A teenage pneumonia patient who died Wednesday morning in Daegu was coronavirus-negative, health officials said Thursday.

The Korea Centers for Disease Control and Prevention said in a briefing the 17-year-old’s death was not linked to COVID-19, the disease caused by the novel coronavirus.

Medics at the Daegu hospital had tested him for COVID-19 several times, as his chest imaging showed signs of a possible infection. The seven rounds of tests yielded mixed results, the hospital said.

The KCDC’s Vice Director Kwon Jun-wook told reporters the agency as well as two hospitals conducted postmortem virus tests on the patient’s samples, including blood, urine and liquid from the lower respiratory tract.

The virus was not detected in tests run by the three institutions. The earlier positive result appears to be due to a technical error or contamination at the lab, Kwon said.

The teen died after six days at Yeungnam University Hospital, five of which were spent in the intensive care unit. He was given treatment with an ECMO machine -- a life-support device used in cases of most severe respiratory failure -- from Saturday. He started having symptoms the evening of March 10 and was taken into the emergency room on Friday.

The hospital said he had no previous comorbidities or other health issues. His cause of death certificate attributes multiple organ failure.

The state clinical committee for emerging infectious diseases has concluded an autopsy was unnecessary, as the case was not a virus fatality.

By Kim Arin (arin@heraldcorp.com)