Scott Paul, Deye Gregory, Srinivasan Arjun, Murray Clinton, Moran Kimberly, Hulten Ed, Fishbain Joel, Craft David, Riddell Scott, Lindler Luther, Mancuso James, Milstrey Eric, Bautista Christian T, Patel Jean, Ewell Alessa, Hamilton Tacita, Gaddy Charla, Tenney Martin, Christopher George, Petersen Kyle, Endy Timothy, Petruccelli Bruno
Walter Reed Army Institute of Research, Silver Spring, MD 20850, USA.
Clin Infect Dis. 2007 Jun 15;44(12):1577-84. doi: 10.1086/518170. Epub 2007 May 8.
We investigated an outbreak of multidrug-resistant Acinetobacter baumannii-calcoaceticus complex infection among US service members injured in Iraq.
The investigation was conducted in Iraq and Kuwait, in the 2 military hospitals where the majority of injured service members were initially treated. After initially characterizing the outbreak, we evaluated 3 potential sources of infection for the period March 2003 to December 2004. The evaluation included screening samples that were obtained from the skin of patients for the presence of colonization and assessing the soil and health care environments for the presence of A. baumanii-calcoaceticus complex organisms. Isolates obtained from samples from patients in US Military treatment facilities, as well as environmental isolates, were genotypically characterized and compared using pulsed-field gel electrophoresis.
A. baumanii-calcoaceticus complex organisms were present on the skin in only 1 (0.6%) of 160 patients who were screened and in 1 (2%) of 49 soil samples. A. baumanii-calcoaceticus complex isolates were recovered from treatment areas in 7 of the 7 field hospitals sampled. Using pulsed-field gel electrophoresis, we identified 5 cluster groups in which isolates from patients were related to environmental isolates. One cluster included hospitalized patients who had not been deployed to Iraq. Among the clinical isolates, only imipenem, polymyxin B, and colistin demonstrated reliable in vitro antimicrobial activity. Generally, the environmental isolates were more drug susceptible than were the clinical isolates.
Our findings suggest that environmental contamination of field hospitals and infection transmission within health care facilities played a major role in this outbreak. On the basis of these findings, maintaining infection control throughout the military health care system is essential. Novel strategies may be required to prevent the transmission of pathogens in combat field hospitals.
我们调查了在伊拉克受伤的美国军人中发生的耐多药鲍曼不动杆菌-醋酸钙复合物感染疫情。
调查在伊拉克和科威特的2家军事医院进行，大多数受伤军人最初在这两家医院接受治疗。在初步确定疫情特征后，我们评估了2003年3月至2004年12月期间3种潜在感染源。评估包括筛查从患者皮肤获取的样本中是否存在定植，并评估土壤和医疗环境中是否存在鲍曼不动杆菌-醋酸钙复合物菌。从美国军事治疗机构患者样本以及环境样本中分离出的菌株，通过脉冲场凝胶电泳进行基因分型和比较。
在160名接受筛查的患者中，仅1名（0.6%）的皮肤存在鲍曼不动杆菌-醋酸钙复合物菌，49份土壤样本中1份（2%）存在该菌。在抽样的7家野战医院中，有7家的治疗区域分离出了鲍曼不动杆菌-醋酸钙复合物菌。通过脉冲场凝胶电泳，我们确定了5个聚类组，其中患者分离株与环境分离株相关。一个聚类组包括未被部署到伊拉克的住院患者。在临床分离株中，只有亚胺培南、多粘菌素B和黏菌素表现出可靠的体外抗菌活性。一般来说，环境分离株比临床分离株对药物更敏感。
我们的研究结果表明，野战医院的环境污染和医疗机构内的感染传播在此次疫情中起了主要作用。基于这些发现，在整个军事医疗系统中维持感染控制至关重要。可能需要新的策略来预防战地医院病原体的传播。
