Mohamed Muhanad, Owens Kris, Gajewski Abby, Clabots Connie, Johnston Brian, Thuras Paul, Kuskowski Michael A, Johnson James R
University of Minnesota, Minneapolis, Minnesota, USA
Veterans Affairs Medical Center (VAMC), Minneapolis, Minnesota, USA Ecolab, St. Paul, Minnesota, USA.
Appl Environ Microbiol. 2015 Jul;81(13):4498-506. doi: 10.1128/AEM.00638-15. Epub 2015 Apr 24.
How extraintestinal pathogenic Escherichia coli (ExPEC) and antimicrobial-resistant E. coli disseminate through the population is undefined. We studied public restrooms for contamination with E. coli and ExPEC in relation to source and extensively characterized the E. coli isolates. For this, we cultured 1,120 environmental samples from 56 public restrooms in 33 establishments (obtained from 10 cities in the greater Minneapolis-St. Paul, MN, metropolitan area in 2003) for E. coli and compared ecological data with culture results. Isolates underwent virulence genotyping, phylotyping, clonal typing, pulsed-field gel electrophoresis (PFGE), and disk diffusion antimicrobial susceptibility testing. Overall, 168 samples (15% from 89% of restrooms) fluoresced, indicating presumptive E. coli: 25 samples (2.2% from 32% of restrooms) yielded E. coli isolates, and 10 samples (0.9% from 16% of restrooms) contained ExPEC. Restroom category and cleanliness level significantly predicted only fluorescence, gender predicted fluorescence and E. coli, and feces-like material and toilet-associated sites predicted all three endpoints. Of the 25 E. coli isolates, 7 (28%) were from phylogenetic group B2(virulence-associated), and 8 (32%) were ExPEC. ExPEC isolates more commonly represented group B2 (50% versus 18%) and had significantly higher virulence gene scores than non-ExPEC isolates. Six isolates (24%) exhibited ≥3-class antibiotic resistance, 10 (40%) represented classic human-associated sequence types, and one closely resembled reference human clinical isolates by pulsed-field gel electrophoresis. Thus, E. coli, ExPEC, and antimicrobial-resistant E. coli sporadically contaminate public restrooms, in ways corresponding with restroom characteristics and within-restroom sites. Such restroom-source E. coli strains likely reflect human fecal contamination, may pose a health threat, and may contribute to population-wide dissemination of such strains.
肠外致病性大肠杆菌（ExPEC）和耐抗菌药物的大肠杆菌如何在人群中传播尚不清楚。我们研究了公共卫生间中大肠杆菌和ExPEC的污染情况与来源的关系，并对大肠杆菌分离株进行了广泛的特征分析。为此，我们从明尼苏达州明尼阿波利斯-圣保罗市大都市区10个城市的33个场所的56个公共卫生间采集了1120份环境样本（于2003年获得），用于培养大肠杆菌，并将生态数据与培养结果进行比较。对分离株进行了毒力基因分型、系统发育分型、克隆分型、脉冲场凝胶电泳（PFGE）和纸片扩散法抗菌药敏试验。总体而言，168份样本（来自89%的卫生间，占15%）发出荧光，表明可能存在大肠杆菌：25份样本（来自32%的卫生间，占2.2%）培养出大肠杆菌分离株，10份样本（来自16%的卫生间，占0.9%）含有ExPEC。卫生间类别和清洁程度仅显著预测荧光，性别预测荧光和大肠杆菌，而类粪便物质和与马桶相关的部位预测所有三个终点。在25株大肠杆菌分离株中，7株（28%）来自系统发育B2组（与毒力相关），8株（32%）为ExPEC。ExPEC分离株更常见于B2组（50%对18%），且毒力基因评分显著高于非ExPEC分离株。6株分离株（24%）表现出≥3类抗生素耐药性，10株（40%）代表典型的与人类相关的序列类型，1株通过脉冲场凝胶电泳与参考人类临床分离株极为相似。因此，大肠杆菌、ExPEC和耐抗菌药物的大肠杆菌偶尔会污染公共卫生间，其方式与卫生间特征和卫生间内场所相对应。这种来自卫生间源的大肠杆菌菌株可能反映了人类粪便污染，可能构成健康威胁，并可能导致此类菌株在人群中的传播。
