Figure. Case map of confirmed coronavirus disease (COVID-19) cases associated with fitness dance classes in Cheonan, South Korea, by date of symptom onset and relationship. Instructors outside of Cheonan are excluded. In 7 cases, transmission was suspected in the presymptomatic phase and the longest period before symptom onset was 5 days. None of the instructors had COVID-19 symptoms on the day of the workshop, but instructors from Daegu, which recently had a large outbreak, developed symptoms 3 days after the workshop. Sports facilities are represented by bars on the left with the number of students per class included. Bold outlines indicate a positive test for COVID-19 in a person in the presymptomatic phase.