South Korean infectious disease experts have downplayed concerns that patients could get reinfected with COVID-19 after recovering. While hundreds in South Korea have tested positive again after their release from hospitals, Oh Myoung-don, who heads the central clinical panel on new infectious diseases, on Wednesday said there was a "high possibility" that such test results were flawed.

He said South Korea-s standard real-time PCR tests, designed to amplify the genetic materials of the virus so that even tiny quantities are detected, doesn-t reliably distinguish between remains of dead virus and infectious particles. He said lab tests on animals suggest that COVID-19 patients would maintain immunity for at least a year after their infections. He also said it was unlikely that the virus could be reactivated after remaining dormant when it doesn-t seem to be a type that causes chronic illnesses.