and continuing to survey and trap near the farm. Also, we have asked USDA to run additional tests on the trapped mink, including sequencing the viral genome and a DNA test to ensure we know exactly where this mink came from.”
On Nov. 27, the NVSL confirmed mink samples submitted by ODA tested positive for SARS-CoV-2. The mink are believed to have contracted the virus from humans.
A press release from ODA said the mink farm in question is small and disclosing any individually identifiable information could reasonably result in disclosure of an individual’s medical information, specifically an individual’s COVID-19 status, and therefore the agency is declining to release this information.
According to the USDA, controlling the virus in people is ultimately the best way to mitigate the virus from spreading to animals.
By Cody Mann