Finland has so far recorded 61 cases of new variants of Covid-19, with calculations suggesting that as many as 550 people could have been infected with the variants.
Health officials from the Helsinki region said at a press conference on Friday that quarantine rules need to be stricter, that the new variants are already in the country, and that testing rates have dropped.
By 13 January Finland had recorded 59 cases of the British variant of coronavirus and two of the South African mutation, according to Eeva Ruotsalainen of the Helsinki University hospital district which has seen more than half of the confirmed variant infections.
That means Finland could be approaching a turning point in the epidemic.
"Healthcare capacity will come under strain at the stage when the virus starts to spread among the population so much that it reaches the risk groups," said Ruotsalainen.
The mutations are highly contagious, with one infection chain showing that a single person had infected 28 others with the new variant.
She said that the variants are 50-70 percent more infectious than the previous strain, and that the figure of 61 was an undercount of the true picture.
Danish scientists have established a method of estimating the likely number of cases of the new strains. Some of the confirmed new variant cases could not be traced back to international travel.
"So if at this moment in Finland we have confirmed 61 infections, then we can multiply that by nine so we could at this moment have around 550 cases already in Finland," said Ruotsalainen.
Finland is now testing all positive samples taken at the border to be sequenced, in order to identify new variant cases.
Ruotsalainen says that all those exposed to new variant cases should be tested, and they should be quarantined for fourteen days — up from the current ten days for exposure to the original Covid strain.
If anyone in the household then falls ill with coronavirus, the quarantine period increases to three weeks.
HUS also said that the decline in case numbers had stopped. At the peak of the second wave in the autumn, some 1,600 cases every two weeks were recorded. That is now down to 900, but it is stable at that figure.
In addition, testing has fallen since Christmas. That means a higher proportion of tests are coming back positive.
"We're at a dangerously high level, we have to get this down," said Helsinki University hospital district Chief Physician Markku Mäkijärvi.
HUS has now given some 17,000 people a first dose of the coronavirus vaccine, according to Mäkijärvi.
He says HUS is aiming to administer 12-13,000 doses a week once mass vaccinations begin, and is aiming for that to happen in March, but availability of vaccines might hinder that timetable.
Meanwhile the Helsinki region coronavirus coordination group said on Friday that final year Upper Secondary students would be given the option of returning to contact teaching ahead of their exams, which start in March.
They are recommending that pupils undertake a fortnight's isolation before their exams.
Children's hobbies in indoor spaces will remain off the agenda in Helsinki, however, according to the group's decisions.