People who test positive for the novel coronavirus after making a full recovery do not transmit the disease to others, health authorities said Monday, reversing earlier guidance directing for an additional two-week quarantine in such cases.

Jung Eun-kyeong, director general of the Korea Centers for Disease Control and Prevention, said health authorities arrived at this conclusion after examining 790 people who had come into contact with 285 patients who tested positive again post-recovery.

“There were three new virus cases among those who had come into contact with relapse patients. But we can’t rule out the possibility that they could have been exposed to the virus through a different route,” Jung said during a daily virus briefing.

It is difficult to conclude that the new patients contracted the virus from the relapse patients, because viruses from those patients and their contacts could not be grown in a laboratory, she added.

Some 100 relapsed patients had samples taken and the virus was isolated to be cultured, which returned negative results in every case, the KCDC revealed.

“We do not have a clear explanation for why the virus is detected in PCR tests. However, the virus was not detected in culture tests of samples that tested positive in PCR tests,” Han Myung-guk, an official in charge of virus analysis at the Korea Central Disaster and Safety Countermeasures Headquarters, said.

Based on the latest findings, relapse patients will not be required to self-quarantine for two weeks after being declared virus-free and can return to their daily lives without taking PCR tests, effective at 12:01 a.m. on Tuesday.

As of Friday, South Korea had 447 patients who had returned positive results for COVID-19 for a second time after having recovered, according to the KCDC.

This is roughly 4.5 percent of the 9,904 virus-free patients who have been released from isolation.

Jeong’s comments echoed Yoon Tae-ho, a senior Health Ministry official, who said there was no reason to believe that relapsed patients were contagious.

“After conducting epidemiological and virological surveys of relapse patients and those who have come into contact with them, we have not confirmed a reason backing that reinfected patients are infectious,” Yoon said at a daily morning briefing.

Korea’s daily count of new coronavirus cases stayed below 20 for the third day in a row on Monday, as the outbreak from Seoul’s party district of Itaewon seems to have been contained.

The accumulated number of infections here reached 11,065, up 15 from the previous day, as of Monday, according to the KCDC.

One patient succumbed to the virus, putting the death toll at 263.

Of the new cases, 10 were imported and five were from community transmission, with health authorities reiterating the need for vigilance as yet undetected cases could trigger community spread.

Five cases of community transmission were reported in Gyeonggi Province, North Chungcheong Province and Daegu, while Seoul reported no new cases.

The number of those released from isolation upon making full recoveries increased by 16 to 9,904, the KCDC said.

By Kim Bo-gyung (lisakim425@heraldcorp.com)