A teenager in Daegu, South Korea, tested negative for the new strain of coronavirus but later tested positive in DNA tests. He died Wednesday. Photo by Thomas Maresca/UPI | License Photo

March 17 (UPI) -- A South Korean teen died due to "sudden pneumonia" after testing negative for the new strain of coronavirus multiple times, local authorities said Wednesday.

The case is baffling medical experts. The 17-year-old boy, a resident of the South Korean city of Daegu, had tested negative for the coronavirus eight times, local television network SBS reported.


Jeong Eun-kyeong, director of the Korea Centers for Disease Control and Prevention, said at a regular press briefing the patient had undergone tests several times.

"Even after all test results came back negative, due to other DNA tests where the results were positive [for the coronavirus], at this point we are assessing the case as 'undetermined," Jeong told reporters.

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The patient who died Wednesday was a high school student in Daegu. He began experiencing a headache on the evening of March 10, then developed a fever on Wednesday.

Two days later, the patient visited Gyeongsang Joongang Hospital, where he received a negative test result for the virus. The next day, a chest X-ray showed severe inflammation of both lungs.

His symptoms rapidly deteriorated Friday, and he was placed on life support. But even after treatment using an artificial lung, or oxygenator, he did not recover, according to reports.

South Korea is moving toward greater restrictions that target businesses where crowding may occur, according to Yonhap on Wednesday.

Lee Jae-myung, the governor of Gyeonggi Province, said facilities including Internet cafes, karaoke bars, clubs and other "multipurpose spaces," will be subject to new rules.

The policy requires the businesses to keep a list of incoming customers, use masks at all times and bar people showing symptoms of COVID-19. Failure to comply will result in a fine of about $2,400.

South Korea is reporting a rising number of patients who were confirmed for the disease following trips to Europe. On Tuesday and Wednesday alone, eight COVID-19 patients who recently returned from Europe were confirmed in the Seoul area, according to Yonhap.