At first, the 47-year-old restaurant owner thought he was just tired from work. Doctors prescribed some cold medicine. But his headache worsened. He started to run a fever.
"I still didn't think I had contracted the coronavirus," Kim Seung-hwan recalled. "I only saw that on the news about China, and I have not traveled outside South Korea recently."
It was in mid-February, before clusters of coronavirus infection were reported around his hometown, Yeongcheon, about 180 miles southeast of Seoul. But the region would quickly become the center of the country's outbreak.
Kim's condition did not improve, and he went to a bigger hospital in nearby Daegu city on Feb. 18. At that point, coronavirus cases were starting to appear nearby. Just hours before Kim arrived at the hospital, the first coronavirus case was confirmed in Daegu.
Nurses in protective gear whisked Kim away to an isolation ward.
Kim's account - of infection, fear and recovery - is just one story among tens of thousands as the coronavirus spreads around the world. But it offers a window into the arc of the disease for some patients and the toll it exacts on the body and mind.
Kim was well aware that the virus had claimed lives, including some like him: the relatively young and healthy. As he grew sicker, the thoughts began to creep in: Would the covid-19 disease take him as well?
"Fears grew as I was left in the dark about what the virus could do to my body," he told The Washington Post in a telephone interview. "I could not but wonder if it could threaten my life."
His first moments in the hospital were a blur of activity.
Because he displayed pneumonia-like symptoms, he was quarantined in a negative-pressure room that keeps the air from seeping outside. Doctors took swabs from his nose and mouth to test for covid-19.
Kim waited for the results in the isolation ward. "The only thing I could hear was the buzzing noise of the ventilator," Kim said. He was not sure if his headache was a symptom of the virus or from snowballing concerns about possible infection in his family home and his restaurant.
Kim and a dozen other patients in Daegu and the surrounding North Gyeongsang province tested positive, among the first cases confirmed in South Korea.
Now, the number of coronavirus cases in South Korea has reached more than 4,200. Nearly 90 per cent are in Daegu and North Gyeongsang.
Kim watched cable news in the hospital ward as reports of coronavirus grew in South Korea and beyond. The TV and his phone were his links to the outside world. All visitors were banned.
As he saw the news of the virus spreading in his town, Kim's thoughts were with his wife and daughter, who had taken care of him at home. He remembered their worried eyes on him tossing and turning in his bed from severe pain.
He couldn't sleep for several nights in a row. "I was so tired, but could not fall asleep because of the aches and pain felt all over my body," he said.
It was an unpleasant kind of heat - different from the feeling after a sweaty game of badminton. The fever induced by the coronavirus felt "achingly hot," Kim said. His body temperature spiked above 100 degrees.
Doctors at the hospital prescribed him antibiotics, other medicine and intravenous fluids.
He was sent spare underwear and towels from home, which he lacked because he was hospitalized so abruptly. His family also sent him fried kimchi and other home-cooked dishes.
Four days into treatment, on Feb. 21, the doctors said his lungs had returned to normal. his symptoms started to ease. His fever broke. His head stopped aching.
But the worries still raged. The television he watched to distract himself from the pain beamed alerts of South Korea's first death from the coronavirus.
Would it cripple his body? Had he infected his family and the customers at his restaurant?
Immediately after Kim's diagnosis, the provincial government tracked down and published the list of the places he had visited during the four days since he started displaying symptoms. Health authorities in South Korea take those measures with every patient to help the public identify the risks.
The clinics Kim visited and his seafood restaurant were listed online and shut down for disinfection. His family and customers at his restaurant have been tested for the virus. No relatives have turned up positive. Neither has anyone who visited the restaurant, he says, as far as he knows.
Kim's health turned a corner last week. He could walk around inside the ward and started doing light exercises.
He tested negative for the virus on Feb. 24 and again the next day. On Wednesday, eight days after he was diagnosed, he was released from the hospital.
"I was so relieved," he said, "so happy to be back surrounded by my family."
Kim is now on a self-imposed 14-day quarantine, staying in his room and not dining with his wife and daughter. "The doctors told me I can go back to my daily life, but the fear of reinfection still lingers in my mind," he said.