The surge in testing capacity came just in time. Patient 31 was about to figure into the country’s first known superspreader event, which would stretch Korea’s ability to rapidly test for Covid-19, trace the contacts of infected people, and isolate them.
On February 17, the patient, a woman in her 60s, tested positive for Covid-19 and was interviewed about her recent movements. Korean officials quickly realized they had a crisis in the making.
The woman had traveled between Seoul and Daegu, the country’s fourth-largest city, in the days before testing positive. She also attended services at the Shincheonji Church of Jesus, an insular Christian group based in Daegu.
Park Young-joon, as the head of epidemiological investigations at the KDCA, was quickly dispatched to Daegu. The government set up testing centers all across the area, including drive-through sites that could perform three times as many tests as regular clinics. After public pressure, the church group handed over a list of its members for contact tracing. Conscripted military personnel were called in to help.
Within days, hundreds of church members had tested positive. Park Young-joon decided the best way to contain the outbreak was to isolate everyone who may have been exposed. Thousands of people, tracked down through security footage and phone data, were urged to self-quarantine. The government struck a deal with Samsung and LG to transform their training dormitories into isolation centers for people deemed at higher risk. Noncompliance came with a hefty fine: more than $8,000 US.
The call went out to nurses like Jo Hye-min, pleading for volunteers to staff the isolation centers. More than 3,000 patients would enter the facilities during the month of March.
The country’s outbreak quickly leveled off. After averaging more than 500 new cases every day during the first week of March, the rate of daily new cases slowed dramatically. Over the first week of April, South Korea saw about 500 new cases total.
“We did an impossible task,” Jo says. “It was as though we built the Great Wall in a week.”
But Covid-19 wasn’t gone.
The next big scare arrived a month later, in early May: a cluster of infections linked to the Itaewon nightclub district. The clubs had reopened on April 30 — and by May 6, several cases were confirmed among people who had partied at one of them.
Jang Hanaram, a member of the military doing contact tracing work in Seoul, was put on the case. Jang says he was soon working 24 hours a day while sleeping in the bunk bed in his office. His days were a blur of phone interviews: He estimates that at the height of the effort, he was making more than 200 calls without a break.
Tracing contacts from the Itaewon outbreak added an extra degree of difficulty: Some of the nightclubs were favored by the LGBTQ community. There is still a lot of discrimination against LGBTQ people in South Korea, and people were not always forthcoming about where they’d been and whom they’d been in close contact with for fear of being outed or outing others.
One man, Jang says, lied to him during a contact tracing interview. But he and his team had other options. He could pull the man’s credit card and GPS data instead.
“Even when people weren’t so cooperative, we can find out where this person went and when,” Jang says.
By the end of May, using cellphone location data, South Korean authorities had identified nearly 60,000 people who had spent at least 30 minutes in the vicinity of the Itaewon nightclubs between April 30 and May 6.
Those people were simply urged to get tested. But another 1,200 deemed to be at higher risk of exposure were required to self-quarantine while being monitored by the government. Those patients checked in with health workers over a smartphone app; the government also sent them groceries and toiletries, and offered them psychological counseling.
Ultimately, the Itaewon cluster was linked to just 246 cases, and overall caseloads stayed well below what was seen in Daegu. The country didn’t see a second significant wave until late August, ignited by the protests of another church group.
But the extraordinary phone surveillance required to identify the 60,000 possible contacts in Itaewon has come under scrutiny from civil rights advocates, who saw some of their fears about the powers granted to the government in 2015 coming true.
“This was not the use envisioned by the people who passed the law after the MERS outbreak,” Park Kyung-sin says.
Privacy advocates worry about how much information the government can get — but it’s a “lonely fight”
South Korea’s epidemic response is distinct from that of the US and almost every other country in the world in one important way.
In the US, disease investigators must rely on interviews and, in theory, opt-in phone tracking apps, though those have struggled to attract enough users to be effective. In South Korea, cooperating with contact tracing isn’t done out of altruism, though everybody we spoke to stressed that South Koreans do feel a strong sense of civic responsibility. It’s the law — and if you refuse to comply, the authorities can get your financial or location data anyway. No such legal obligation exists in the US.
“The right to collect and use very personal information was an essential part of the  legislation,” Park Young-joon says.
South Korea’s government has stretched that authority as far as it can go during the current emergency — beyond what is legally permissible, according to some civil rights lawyers we spoke with.
During the Itaewon outbreak, for example, the public health authorities didn’t just notify the people who had come into close contact with the patients who later tested positive. They used phone location data to alert anybody who was in the area of their potential exposure, which South Koreans focused on privacy rights saw as a serious overreach.
Park Kyung-sin explains the difference with an analogy about how police might investigate a crime: Normally, investigators get a warrant to follow specific people, targeting specific phone numbers.
But what South Korea did in Itaewon, he says, was more comparable to the National Security Agency surveillance exposed by Edward Snowden. Anybody who was within a certain area, no matter the individual risk of exposure, had their location data scooped up by the government.
“When that’s done against your consent, that is a problem,” Park Kyung-sin says. “We are not really fighting the law but the use of the law.”
One man who lied to contact tracers after the Itaewon outbreak was a teacher who worried about the consequences if people found out he was gay. Because he misled investigators, he was arrested and sentenced to six months in jail.
A couple of months after the Itaewon outbreak, Park Kyung-sin and his colleagues at Open Net Korea filed a constitutional challenge against the government’s use of the 2015 laws, asking for restrictions on mandatory location tracking and clear commitments from the government about deleting information.
And yet, broadly speaking, the public has accepted the measures. About nine in 10 South Koreans said in May 2020 that they supported disclosing patient location information. Attitudes may be changing as the pandemic drags on — Park Young-joon said he and his colleagues have noticed a decline in support — but most people continue to comply.
“Most Koreans are willing to compromise their privacy for their life,” Kelly Kim at Open Net Korea, the civil rights group, says. For privacy advocates, “it’s been a really hard fight, a kind of lonely fight.”
South Korea’s system worked because it acted early
South Korea’s citizens don’t regard the country’s response as perfect. They have endured their share of strife.
Park Jeong-uk, a pub owner in Seongnam, saw his monthly revenue drop by 50 percent during a small wave of cases in August. A winter surge that necessitated more social distancing measures was even harder. He had to let two part-time workers go, and has taken out bank loans he’ll have to start paying back soon. He lost a lot of sleep.
But he’s feeling pretty optimistic these days.
“Despite the shortcomings, I agree the Korean government did their best, given the circumstances,” Park Jeong-uk says. “And Koreans did an excellent job cooperating with the government. Most people trusted the government and followed the protocols.”
In some ways, South Korea simply may have lucked out. It is almost like an island, sharing only a militarized land border with North Korea, making it easier to isolate and monitor incoming travelers. Its people were better acquainted than most with social distancing measures, having lived through MERS. There is generally a lot of government surveillance that may have inured people to their private actions being fodder for public health monitoring.
Contact tracing alone isn’t a panacea. The US struggled on the first step in the test-trace-isolate process, when the first CDC testing kit failed, and that allowed the virus to spread undetected. By the time testing was closer to adequate levels, infections were so widespread it would have been extremely difficult to conduct comprehensive contact tracing, especially without the extraordinary tools available in South Korea.
Testing, tracing, and isolating is a good way to put out small fires, as the preferred metaphor among epidemiologists goes. Once the whole forest is ablaze, it loses its utility.
But that is also the point. South Korea saw a small fire spring up in Daegu in February 2020 and focused the full power of the government on stamping it out — then watched to ensure no new sparks would create a conflagration. Those efforts succeeded.
“We’ve been training for this,” Jang Hanaram says. “We are in this together; our community comes first. Koreans have really stepped up.”
Jun Micheal Park is a documentary photographer and filmmaker from Seoul. He has extensively covered South Korea’s Covid-19 response.
This project was supported by the Commonwealth Fund, a national private foundation based in New York City that supports independent research on health care issues and makes grants to improve health care practice and policy.