Europe’s coronavirus crisis is resurging. For months, 3 Nordic nations kept it under

Politicians are desperate to find a balance of restrictions that flatten the curve without flattening the economy or upsetting residents who are eager to reunite for the holidays.

“The key question now is to determine what is the optimal package of policies to maximize the health benefit at least cost,” said Thomas Hale, an associate professor of public policy at the University of Oxford. “However, this ‘magic formula’ will likely differ across different countries and populations, and of course over time as the virus surges or recedes.”

It’s a complicated and ever-changing calculus, and every country is different.

But the approaches of three nations — Finland, Norway and Denmark — in recent months stand out, a CNN analysis shows. The analysis, which looked at data from the University of Oxford and Johns Hopkins University, found that while all three countries implemented some of the continent’s most relaxed combinations of restrictions, they still managed to keep average daily deaths low — below one per million — for the three-month period between September 1 and November 30.

Denmark success may be ending. In late November, Danish death rates exceeded one per million for the first time since May, Johns Hopkins data shows. On Friday, the number of newly reported cases topped 4,000. Earlier in the week, officials expanded restrictions and announced a nationwide lockdown aimed at tamping down rising infections.

But what led to the three nations’ success in the fall?

Denmark, Finland and Norway responded quickly to the slightest increase in infections, which allowed them to almost eradicate the virus during the summer and face the autumn from a stronger place, according to interviews with six scholars. Clear guidance and residents’ willingness to follow it was also key, the experts said. And ramping up testing and contact-tracing capacities and providing paid sick leave helped to keep any outbreaks localized.

How to be the best (or how to be Finland)

Finland had Europe’s lowest average of infections and deaths per capita in recent months, Johns Hopkins data shows. It managed to contain local outbreaks while sticking to some of the most relaxed restrictions on the continent. Internal movement was not restricted, those who needed to could attend school and workplaces in person, and mask-wearing was not mandatory.

“There is nothing magical about doing this — we just have a pragmatic approach,” said Pekka Nuorti, an epidemiology professor at Tampere University who has worked for public health agencies for more than 25 years.

Cultural, political and geographic factors — such as low population density, less travel and high trust in government — were helpful, Nuorti said, but it was the work of the country’s health agencies that made a difference.

During the summer, Finland built up “tried-and-true field epidemiology practices,” Nuorti said: Testing, isolating, contact tracing, quarantining and preventing superspreading events on a local level.

The average daily testing volume nearly quadrupled from 2,900 samples in May to 11,300 in August, health ministry data shows. In late November, Finnish laboratories performed up to 23,000 tests a…