以分子生物學探討萬古黴素抗藥性腸球菌群聚感染與環境污染之關係

Molecular Investigation of a Cluster of Vancomycin-Resistant Enterococcal Infections and its Correlation with Environmental Contamination

某醫學中心呼吸照護單位（respiratory care unit, RCU）於2010年8月份發現vancomycin-resistant Enterococcus faecium（VRE）感染人次為2人次，且發現一週內由RCU陸續轉出至一般病房有其他2位VRE新感染個案。為防止感染持續發生，我們進行人員再教育、落實接觸隔離措施、加強環境清消等感控措施，並對同室病人與環境進行VRE培養篩檢，共培養出39株VRE，其中22株為病人身上移生菌株，17株為環境菌株。脈衝式膠質電泳分析（pulsed-field gel electrophoresis, PFGE）及抗藥性基因鑑定，發現感染個案的PFGE型別為A型（1例）、B型（1例）與C型（2例），在病人間散佈的VRE以C型最多有10株，A型次之有4株，B型與D型各3株，E型與F型各1株，而環境間的散佈主要是B型（8株）、C型（6株）和A型（3株）。除3株PFGE D型菌株帶有vanB抗藥基因，其餘36株VRE皆帶vanA。經由感染管制措施的介入，之後追蹤3個月再無新個案發生。

In August 2011, 2 patients infected with vancomycin-resistant Enterococcus faecium (VRE) were identified in a respiratory care unit (RCU). Two new VRE-infected patients were identified in the general ward immediately after their transfer from the RCU in the following week. We investigated the outbreak in the RCU. We obtained 39 strains of VRE from the patients, their contacts, and the environment, which were analyzed by pulsed-field gel electrophoresis (PFGE). The PFGE results revealed 6 types of VRE. PFGE type-C spread was noted between patients. PFGE type-B and type-C spread was noted in the patients’ environment. After intervention with infection control measures, no VRE-infected patients were identified in the next 3 months.