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 Denmark has placed seven towns in North Jutland into an emergency lockdown and ordered the culling of all the country's up to 17million minks in an effort to prevent any further spread of the strain.

Amid calls for borders to the nation to be closed, the UK and Germany have both added the country to their travel quarantine lists. And Nicola Sturgeon insisted Scotland was also considering whether any tougher action was needed.

Tests revealed when the virus jumped from humans into minks on fur farms its spike proteins - which allow it to invade cells - mutated to infect the animals more easily.

But when the virus was transmitted back into humans it carried this mutation with it, which scientists in Denmark claim makes Covid-19 antibodies less effective.

Antibodies are disease-fighting proteins made and stored by the immune system to fight off invaders in the future by latching onto their spike proteins. But if they are unable to recognise proteins because they have mutated, it means the body may struggle to attack a virus the second time and lead to a second infection.

Authorities have no proof the strain is any more contagious or deadly, insisting there is 'no reason to worry' and mutations happen all the time and are usually harmless.

Five different strains of mutant mink coronavirus have been spotted in 214 people in Denmark since June. Analysis by Denmark's State Serum Institute revealed only one of these - known as Cluster 5 - is less sensitive to antibodies.

It has been found in 11 people living in North Jutland - which has been placed under lockdown - and one person living in neighbouring Zealand. Of the five farms where it was identified, only three of them were linked to four people with the infection, suggesting the strain is spreading between humans in the community. 

https://www.dailymail.co.uk/news/article-8920593/Mutated-coronavirus-Danish-mink-spread-214-people-lockdown-announced.html

WHAT ARE THE MINK STRAINS AND WHY DO THEY MATTER?

Denmark has identified five variants of the virus stemming from mink, but only one - known as Cluster 5 - showed “reduced sensitivity” towards antibodies, according to Denmark’s State Serum Institute (SSI), which deals with infectious diseases.

State epidemiologist Kare Molbak said cluster 5 was not more dangerous than other strains or more infectious.

Clusters 2, 3 and 4 are still being studied for reduced sensitivity, which has already been ruled out in the cluster 1 variant.

HOW FAR HAS THE MUTATED VIRUS SPREAD?

Cluster 5 has been found on five mink farms in Northern Denmark and 12 cases were registered in humans in the same Danish region in August and September, but none has been registered since then, according to SSI.

“We can simply hope that it no longer exists to the same extent,” Molbak told a news conference on Thursday, adding that nothing could be said with certainty.

Cluster 5 makes up around 5% of the strains found in Northern Denmark, but it has not appeared outside the country and it was not immediately clear why it emerged in Denmark.

WHAT’S THE IMPLICATION FOR FUTURE VACCINES?

It’s too early to say what, if any, impact the cluster 5 mutation could have on the efficacy of potential vaccines, Soumya Swaminathan, the World Health Organization’s chief scientist, said on Friday.

But SSI’s initial laboratory studies show the new strain had mutations on its so-called spike protein, which invades and infects healthy cells.

This could pose a problem to future vaccines that are currently in development as most of them focus on disabling the spike protein.

Data have been shared with international counterparts, including the WHO and the European Centre for Disease Prevention and Control (ECDC), and the genome sequences of the mutated virus strains have been logged in the Global Initiative on Sharing All Influenza Data (GISAID).

SSI said it would continue to share its findings.

https://jp.reuters.com/article/us-health-coronavirus-denmark-mink-factb/factbox-what-we-know-about-denmarks-mink-coronavirus-strain-idINKBN27M2L4

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