Minks at two Utah fur farms have tested positive for the virus that causes covid-19 in humans, the Department of Agriculture said Monday, announcing the first U.S. cases in a species that has been widely culled in Europe after outbreaks there.

Employees at the farms in Utah, the second-largest producer of mink pelts used for coats and other luxury items, also tested positive for the coronavirus, the USDA said. Dean Taylor, Utah’s state veterinarian, told reporters Monday state and federal agencies are conducting additional testing to determine whether the minks were infected by humans or vice versa, and whether minks at other farms are sick.

Minks were discovered to be susceptible to the virus in April, when the Netherlands reported outbreaks at several farms, and mink farms in Denmark and Spain were later affected. The three countries have since killed more than a million of the animals, according to the Associated Press, but the spread has continued: As of this month, at least 27 Dutch farms have been hit. Minks are related to ferrets, which laboratory experiments have shown are highly vulnerable to the virus.

A small number of novel coronavirus cases have been confirmed in dogs, cats, and other animals in the United States and other countries, and scientists and public health agencies say evidence suggests most animals are infected by people and play no meaningful role in the spread of covid-19. Taylor emphasized that on Monday, saying “the risk of animals spreading SARS-CoV-2 to humans is considered low,” but he noted research has been “limited.”

Dutch researchers, however, said genetic analysis strongly suggested minks sickened by humans there passed the virus back to two farmworkers, in the world’s first reports of animal-to-human transmission. That conclusion has prompted calls by infectious diseases researchers for broader study of virus transmission between humans and animals.

In Utah, a state agriculture laboratory performed necropsies on several minks after “unusually large numbers of mink died at the farms,” the USDA said. A Washington State University lab found that samples of five animals were positive for the virus, and the USDA’s veterinary lab confirmed the results. Taylor said the two farms — which he declined to identify — have been quarantined and there are no immediate plans for culling.

“We don’t feel like we have enough information to make that decision at this point,” Taylor said. “Most of these farms have already got good biosecurity. I don’t think they need to worry unduly, but all of us need to take it seriously.”

The report of the outbreak is the latest bad news for the U.S. mink industry, which has faced declining production and profits in recent years and has been hard-hit by President Trump’s trade war with China, the top buyer of American mink. Production of pelts dropped 15 percent from 2018 to 2019, and the value of those sold dropped 30 percent to $59.2 million, according to a July report from the USDA.

Clayton Beckstead, a mink farmer and regional manager for the Utah Farm Bureau, said in an interview that the declines were partially due to global overproduction of mink. But the pandemic has battered the state’s mink farms, about half of which have closed this year. There are now 38 farms in the state, he said.

“Our main industry is in China. This started with the trade wars, and now nobody can travel, so we haven’t been able to sell any product,” Beckstead said. Many fur farms have received federal paycheck protection grants, but they are ineligible for relief offered to farmers and ranchers, he said.

This year “has been terrible,” he said. “It’s been one thing after another.”

The industry already stepped up biosecurity measures when the Dutch outbreaks began, he said, increasing the use of masks, gloves, rubber boots and other protective measures.

“This is our livelihood. We want to protect our animals. We want to protect our families and our employees. … We want to stop [the virus] in its tracks.”