1. Pulmonary and Critical Care Medicine (PCCM), Quanzhou First Hospital, Quanzhou, 362000 Fujian, China
2. Hospital Infection-Control Office, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, 362000 Fujian, China
3. Department of Nursing, Quanzhou First Hospital, Quanzhou, 362000 Fujian, China