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South Korea has been held up as a paragon for containing the coronavirus, lauded by the world for flattening its curve, but it is now bracing for a possible second wave.

Two worlds have emerged in South Korea. In one, everyday life resembles something closer to normal: There are lines outside restaurants during lunchtime; streets are busier; some wear masks and some do not.

The other world, however, keeps its eye firmly on the slight daily uptick in the country's number of cases.

Despite methods like early testing and digital tracing, South Korea is bracing for a second wave of infection. The government recently pushed back the new school year. Despite efforts to protect children from being infected with the coronavirus, over 83 percent of South Korea's hagwons — cutthroat test prep centers for students — remain open.

Full coverage of the coronavirus outbreak

With many parts of the world wondering what a slow return to normal life will look like, South Korea's situation offers a warning: The curve doesn't necessarily stay flat.

Local and imported clusters

The first wave of the coronavirus struck South Korea in mid-February after a "superspreader" from the Shincheonji Church in Daegu, a major city southeast of Seoul, infected worshippers during a service — a single case that infected more than 6,000 people.

Since then, with the swift implementation of nonpharmaceutical initiatives, like refraining from handshakes and diligently wearing masks, South Korea significantly reduced its number of daily cases from a peak of 909 in late February to as low as 76 and 64 in mid-March.

Despite the general decline, 125 new cases were reported last Monday — a slight increase from the previous day, at 78. The new stats also showed a rising death toll.

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Local infection clusters have continued to set South Koreans on edge as case numbers fluctuate.

Most recently, a hospital in Daegu, the center of South Korea's outbreak, experienced another cluster infection, with at least 62 cases. Mannim Central Church in southwestern Seoul confirmed more positive tests, increasing its number to 33.

With the slight upticks, it's clear that South Korea hasn't fully contained the virus yet. But local clusters aren't the only problem.

South Korea is simultaneously coping with an influx of travelers from Europe and the U.S., which has resulted in more than 518 imported cases.

How widespread an infection cluster has to be to be considered another "wave" varies. Some local media refer to South Korea's first confirmed case on Jan. 20 involving a traveler from Wuhan to be the "first wave" and the Shincheonji outbreak to be the second.

Dr. Ki Moran, a professor at the National Cancer Center's Graduate School of Cancer Science and Policy, said that even the slightest loosening of social distancing fosters the danger of triggering another mass wave.

"A wave occurs when you see an increase followed by a decrease in the number of cases, not just once, but the pattern should repeat itself again, which in this case it has," Ki said. "Right now our greatest jeopardy is becoming complacent."

In efforts to push back against this doubled burden, every new arrival as of April 1 is placed in mandatory quarantine for 14 days, according to the Korea Centers for Disease Control and Prevention. Those who fail to comply with regulations may be imprisoned for up to a year or fined up to 10 million won, while foreigners risk facing deportation.

Reassessing the realities

How long can South Korea and the rest of the world live in isolation? In the United States alone, more than 6.5 million people filed for unemployment insurance in a week, highlighting the toll the virus has taken on those who cannot afford isolation.

Ki said South Korea is already planning ahead, brainstorming ways the country can practice "everyday distancing" that would introduce more sustainable lifestyle changes rather than temporary campaigns.

For instance, instead of having all children arrive and leave school at the same time, an alternative would be to conduct half of the coursework online and half in person to reduce the number of students in class. Rearranging lunch tables so students sit in a zigzag pattern rather that next to one another is also being considered.

A couple wear masks to protect against contracting the coronavirus in Seoul on Friday, April 3, 2020. Heo Ran / Reuters

But South Korea's decision to further move back the start of the school year points to the continual disruption that the coronavirus has inflicted.

"We can't just delay the entire educational system for a year," Ki said.

As of March 31, 9,786 total cases were confirmed in South Korea, moving the country down to 14th on the list of countries with COVID-19 cases.

"Hoping that a vaccine will be developed soon is too optimistic, " Ki said. "We have to acknowledge the reality of the situation we are in and make a plan."