The 7-day quarantine for confirmed COVID-19 patients will be extended by 4 weeks until June 20th.
 
After 4 weeks, the government will re-evaluate the epidemic situation and decide whether to lift the quarantine obligation.

Lee Sang-min, the second deputy director of the Central Disaster and Safety Countermeasures Headquarters (Minister of Public Administration and Security), said in a remark on May 20th that the current epidemic can be managed sufficiently, but there are some concerns.
 
Deputy Director Lee explained, "New mutations with high contagious properties have been found in Korea, raising the possibility of reducing vaccine effectiveness and evading immunity."

Extracts translated from of the Gangwon Ilbo Newspaper. The original Korean article can be viewed here.