피험자는 관찰 기간 동안 방문 목적으로 병원에 입원한 사람과 환자와 직접 접촉하거나 환자 주변 환경과 접촉한 사람으로 선정되었다.
The subjects were selected as those who came to the hospital for the purpose of a visit during the observation period and who were in direct contact with the patient or in contact with the patient's surrounding environment.