Eastern Cereal and Oilseed Research Centre, Agriculture and Agri-Food Canada, 960 Carling Avenue, Ottawa, ON K1A 0C6, Canada.
Can J Microbiol. 2010 Sep;56(9):715-29. doi: 10.1139/w10-046.
Enterococci are gastrointestinal tract residents and also an important cause of nosocomial infections. To understand which species, virulence determinants, and antibiotic resistances are prevalent in enterococci shed by various hosts groups, a total of 1460 strains isolated from 144 fecal samples obtained from wastewater, domesticated mammals and birds, and wildlife were characterized. Identification of isolates to the species level showed that Enterococcus faecalis was dominant in domesticated mammals and birds and wildlife feces, whereas Enterococcus faecium was dominant among wastewater isolates, and that no single Enterococcus species could be associated with a specific host group. The frequency of 12 virulence determinants was evaluated among isolates, but no single virulence determinant could be associated with a specific host group. Resistance to 12 antibiotics was evaluated among isolates, and it was shown that the highest frequency of resistance at breakpoint concentration was found in domesticated mammals and birds (P ≤ 0.05 for 4 antibiotics). Our results suggests that (1) species identification and virulence typing of Enterococcus spp. isolates are not useful for the identification of the host groups responsible for fecal contamination of water by microbial source tracking and that (2) antibiotic use for clinical, veterinary, or animal husbandry practices is promoting resistance.
肠球菌是胃肠道的居民，也是医院感染的重要原因。为了了解哪些物种、毒力决定因素和抗生素耐药性在各种宿主群体排出的肠球菌中普遍存在，对从废水、驯化的哺乳动物和鸟类以及野生动物中获得的 144 份粪便样本中的 1460 株分离株进行了特征分析。分离株的种水平鉴定表明，粪肠球菌在驯化的哺乳动物和鸟类以及野生动物粪便中占优势，而屎肠球菌在废水中的分离株中占优势，没有单一的肠球菌物种可以与特定的宿主群体相关。评估了 12 种毒力决定因素在分离株中的频率，但没有单一的毒力决定因素可以与特定的宿主群体相关。评估了分离株对 12 种抗生素的耐药性，结果表明，在驯化的哺乳动物和鸟类中发现耐药性在断点浓度下的频率最高（4 种抗生素中 P ≤ 0.05）。我们的结果表明：（1）肠球菌属分离株的种鉴定和毒力分型对于通过微生物源追踪识别导致水粪便污染的宿主群体没有用处；（2）用于临床、兽医或畜牧业的抗生素使用正在促进耐药性的产生。
