Most of the world found itself confined to their homes in March 2020 as Covid-19 spread at a blistering pace. Some countries didn't impose any lockdown restrictions – so was their decision the right one?

In March 2020, billions of people stared out through their windows at a world they no longer recognised. Suddenly confined to their homes, their lives had shrunk abruptly to four walls and computer screens.

Around the world, national leaders appeared on television, telling them to stay put – only leave the house to buy essential supplies or for once-daily exercise, maybe. It was a last-ditch attempt to curb the spread of a terrifying virus that had already killed many thousands of people worldwide.

In London, theatre worker Tony Beckingham and his partner decided to use their daily exercise to cycle into the centre of the city one evening. "We thought it'd be really fun to see no-one around," he says. It wasn't. Places the pair knew well, like Piccadilly Circus and Leicester Square, perennially abuzz with people, were chillingly quiet. "It was really upsetting – instantly," says Beckingham.

This deletion of the public from city streets, venues and businesses first began in China, where Covid-19 emerged. Quarantine orders were soon replicated in other countries after the World Health Organization (WHO) declared a pandemic on 11 March 2020. At no prior point in human history have people faced restrictions like this on such a scale.

But a handful of countries did things differently. Sweden, Taiwan, Uruguay, Iceland and a few others never enacted a lockdown that involved severe restrictions on the movement of people, such as legally binding stay-at-home orders applied across large swathes of the population. Those countries instead chose other measures, such as restrictions on large gatherings of people, extensive testing and quarantining infected people or travel restrictions.

Five years later, the scientific studies and data have piled up, offering a detailed, long-term assessment of whether these countries were right to reject this most drastic of public health interventions.

The Swedish city of Gothenburg is a haven for dog-lovers, says HR administrator and blogger Anna Mc Manus, "We have a very dog-friendly city here," she says. "We even have a dog-friendly cinema." As countries around the world, including Sweden's neighbours Norway, Finland and Denmark, ushered in national lockdowns in March 2020, Mc Manus was aware that her own government had decided to buck the trend.

She heard how dog owners in some nations couldn't even take their pets out for walks because of lockdown rules. South Africa was one such country. This struck Mc Manus as terrible. At the time, she wrote a blog post in which she said, "I am convinced that my government is acting in a secure and correct way". However, she also expressed concern that her fellow Swedes were not always following the official public health guidelines around social distancing, such as limiting the number of people who could meet together in a group.

Mc Manus remembers taking frequent walks in beauty spots, but also that she and her colleagues continually wore masks to help prevent Covid-19 transmission at the veterinary hospital where she worked in 2020. Plus, she and her partner avoided restaurants and meeting up with lots of other people. Even now, Mc Manus says she is not sure what to make of Sweden's official strategy.

"I want to base it on facts – like how many people died," she says. "Could we have saved a lot more people if we had had a lockdown?"

Scientists have tried to answer that question. Ingeborg Forthun at the Norwegian Institute of Public Health and researchers in other countries including Sweden published a study in May 2024 that compared excess deaths in Sweden, Norway, Denmark and Finland during the first years of the pandemic.

While Sweden avoided strict government imposed controls, instead relying mainly on voluntary behavioural changes from is citizens, the other three nations imposed strict lockdowns in the early stages of the pandemic. Norway, Finland and Denmark closed schools and most other aspects of public life while also asking people to work from home, but they stopped short of confining people to their homes in the way other countries such as the UK did.

Perhaps unsurprisingly, the researchers found a noticeable spike in excess deaths in Sweden during the initial waves of the pandemic during the spring and winter of 2020, when Covid-19 was able to spread more freely than in neighbouring nations. But while excess mortality fell in the three other countries in 2020, it rose compared to Sweden in 2021 and 2022.

"The four countries have a comparable number of excess deaths when you account for the fact that population sizes differ," says Forthun. What lockdowns did affect, in part, was the timing of when spikes in excess deaths occurred. Of Norway's approach, Forthun adds: "We probably kept some older and vulnerable people alive for a longer period." Whereas authorities in Sweden were criticised in 2020 over high numbers of deaths at care homes.

Some economists have combined similar data with comparisons of economic performance indicators between the same four Nordic countries to argue that, overall, Sweden's approach was justified due to the relatively low economic costs. But such arguments are controversial and the lack of a lockdown in Sweden remains an area for heated debate among some.

Another study by a group of German economists – who modelled how a lockdown could have affected pandemic outcomes in Sweden – suggests that the substantial voluntary restraints enacted by people in the country appear to have replicated some of the effects of a lockdown anyway.

One Swedish epidemiologist, Nele Brusselaers, of........

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