Department of Pathogen Molecular Biology, London School of Hygiene & Tropical Medicine, Hinxton.
Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton.
Clin Infect Dis. 2020 Jan 2;70(2):219-226. doi: 10.1093/cid/ciz174.
Klebsiella pneumoniae is a human, animal, and environmental commensal and a leading cause of nosocomial infections, which are often caused by multiresistant strains. We evaluate putative sources of K. pneumoniae that are carried by and infect hospital patients.
We conducted a 6-month survey on 2 hematology wards at Addenbrooke's Hospital, Cambridge, United Kingdom, in 2015 to isolate K. pneumoniae from stool, blood, and the environment. We conducted cross-sectional surveys of K. pneumoniae from 29 livestock farms, 97 meat products, the hospital sewer, and 20 municipal wastewater treatment plants in the East of England between 2014 and 2015. Isolates were sequenced and their genomes compared.
Klebsiella pneumoniae was isolated from stool of 17/149 (11%) patients and 18/922 swabs of their environment, together with 1 bloodstream infection during the study and 4 others over a 24-month period. Each patient carried 1 or more lineages that was unique to them, but 2 broad environmental contamination events and patient-environment transmission were identified. Klebsiella pneumoniae was isolated from cattle, poultry, hospital sewage, and 12/20 wastewater treatment plants. There was low genetic relatedness between isolates from patients/their hospital environment vs isolates from elsewhere. Identical genes encoding cephalosporin resistance were carried by isolates from humans/environment and elsewhere but were carried on different plasmids.
We identified no patient-to-patient transmission and no evidence for livestock as a source of K. pneumoniae infecting humans. However, our findings reaffirm the importance of the hospital environment as a source of K. pneumoniae associated with serious human infection.
肺炎克雷伯菌是一种人类、动物和环境共生菌，也是医院感染的主要原因，这些感染通常是由多耐药菌株引起的。我们评估了携带并感染医院患者的肺炎克雷伯菌的可能来源。
我们在 2015 年对英国剑桥阿登布鲁克医院的 2 个血液病房进行了为期 6 个月的调查，以从粪便、血液和环境中分离肺炎克雷伯菌。我们在 2014 年至 2015 年期间对英格兰东部的 29 个养殖场、97 个肉类产品、医院污水和 20 个城市污水处理厂的肺炎克雷伯菌进行了横断面调查。对分离株进行测序并比较其基因组。
在研究期间，从 149 名患者中的 17 名（11%）和 922 名患者环境样本中的 18 名患者中分离出肺炎克雷伯菌，同时有 1 例血流感染和 4 例其他患者在 24 个月内发生。每位患者携带 1 种或多种独特的谱系，但发现了 2 次广泛的环境污染事件和患者-环境传播。从牛、家禽、医院污水和 20 个污水处理厂中的 12 个中分离出肺炎克雷伯菌。患者/其医院环境与其他地方的分离株之间遗传相关性较低。从人类/环境和其他地方分离的肺炎克雷伯菌都携带编码头孢菌素耐药性的相同基因，但这些基因位于不同的质粒上。
我们没有发现患者之间的传播，也没有证据表明牲畜是感染人类的肺炎克雷伯菌的来源。然而，我们的研究结果再次证实了医院环境作为与严重人类感染相关的肺炎克雷伯菌来源的重要性。
