The Department of Agriculture for the U.S. state of Oregon said among animals captured during wildlife surveillance near a mink farm that recently had a coronavirus outbreak, a mink believed to have recently escaped confinement tested positive for low levels of the virus known to cause COVID-19 in humans.
State officials released a statement saying recent tests confirm mink at the farm that tested positive for the virus in late November are now clear of the virus.
KOIN reports the department conducted two rounds of follow-up tests, 14 days apart, to document the animals' recovery.
The first follow-up testing occurred Dec. 7 with only one of the 62 tested animals testing positive for barely detectable levels of the virus. With the second round of testing on Dec. 21, there were no signs of the virus among all 62 tested, indicating the mink population on the farm had recovered, ODA said.
One more round of testing will be conducted prior to releasing the quarantine, per federal guidelines.
Scientists with USDA Wildlife Services, under the direction of the Oregon Department of Fish and Wildlife are continuing to conduct wildlife surveillance near the farm, which entails trapping and testing animals.
On Tuesday, The USDA National Veterinary Services Laboratory confirmed the trapped mink, which was captured on Dec. 13, tested positive for low levels of SARS-CoV-2.
Authorities believe the captured mink had very recently escaped confinement based on the condition of the animal, necropsy findings and the location of capture. As a precaution, ODA is requesting continued surveillance, trapping and testing.
"There is no evidence that SARS-CoV-2 is circulating or has been established in the wild," said Dr. Ryan Scholz, ODA state veterinarian.
The Arizona-based conservation group, Center for Biological Diversity, said the apparent escape of the mink was potentially dangerous. "It's beyond outrageous that an infected mink can escape even from a quarantined fur farm, putting an untold range of wild animals at risk of contracting the virus," said Lori Ann Burd, environmental health director at the CBD.
U.S. authorities say the risk of the virus jumping from mink to humans is low and almost negligible when properly managed.