On the second day of Christmas 2020, the Swedish Public Health Agency announced that the first case in Sweden of the British virus variant had been found in Sörmland.

Since then, the British variant has grown rapidly and steadily and has now gained a foothold throughout the country.

Not all confirmed corona cases are tested for the mutations, but among the cases tested for the mutations, the British variant is now dominant throughout the country.

The Swedish Public Health Agency's latest compilation from week 11 with figures from 18 regions indicates that the variant accounts for over 70 percent of the covid cases analyzed in 14 regions.

- It is striking that weeks 5 and 6 these figures were below 20 percent, so it has been extremely fast for this variant to establish itself, says Tove Fall, professor of molecular epidemiology at Uppsala University, in SVT's Aktuellt.

- This variant is more contagious, and there are studies from the UK and Denmark that show that you need hospital care more often, says Tove Fall.

Almost completely dominant in some places

The largest distribution is in Jönköping with 92 percent.

In Gävleborg, the same figure is 89 percent, and in Västernorrland and Örebro 86 percent.

In Stockholm, the prevalence is 84 percent.

Of the regions surveyed by the Swedish Public Health Agency, Norrbotten has the lowest figure with 45 percent.

It is the regions' so-called typing of positive test results that has been compiled by the Swedish Public Health Agency.

Typing is a new method where a simpler analysis is made of the test results instead of, as traditionally, looking for special mutations in the gene sequence.

Other variants are gaining ground

The South African and Brazilian mutation variants have also come here.

They are most widespread in Värmland, where they account for 16 percent, according to current figures from the Swedish Public Health Agency.

In Dalarna, these variants account for 11 percent and in Uppsala and Västmanland 10 percent, the figures show.

In many regions, however, these varieties are still rare.