On December 13, Yu Jae Seok's management agency Antenna broke news regarding Yu Jae Seok.
The agency stated, "Yu Jae Seok was fully vaccinated by the end of September. But he has been close to someone who has been tested positive for COVID-19 on December 11. He got tested on that day, and the result was negative at that time."
They continued, "Then, he took another test this morning, where he tested positive for COVID-19. All his schedule was immediately canceled. He will follow the guidelines by the Disease Control and Prevention."
The production team said, "We were scheduled for a shoot today, but Yu Jae Seok didn't take part in the shooting. Our staff and 'Running Man' members had no recent contact with Yu Jae Seok."
They resumed, "However, just to make sure that we were all free from the virus on site, everyone got tested before the shooting. We only allowed people with negative results to enter the site."