Sweden's health agency said on Thursday a number of people who work in the mink industry had tested positive for the coronavirus.
Authorities are analysing virus from the infected people and from infected minks to see if there is a link between the strains, the health agency said in a statement.
It did not specify how many people had tested positive.
Neighbouring Denmark earlier on Thursday said a new, mutated strain of the coronavirus stemming from mink farms in the country was "most likely" extinct.
All farmed minks in Denmark have been culled because of coronavirus outbreaks among the animals and the discovery of the mutated strain, which authorities said showed reduced sensitivity to antibodies, causing fears it could compromise vaccines.
Sweden's mink herd is vastly smaller than Denmark's, which was one of the world's biggest.
In common with countries such as the United States, Sweden has recorded the coronavirus at several farms although authorities have said the minks had not been found to carry the mutated strain evident in Denmark.
(Reporting by Anna Ringstrom; Editing by Simon Johnson and Barbara Lewis)
