According to HIGH UP Entertainment on March 11, STAYC member Yoon has tested positive for COVID-19. 

The agency revealed in a fan cafe update on this day, "During a preemptive self-diagnosis kit test conducted on March 10, Yoon saw positive results and underwent a PCR test immediately. As of March 11, Yoon has tested positive for COVID-19. Yoon has completed up to her third dose of the COVID-19 vaccine and is not experiencing any abnormal symptoms. She has begun treatment at home per health authorities' guidelines." 

The remaining STAYC members have all tested negative, but the group will put a temporary halt to all activities for the time being.