Minks that were culled in Denmark over coronavirus concerns are beginning to rise out of their shallow graves, according to local news reports.
Earlier this month, Prime Minister Mette Frederiksen said at least 12 people were infected with a mutated form of the coronavirus, originating at mink farms, prompting Denmark to order that more than 15 million minks be culled over fears that the strain would spread to humans.
Related: Can pets transmit COVID-19 from their fur?
In a new development, some of the dead mink bodies have begun to come up out of the spots they were buried, creating a new public health concern.
“As the bodies decay, gases can be formed,” a national police spokesman told a local news outlet, according to The Guardian. “This causes the whole thing to expand a little. In this way, in the worst cases, the mink get pushed out of the ground.”
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“This is a natural process. Unfortunately, one meter of soil is not just one meter of soil — it depends on what type of soil it is. The problem is that the sandy soil in West Jutland is too light. So we have had to lay more soil on top,” the spokesperson added.
Overall, there are between 15 and 17 million minks on about 1,100 farms in Denmark.
“It is very, very serious,” Frederiksen said earlier this month, according to Reuters. “We have a great responsibility towards our own population, but with the mutation that has now been found, we have an even greater responsibility for the rest of the world as well.”
According to ABC News, it will cost Denmark — the world's largest producer of mink furs — up to 5 billion kroner ($785 million) to cull the country's 15 million minks.
A COVID-19 outbreak in mink population has also recently spread in the United States, specifically at fur farms across Wisconsin, Michigan and Utah.
Last month, a spokesperson for the Wisconsin Department of Agriculture, Trade and Consumer Protection confirmed to PEOPLE that more than 2,000 minks have died since animals at a farm in Taylor County tested positive for SARS-CoV-2, the virus that causes COVID-19 in humans.
The Michigan Department of Agricultural & Rural Development also announced last month that minks at one of the state's fur farms tested positive for SARS-CoV-2. In Utah, nearly 10,000 minks have died of COVID-19 at nine different fur farms, NBC News reported on Oct. 9.
"Minks show open mouth breathing, discharge from their eyes and nose, and are not sick for several days before they pass away," Utah veterinarian Dr. Dean Taylor told NBC News. "They typically die within the next day."
Minks were first discovered to be susceptible to SARS-CoV-2 in April when farms in the Netherlands suffered several outbreaks in its animal population, the Associated Press reported. Outbreaks among minks in Spain have since been detected.
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