Each year thousands of minks escape from Danish fur farms, and with 5 percent of the farm minks infected with COVID-19, this means there could be hundreds of the diesease-carriers in the wild. Scientists have warned that the diseased mink could create a new uncontrollable store and vector for the transmission of coronvirus to humans.
Minks have been linked to a new strain of the virus that could pose a risk to future COVID vaccines. Efforts to cull infected mink in Denmark began in June but outbreaks at mink farms have continued.
Sten Mortensen, veterinary research manager at the Danish Veterinary and Food Administration, told The Guardian: “Every year, a few thousand mink escape. We know that because they are an invasive species and every year hunters and trappers kill a few thousand wild mink. The population of escaped mink is quite stable.”
This year there was a risk that around 5 percent of the escaped mink were infected with the virus, according to Mortensen.
The most likely method of transmission in the wild would be an animal eating an infected mink or via their feces, Mortensen noted. However, the risk of the escaped mink infecting other animals is low because mink are “very solitary creatures,” he added.
If the mink do spread the virus to other animals, those most likely to be infected include wild animals such as ferrets and raccoon dogs as well as “susceptible domestic animals” such as cats, according to Mortensen.
Scientists warned the escaped mink could broaden the infection range of the virus by introducing into the wild.
Joanne Santini, a professor of microbiology at University College London in the U.K. capital, told The Guardian: “The virus could broaden its host-range [and] infect other species of animals that it wouldn’t ordinarily be able to infect. It will become extremely difficult to control its further spread to animals and then back to humans.”
Marion Koopmans, head of the Erasmus Medical Center department of viroscience at Rotterdam’s Erasmus University in The Netherlands, told The Guardian: “Sars-CoV-2 could potentially continue to circulate in large-scale farms or be introduced to escaped and wild mustelids [weasels, badgers, otters, ferrets, martens, minks, and wolverines] or other wildlife.
“In theory, as avian flu and swine influenza viruses do, [the virus could] continue to evolve in their animal hosts, constituting a permanent pandemic threat to humans and animals,” Koopmans added.
Newsweek has contacted the Danish Veterinary Association and the Danish Ministry of Environment and Food for comment.
A mink at the Knud Vest estate in Jyllinge, Denmark, pictured on November 14. Ole Jensen/Getty Images
Dead mink culled in Denmark were reported to be rising from their graves last month as their bodies expanded during the decaying process.
The mink corpses were disinfected and covered with lime before burial, according to Thomas Kristensen, a spokesperson for Danish police who were deployed last month to help farmers cull millions of mink following the outbreak.
Kristensen noted the risk posed by the decomposing bodies was small because live mink mostly transmit COVID-19 by exhaling it into the air. But he warned that “small quantities of bacteria may still be trapped in their fur.”
On Friday, a mink farm in Oregon was immediately placed under quarantine after cases were reported among mink and staff, the Oregon Department of Agriculture (ODA) confirmed in a statement.
ODA state veterinarian, Dr. Ryan Scholz, said in the statement: “So far, we have no reports of mink mortalities linked to the virus but that could change as the virus progresses.”
The statement added: “The farm is also reporting cases of COVID-19 in staff. In response, Dr. Emilio DeBess, OHA public health veterinarian, recommended the farmer and staff self-isolate.”
The farm, the employees and their families will continue to be monitored by the ODA and OHA.
The ODA noted: “This year, the virus was detected in mink internationally in seven countries, including the Netherlands, Denmark, Italy, Sweden, Spain, and in the United States in Utah, Michigan, and Wisconsin. Other species of animals within the United States have tested positive for SARS-CoV-2.
“Per the CDC [U.S. Centers for Disease Control and Prevention] and USDA-APHIS [United States Department of Agriculture – Animal and Plant Health Inspection Service], there is currently no evidence that animals, including mink, play a significant role in transmitting the virus to humans. The risk of animals spreading SARS-CoV-2 to humans is considered low,” the ODA added.
The wider picture
The novel coronavirus has infected more than 63.3 million people since it was first reported in Wuhan, China.
More than 1.4 million people have died worldwide and more than 40.6 million have recovered as of Tuesday, according to Johns Hopkins.
The graphic below, produced by Statista, shows countries with the most COVID-19 cases.
The graphic below, produced by Statista, shows the total number of COVID-19 vaccine doses secured by different countries.