B씨는 집단감염이 발생한 11층이 아닌 9층 근무자로 다른 콜센터 직원의 접촉자인 것으로 확인됐다.
B is a worker on the 9th floor rather than the 11th floor where the group infection occurred, and it was confirmed that he/she was a contact person with another call center employee.