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A GROUP OF young people sit around a table in a bar, immersed in animated conversation. A man and a woman sit in the window of a coffee shop and share bites of a large slice of cream cake. A handful of people in face masks and office attire emerge from a side street and say their goodbyes before disappearing down the stairs into the subway station. In normal times such scenes would hardly merit a mention. But when a third of the world’s population is living under lockdown, the relative normality of Seoul feels surreal.

That life in South Korea has not ground to a complete halt is mostly owing to an early and aggressive response to the covid-19 pandemic. The country’s disease-control authority approved the first test kit for the virus in early February, less than a week after the application was filed. By the time the number of cases began to rise a couple of weeks later, it had the capacity to test thousands of people a day and get results within a few hours from a network of labs across the country.

This was invaluable when an enormous cluster of cases emerged in the city of Daegu, centred around a messianic cult. Members of the Shincheonji church pray crammed together for hours during their services, providing an ideal environment for the new coronavirus to spread. Of the country’s 9,661 currently confirmed cases, more than half are linked to the cult. Its founder claims to be descended from Korean kings and to possess the ability to foresee the apocalypse. Luckily for Korean officials, his group also kept meticulous records. Working off a membership list provided by the cult, the virus detectives managed to track down its more than 200,000 members, including 10,000 followers in Daegu. Those with symptoms of the virus were tested and, if positive, taken to hospital or confined to quarantine facilities.

Besides interviewing patients, officials used location data from mobile phones, credit-card transaction records and CCTV footage to trace and test people who might have crossed paths with an infected person. In many places, they published detailed maps of the movements of patients and encouraged people who thought they might have been in contact with one to seek out testing. Overall, the country has tested nearly 400,000 people for the virus in less than two months, one of the highest rates of testing in the world. In parallel, South Koreans were advised to wash their hands frequently, avoid unnecessary outings, keep away from other people when out and about and wear masks on public transport and in other closed spaces.

In combination, those measures slowed the spread of the virus sufficiently that South Korea did not have to resort to the more coercive lockdowns that America and many European governments have implemented over the past few weeks. South Korea has registered around 100 new cases every day for the past three weeks, with only occasional spikes, and a total of 158 deaths. In contrast Spain and Italy, countries of similar population which were hit later than South Korea, have about ten times more cases and roughly 7,000 and 11,000 deaths respectively.

As a result, South Korea’s health-care system is coping. Though hospitals in Daegu were briefly overwhelmed at the height of the outbreak in late February, this was quickly resolved by treating those with mild symptoms in residential centres rather than hospitals, easing the pressure on wards.

The main reason that South Korea responded so quickly to the initial outbreak is its recent bad experience with MERS, another coronavirus, which killed 38 people in the country in 2015. “We were hit hard by MERS because we failed to supply diagnostic kits in time,” says Hong Ki-ho, director of laboratory medicine at Seoul Medical Centre and a member of the country’s covid-19 taskforce. In response, South Korea increased diagnostic capacity, hired more epidemiological investigators and changed the law to improve information-sharing between different branches of government and the health-care system and to allow fast-track approval of test kits during an outbreak.

Widespread testing will probably help the country manage its outbreak over the next few weeks, even if, as is likely, new clusters of the virus continue to emerge all over the country. But the government clearly worries that it will not be enough. Over the past few days, it has introduced more draconian measures to curb the growing number of imported cases, including compulsory tests for arrivals from Europe and America. From April 1st, all travellers arriving from abroad will be obliged to undergo two weeks of quarantine either at home or in a government facility. Only diplomats and those on official business will be exempt. Breaking quarantine carries a fine of 10m won ($8,170) and up to a year in prison for Koreans. Foreigners risk deportation. Chung Sye-kyun, the prime minister, made it clear that the point of the measures was to close off the country for the time being: he said the policy was intended to “effectively block all unnecessary arrivals”.

In the short term, the move is likely to help keep the numbers low. But eventually South Korea, like all other countries in the world, will have to think about when and how quickly to relax the current controls. For all the relative freedom its citizens currently enjoy compared with Europeans and Americans, life is hardly back to normal. Schools, museums and gyms—places where large numbers of people might gather in an enclosed space—remain closed. Churches have moved worship online. As people are still encouraged to avoid unnecessary outings, cinemas have begun to close for lack of customers, as have many bars and restaurants. If the cases multiply, the country may have to toughen social-distancing rules. Dr Hong believes that for now, continuing to trace infections aggressively remains the most important measure. “Until there is a vaccine, we have to stay vigilant.”

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