van Hoek Angela H A M, Stalenhoef Janneke E, van Duijkeren Engeline, Franz Eelco
National Institute for Public Health and the Environment (RIVM), PO Box 1, 3720 BA, Bilthoven, The Netherlands.
Department of Infectious Diseases, Leiden University Medical Center, PO Box 9600, 2300 RC, Leiden, The Netherlands.
Vet Microbiol. 2016 Oct 15;194:55-61. doi: 10.1016/j.vetmic.2016.04.008. Epub 2016 Apr 11.
During the last decade extended-spectrum cephalosporin (ESC)-resistant Escherichia coli from food-producing animals, especially from broilers, have become a major public health concern because of the potential transmission of these resistant bacteria or their plasmid-encoded resistance genes to humans. The objective of this study was to compare ESC-resistant E. coli isolates from broilers (n=149), humans in contact with these broilers (n=44), humans in the general population (n=63), and patients with a urinary tract infection (UTI) (n=10) with respect to virulence determinants, phylogenetic groups and extended-spectrum β-lactamase (ESBL)/plasmidic-AmpC (pAmpC) genes. The most prevalent ESBL/pAmpC genes among isolates from broilers and individuals on broiler farms were bla, bla and bla. In isolates from humans in the general population bla, bla and bla were found most frequently, whereas in UTI isolates bla predominated. The marker for enteroaggregative E. coli, aggR, was only identified in a broiler and human isolates from the general population. The extraintestinal virulence genes afa and hlyD were exclusively present in human isolates in the general population and UTI isolates. Multivariate analysis, based on ESBL/pAmpC resistance genes, virulence profiles and phylogenetic groups, revealed that most UTI isolates formed a clearly distinct group. Isolates from broilers and humans associated with broiler farms clustered together. In contrast, isolates from the general population showed some overlap with the former two groups but primarily formed a separate group. These results indicate than transmission occurs between broilers and humans on broiler farms, but also indicate that the role of broilers as a source of foodborne transmission of ESC-resistant E. coli to the general population and subsequently causative agents of human urinary tract infections is likely relatively small.
在过去十年中，产肉动物尤其是肉鸡中对超广谱头孢菌素（ESC）耐药的大肠杆菌，因其耐药菌或其质粒编码的耐药基因可能传播给人类，已成为一个主要的公共卫生问题。本研究的目的是比较来自肉鸡（n = 149）、接触这些肉鸡的人类（n = 44）、普通人群中的人类（n = 63）以及尿路感染（UTI）患者（n = 10）的ESC耐药大肠杆菌分离株在毒力决定因素、系统发育群和超广谱β-内酰胺酶（ESBL）/质粒介导的AmpC（pAmpC）基因方面的差异。肉鸡及肉鸡养殖场个体分离株中最常见的ESBL/pAmpC基因是bla、bla和bla。在普通人群的人类分离株中，最常发现的是bla、bla和bla，而在UTI分离株中bla占主导。肠聚集性大肠杆菌的标记aggR仅在一只肉鸡和普通人群的人类分离株中被鉴定出。肠外毒力基因afa和hlyD仅存在于普通人群的人类分离株和UTI分离株中。基于ESBL/pAmpC耐药基因、毒力谱和系统发育群的多变量分析表明，大多数UTI分离株形成了一个明显不同的组。来自肉鸡和与肉鸡养殖场相关的人类分离株聚集在一起。相比之下，普通人群的分离株与前两组有一些重叠，但主要形成一个单独的组。这些结果表明，肉鸡养殖场中肉鸡与人类之间存在传播，但也表明肉鸡作为ESC耐药大肠杆菌食源性传播给普通人群并随后成为人类尿路感染病原体来源的作用可能相对较小。
