By Michael Birnbaum,
Tim Kildeborg Jensen AFP/Getty Images
Denmark was among the first countries to sound the alarm about the difficulty of controlling the spread of the new more transmissible variant of the coronavirus first identified in Britain. But new data suggests the country may have curbed this more contagious mutation, at least temporarily.
Danish authorities released a new estimate of the spread of the strain of the coronavirus, saying that as of Feb. 1, they believed that every person who was infected with the B.1.1.7 lineage was passing it along to 0.99 other people. That would be a significant drop from previous estimates that suggested that the variant was spreading among Danes at a rapid pace despite an extensive national lockdown.
The new estimate means that Danish authorities believe the strain was staying constant at the beginning of the month, neither shrinking nor growing within society.
“Although it is positive that the contact number is now around 1, the development must be interpreted with caution, as there may be variation over time, and it is too early to assess whether there is a stable trend,” Denmark’s State Serum Institute, the public health agency charged with monitoring the spread of the virus, said in a statement.
Danish officials previously estimated that each person infected with the new mutation was passing the virus to about 1.1 people, a situation of rapid growth.
Although officials said the reprieve may be only temporary, the leveling-off of caseloads of the variant was still a positive sign that it may be possible to control the more contagious mutation as vaccines are rolled out across the world. Because of the variant, Denmark is now observing a tight lockdown. Most businesses are closed, people have been ordered to work from home, restrictions have been imposed on international travel, and most schools are shuttered, even though overall coronavirus cases have dropped sharply to about a 10th of their mid-December peak.
Denmark is one of the world’s leaders in genetic monitoring of viruses, giving it a window into the spread of mutations, a detailed view that most countries do not have.
Primary schools were partly reopened on Monday after being closed to in-person instruction since the winter holidays. Overall cases in Denmark have dropped sharply during the lockdown, but Danish authorities said that was, in effect, an illusion, with the more contagious variant of coronavirus growing under the seemingly tranquil surface and poised to break through.
“Although the numbers on the surface look good in Denmark, the British mutation is simmering just below and will soon be the dominant one,” Danish Prime Minister Mette Frederiksen told reporters on Monday as she visited a newly reopened school. “So we cannot do a major reopening in Denmark, although of course we would like to.”
As of last week, the variant accounted for 27 percent of all coronavirus infections in the country, up from 20 percent the previous week, and researchers expect it will overtake previous mutations within weeks. But the slowed transmissions have bought the country some time.
The growth was visible in a separate estimate of the country’s overall viral reproduction rate released Tuesday. The rate rose to 1, meaning that overall cases are staying flat rather than shrinking.
The rise “is not unexpected when the share of B117 grows and when we have the season against us,” Danish Health Minister Magnus Heunicke wrote on Twitter, noting the new data. “Now it is important that the number is kept at this level when B117 becomes dominant. So stick to good habits.”
The new data on the viral mutations, which was released Tuesday, covers the week up to Feb. 1. There is a delay because it takes time to sequence the genome of each positive case of the coronavirus.
Public health officials warned Danish media that preliminary analyses of data since Feb. 1 suggest that the new variant may again be increasing.