Coronavirus
cases have dropped sharply in South Korea. What’s the secret to its success?
By Dennis NormileMar.
17, 2020
Europe is now the epicenter
of the COVID-19 pandemic. Case counts and deaths are soaring in Italy, Spain,
France, and Germany, and many countries have imposed lockdowns and closed
borders. Meanwhile, the United States, hampered by a fiasco with delayed and
faulty test kits, is just guessing at its COVID-19 burden, though experts
believe it is on the same trajectory as countries in Europe.
Amid
these dire trends, South Korea has emerged as a sign of hope and a model to
emulate. The country of 50 million appears to have greatly slowed its epidemic;
it reported only 74 new cases today, down from 909 at its peak on 29 February.
And it has done so without locking down entire cities or taking some of the other
authoritarian measures that
helped China bring its epidemic under control. “South Korea is a democratic
republic, we feel a lockdown is not a reasonable choice,” says Kim Woo-Joo, an
infectious disease specialist at Korea University. South Korea’s success may
hold lessons for other countries—and also a warning: Even after driving case
numbers down, the country is braced for a resurgence.
Behind
its success so far has been the most expansive and well-organized testing
program in the world, combined with extensive efforts to isolate infected
people and trace and quarantine their contacts. South Korea has tested more than
270,000 people, which amounts to more than 5200 tests per million
inhabitants—more than any other country except tiny Bahrain, according to
the Worldometer website. The United States has so far carried out 74 tests
per 1 million inhabitants, data from the U.S. Centers for Disease Control and
Prevention show.
South
Korea’s experience shows that “diagnostic capacity at scale is key to epidemic
control,” says Raina MacIntyre, an emerging infectious disease scholar at the
University of New South Wales, Sydney. “Contact tracing is also very
influential in epidemic control, as is case isolation,” she says.
Yet
whether the success will hold is unclear. New case numbers are declining largely
because the herculean effort to investigate a massive cluster of more than 5000
cases—60% of the nation’s total—linked to the Shincheonji Church of Jesus, a
secretive, messianic megachurch, is winding down. But because of that effort,
“We have not looked hard in other parts of Korea,” says Oh Myoung-Don, an
infectious disease specialist at Seoul National University.
New
clusters are now appearing. Since last week, authorities have reported many new
infections, including 129 linked to a Seoul call center. “This could be the
initiation of community spread,” through Seoul and its surrounding Gyeonggi
province, Kim says. The region is home to 23 million people.
Lessons from MERS
South
Korea learned the importance of preparedness the hard way. In 2015, a South
Korean businessman came down with Middle East respiratory syndrome (MERS) after
returning from a visit to three Middle Eastern countries. He was treated at
three South Korean health facilities before he was diagnosed with MERS and
isolated. By then, he had set off a chain of transmission that infected 186 and
killed 36, including many patients hospitalized for other ailments, visitors,
and hospital staff. Tracing, testing, and quarantining nearly 17,000 people
quashed the outbreak after 2 months. The specter of a runaway epidemic alarmed
the nation and dented the economy.
“That
experience showed that laboratory testing is essential to control an emerging
infectious disease,” Kim says. In addition, Oh says, “The MERS experience
certainly helped us to improve hospital infection prevention and control.” So
far, there are no reports of infections of COVID-19 among South Korean health
care workers, he says.
Legislation
enacted since then gave the government authority to collect mobile phone,
credit card, and other data from those who test positive to reconstruct their
recent whereabouts. That information, stripped of personal identifiers, is
shared on social media apps that allow others to determine whether they may have
crossed paths with an infected person.
After
the novel coronavirus emerged in China, Korea Centers for Disease Control and
Prevention (KCDC) raced to develop its tests and cooperated with diagnostic
manufacturers to develop commercial test kits. The first test was approved on 7
February, when the country had just a few cases, and distributed to regional
health centers. Just 11 days later, a 61-year-old woman, known as “Case 31,”
tested positive. She had attended 9 and 16 February services at the Shincheonji
megachurch in Daegu, about 240 kilometers southeast of Seoul, already feeling
slightly ill. Upward of 500 attendees sit shoulder to shoulder on the floor of
the church during 2-hour services, according to local news reports.
The
country identified more than 2900 new cases just in the next 12 days, the vast
majority Shincheonji members. On 29 February alone, KCDC reported more than 900
new cases, bringing the cumulative total to 3150 and making the outbreak the
largest by far outside mainland China. The surge initially overwhelmed testing
capabilities and KCDC’s 130 disease detectives couldn’t keep up, Kim says.
Contact tracing efforts were concentrated on the Shincheonji cluster, in which
80% of those reporting respiratory symptoms proved positive, compared with only
10% in other clusters.
High-risk
patients with underlying illnesses get priority for hospitalization, says Chun
Byung-Chul, an epidemiologist at Korea University. Those with moderate symptoms
are sent to repurposed corporate training facilities and spaces provided by
public institutions, where they get basic medical support and observation.
Those who recover and test negative twice are released. Close contacts and
those with minimal symptoms whose family members are free of chronic diseases
and who can measure their own temperatures are ordered to self-quarantine for 2
weeks. A local monitoring team calls twice daily to make sure the quarantined
stay put and to ask about symptoms. Quarantine violators face up to 3 million
won ($2500) fines. If a recent bill becomes law, the fine will go up to 10
million won and as much as a year in jail.
In
spite of the efforts, the Daegu-Gyeongbuk region ran out of space for the
seriously ill. Four people isolated at home, waiting for hospital beds, were
rushed to emergency rooms when their conditions deteriorated, only to die
there, according to local media.
Still,
the numbers of new cases have dropped the past 2 weeks, aided by voluntary
social distancing, both in the Daegu-Gyeongbuk region and nationwide. The government
advised people to wear masks, wash their hands, avoid crowds and meetings, work
remotely, and to join online religious services instead of going to churches.
Those with fevers or respiratory illnesses are urged to stay home and watch
their symptoms for 3 to 4 days. “People were shocked by the Shincheonji
cluster,” Chun says, which boosted compliance. Less than 1 month after Case 31
emerged, “The cluster is coming under control,” Oh says.
Yet
new clusters are emerging, and for 20% of confirmed cases, it’s unclear how
they became infected, suggesting there is still undetected community spread.
“As long as this uncertainty remains, we cannot say that the outbreak has
peaked,” Chun says.
More data needed
The
government hopes to control new clusters in the same way it confronted the one
in Shincheonji. The national testing capacity has reached a staggering 15,000
tests per day. There are 43 drive-through testing stations nationwide, a
concept now copied in the United States, Canada, and the United Kingdom. In the
first week of March, the Ministry of the Interior also rolled out a smartphone
app that can track the quarantined and collect data on symptoms.
Chun
says scientists are eager to see more epidemiological data. “We are literally
stamping our feet,” Chun says. KCDC releases the basic counts of patients,
their age and gender, and how many are linked to clusters. “That is not
enough,” Chun says. He and others would like to study detailed individual
patient data, which would enable epidemiologists to model the outbreak and
determine the number of new infections triggered by each case, also known as
the basic reproductive number or R0; the time from infection to the
onset of symptoms; and whether early diagnosis improved patients’ outcomes.
(South Korea has had 75 deaths so far, an unusually low mortality rate,
although the fact that Shincheonji church members are mostly young may have
contributed.) Chun says a group of epidemiologists and scientists has proposed
partnering with KCDC to gather and share such information, “and we are waiting
for their response.”
Kim
says medical doctors are also planning to share details of the clinical
features of COVID-19 cases in the country in forthcoming publications. “We hope
our experience will help other countries control this COVID-19 outbreak.”
With reporting by Ahn Mi-Young in Seoul.
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