Public health authorities in Denmark and Norway on Monday released grim projections for the coming wave of the omicron coronavirus variant, predicting that it will dominate both countries in a matter of days. Although scientists don’t yet know how often the variant causes severe disease, they say its rapid rate of spread will lead to an explosion of cases and could potentially increase pressure on hospitals, even if it proves to be mild.

The reports follow similarly worrisome findings from England released over the weekend, although researchers caution that the trend could change as the variant comes into clearer view.

It’s not yet certain how often omicron infections will send people to the hospital, or how many hospitalised patients are likely to die. And while omicron can partly evade immune defences, researchers have yet to determine how well vaccinations and previous infections will protect people against severe disease.

The authors of both new reports also observed that swift actions now, such as booster campaigns and reducing opportunities for omicron to spread, could lessen the variant’s impact.

American researchers have yet to release models of omicron’s rise in the US. But experts point out that the country is similar to Norway and Denmark in terms of vaccination levels and certain Covid risk factors, like the average age of the population.

“It would be naïve to think the US would be any different than Denmark,” Mads Albertsen, a microbiologist at Aalborg University, said. “Denmark is likely a best-case scenario.” In recent weeks, many epidemiologists have been paying close attention to Denmark, a country of 5.8 million residents, about the population of Wisconsin.

Early in the pandemic, the country set up a sophisticated surveillance system combining large-scale coronavirus testing with genetic sequencing of many samples. That strategy has allowed Denmark to spot newly emerging variants, even when they’re at low levels, and adjust public health policies to prepare for new surges.

The first omicron sample from Denmark was sequenced on December 3. The specimen was collected on November 23, around the same time researchers in South Africa first told the world about a rise in cases there.

Because sequencing genetic material from coronavirus samples can take days, Danish researchers developed a quick genetic test that picks up a few key mutations found only in omicron.

New York Times News Service