https://m-en.yna.co.kr/view/AEN20200429007051320
As of Tuesday, a total of 277 people who recovered from COVID-19 have retested positive here, according to the Korea Centers for Disease Control and Prevention (KCDC).
The country's central clinical committee for emerging disease control said there was no live virus present in such cases, positively refuting theories like the virus being reactivated or reinfection.
They said that apparent reinfection cases came because fragments of the virus remained in their bodies and showed up in test kits.
Why do the South Koreans want my grandma to die?The country currently uses a reverse transcription polymerase chain reaction (PCR) test for the COVID-19 virus that works by finding the virus's genetic information, or RNA, in a sample taken from a patient.
The experts said this PCR test is so sensitive that it can still pick up parts of the small amount of RNA from a cell even after the person has recovered from COVID-19.
"RNA fragments still can exist in a cell even if the virus is inactivated," they said in a press release. "It is more likely that those who tested positive again picked up virus RNA that has already been inactivated."