A Danish vaccine specialist has warned that a new wave of coronavirus could be started by the Covid-19 mink variant.
“The worst-case scenario is that we would start off a new pandemic in Denmark. There’s a risk that this mutated virus is so different from the others that we’d have to put new things in a vaccine and therefore [the mutation] would slam us all in the whole world back to the start,” said Prof Kåre Mølbak, vaccine expert and director of infectious diseases at Denmark’s State Serum Institute (SSI).
He added, however, that the world was in a better place than when the Covid-19 outbreak began.“We know the virus, have measures in place including testing and infection control, and the outbreak will be contained, to the best of our knowledge.”
Denmark, the world’s largest mink producer, said on Wednesday that it plans to cull more than 15 million of the animals, due to fears that a Covid-19 mutation moving from mink to humans could jeopardise future vaccines.
Announcing the cull, the country’s prime minister, Mette Frederiksen, said 12 people were already infected with the mutated virus and mink are now considered a public health risk, based on advice from the SSI.
Prof Allan Randrup Thomsen, a virologist at the University of Copenhagen, went further, telling the Guardian on Thursday that while Denmarkwas not “on the verge of being the next Wuhan” there were risks.
“This variant can develop further, so that it becomes completely resistant, and then a vaccine does not matter. Therefore, we need to take [the mutation] out of the equation. So it’s serious.”
In interviews with Danish media, Thomsen advised shutting down northern Denmark due to the risks from mink farms, a task made easier by the Limfjord, which cuts across northern Jutland.
Although bridges across the fjord remain open, all restaurants, pubs, cafes and sports activities in the area will close shortly.
A Dutch virologist and zoonosis expert, Wim van der Poel, said more research was needed but that even without the mutation, a reservoir of the virus in mink or others of the mustelid family such as badgers and martens was to be avoided.
“It seems the mink-variant mutation is found in the spike protein of the Sars-Cov-2 virus, but we don’t really know. And we don’t know what kind of vaccine we are going to have. So a lot more research is needed,” said Van der Poel.
But even without a mutation, the continuing circulation within mink herds may pose a risk to humans. “We assume [this] is a risk too in the Netherlands, but our fur farming is being phased out already. There’s no more fur production now after the end of this year,” he said.
Van der Poel is currently looking at the effect of Covid-19 spreading to mustelids, a family of carnivorous mammals including weasels, badgers, otters, ferrets, martens and wolverines, among others. “ If that happened, then you have a reservoir in our local wildlife, and we could get reinfected before we even get a good quality vaccine.”
Prof Ian Jones, a virologist at the University of Reading, said: “The idea that the virus mutates in a new species is not surprising as it must adapt to be able to use mink receptors to enter cells and so will modify the spike protein to enable this to happen efficiently.
“The danger is that the mutated virus could then spread back into man and evade any vaccine response which would have been designed to the original, non-mutated version of the spike protein, and not the mink-adapted version. Of course, the mink version may not transmit well to man, so it’s a theoretical risk but Denmark is clearly taking a precautionary stance in aiming to eradicate the mink version so that this possibility is avoided or made much less likely.”
Jussi Peura, research director of the Finnish Fur Breeders’ Association and animal geneticist, was more sanguine. He said he understood the worry in Denmark, but felt the decision to carry out a cull might have been too extreme.
Instead, he suggested continuing with the control measures that were working in Finland.
“Right now we have zero cases in fur farms in Finland. We have a total of about 700 fur farms and of those about 150 are mink, all Covid-19-free so far.”
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