Coronavirus: Should we be concerned about the mutation of the COVID-19 virus in mink?

The Danish Executive said in September that it would exterminate 17 million minks after a dozen people were infected by a new Sars-Cov-2 mutation in North Jutland. Eight of them from the fur industry, and the rest from nearby communities.

It was not the first time that the mink had contracted the virus and transmitted it to humans. In April 2020, a farm worker at a mink farm in the Netherlands was diagnosed with COVID-19 and it was later shown that both human-to-mink and mink-to-human transmission can occur. In the following months, mink infections have been reported in Italy, Spain, Sweden, and the United States.

The difference in Denmark was that the COVID-19 detected in mink and the humans they infected came from a mutation of the virus, suggesting that even when pharmaceutical companies appear to be on the verge of a vaccine against, new strains may be evolving. , potentially more dangerous.

According to the European Center for Disease Control (ECDC), the virus that causes COVID-19 has mutated at least 20 times since it was first detected in humans in 2019. Most of these mutations have had little effect on the virus and some have even weakened it, according to a sample taken in October 2020.

But when a virus changes from one species to another, the mutations can be more severe. The virus adapts and develops in a new host with a different biological and genetic makeup. When transmitted back to the original species, it can be a stronger and more resistant virus.

This means that if you have immunity to one strain of the virus that causes COVID-19 – through a vaccine, for example – but then contract another strain that has mutated into a different species, you may not have immunity to this new type.

What is the good new?

Although the new strain has mutated, scientists still don’t know if that means the virus is more deadly.

In fact, the ECDC notes that although the strain is different, genetically, patients infected with mink-related variants do not have worse symptoms than those with non-mink-related COVID-19. Likewise, Mink farming is a relatively small sector of the global agricultural industry and mink is unlikely to spread COVID-19 en masse across borders.

In its conclusions, the ECDC says that the overall risk to human health in the general population is low, while for those working in mink farming it is moderate.

Similarly, while the outbreak in Denmark has been severe, in August a single mink was discovered in Italy to have contracted COVID-19 and, although 1,500 of its fellow minks were tested, none were found to have contracted the virus .

Meanwhile, in the Netherlands, the outbreak led to the country’s mink farming ban being pushed forward from January 2021 to January 2024, which will be welcomed by rights advocacy groups. animals.

And the bad news?

The mink variant has raised concerns about its effect on antigenicity, that is, the ability to induce an immune response. Since vaccines try to induce immunity, the fear is that COVID-19 vaccines do not protect against this strain of the virus.

The worst case scenario is that multiple new strains develop from animal-to-human and human-to-animal transmission, which in theory could require multiple vaccines. Given the time it takes to develop a vaccine, the fear is that COVID-19 will keep mutating and will never go away.

But – and it’s a big “but” – there is currently no evidence that this new strain is less susceptible to the vaccines currently being developed.

Why the mink?

The animals most susceptible to SARS-CoV-2 are cats, lions, tigers, ferrets, mink and two species of hamster and bat, the Egyptian fruit bat and the golden Syrian hamster.

Mink comes from the same family as ferrets, which as early as the mid-1930s have been used by scientists to study flu viruses and, more recently, to test flu vaccines and antivirals.

The reason ferrets make good subjects is that, unlike mice, which are often used as test subjects by scientists, they display symptoms similar to humans, such as fever and sneezing.

But the reason why COVID-19 spread so rapidly among minks in Denmark is probably due to the intensive nature of the industry, which involves keeping hundreds of animals in steel mesh cages and in close proximity to each other.

Europe is the world leader in fur production, with more than 27 million mink pellets produced annually and more than 2,750 farms, 1,100 of them in Denmark.