Denmark is dominated by a new subvariant of the omicron strain of the novel coronavirus, named BA.2,
In the second week of 2022, BA.2 accounted for 45% of new infections in Denmark.
A similar situation is observed in Norway and the United Kingdom.
The Danish health authorities believe that existing vaccines can protect against severe disease.
Danish researcher Anders Fomsgaard said that people who recovered from BA.1 would have weakened immunity to BA.2 and were more likely to get sick again.