First of TS its Denmark not Scandinavian countries. Its one country.
Approx 214 people have been tested positive for this version of the virus.
Denmark was planning to put down all their 17 million minks but only put down 2.5 mil.
The virus mutate yes, but it will not become a new pandemic.
The farms and the areas are in lock downs not the whole country because of this mutation.
The municipals with the mink version are restricted
The same cluster was already found during the summer in minkfarms in Holland.
Thus mutation is not new it seems. And its also found in USA.
https://www.who.int/csr/don/06-november-2020-mink-associated-sars-cov2-denmark/en/