Koga Vanessa L, Rodrigues Gabriela R, Scandorieiro Sara, Vespero Eliana C, Oba Alexandre, de Brito Benito G, de Brito Kelly C T, Nakazato Gerson, Kobayashi Renata K T
1 Departamento de Microbiologia, Centro de Ciências Biológicas, Campus Universitário, Universidade Estadual de Londrina , Paraná, Brasil .
2 Departamento de Patologia e Análises Clínicas e Toxicológicas, Centro de Ciências da Saúde, Hospital Universitário, Universidade Estadual de Londrina , Paraná, Brasil .
Foodborne Pathog Dis. 2015 Jun;12(6):479-85. doi: 10.1089/fpd.2014.1888. Epub 2015 May 14.
The frequent use of antimicrobials in commercial poultry production has raised concerns regarding the potential impact of antimicrobials on human health due to selection for resistant bacteria. Several studies have reported similarities between extraintestinal pathogenic Escherichia coli (ExPEC) strains isolated from birds and humans, indicating that these contaminant bacteria in poultry may be linked to human disease. The aim of our study was to analyze the frequency of antimicrobial resistance and virulence factors among E. coli strains isolated from commercial chicken carcasses in Paraná, Brazil, in 2007 and 2013. A total of 84 E. coli strains were isolated from chicken carcasses in 2007, and 121 E. coli strains were isolated in 2013. Polymerase chain reaction was used to detect virulence genes (hlyF, iss, ompT, iron, and iutA) and to determine phylogenetic classification. Antimicrobial susceptibility testing was performed using 15 antimicrobials. The strains were also confirmed as extended-spectrum β-lactamase (ESBL)-producing E. coli with phenotypic and genotypic tests. The results indicated that our strains harbored virulence genes characteristic of ExPEC, with the iutA gene being the most prevalent. The phylogenetic groups D and B1 were the most prevalent among the strains isolated in 2007 and 2013, respectively. There was an increase in the frequency of resistance to a majority of antimicrobials tested. An important finding in this study was the large number of ESBL-producing E. coli strains isolated from chicken carcasses in 2013, primarily for the group 2 cefotaximase (CTX-M) enzyme. ESBL production confers broad-spectrum resistance and is a health risk because ESBL genes are transferable from food-producing animals to humans via poultry meat. These findings suggest that our strains harbored virulence and resistance genes, which are often associated with plasmids that can facilitate their transmission between bacteria derived from different hosts, suggesting zoonotic risks.
在商业家禽生产中频繁使用抗菌药物引发了人们对其因选择耐药细菌而对人类健康产生潜在影响的担忧。多项研究报告了从禽类和人类中分离出的肠外致病性大肠杆菌（ExPEC）菌株之间的相似性，这表明家禽中的这些污染细菌可能与人类疾病有关。我们研究的目的是分析2007年和2013年从巴西巴拉那州商业鸡肉 carcasses 中分离出的大肠杆菌菌株的抗菌药物耐药性频率和毒力因子。2007年共从鸡肉 carcasses 中分离出84株大肠杆菌菌株，2013年分离出121株大肠杆菌菌株。采用聚合酶链反应检测毒力基因（hlyF、iss、ompT、铁和iutA）并确定系统发育分类。使用15种抗菌药物进行抗菌药物敏感性测试。还通过表型和基因型测试确认这些菌株为产超广谱β-内酰胺酶（ESBL）的大肠杆菌。结果表明，我们的菌株携带ExPEC特有的毒力基因，其中iutA基因最为普遍。系统发育组D和B1分别是2007年和2013年分离出的菌株中最普遍的。对大多数测试抗菌药物的耐药频率有所增加。本研究的一个重要发现是2013年从鸡肉 carcasses 中分离出大量产ESBL的大肠杆菌菌株，主要是针对2组头孢他美酯酶（CTX-M）酶。产ESBL赋予广谱耐药性，并且是一种健康风险，因为ESBL基因可通过禽肉从产食动物传播给人类。这些发现表明，我们的菌株携带毒力和耐药基因，这些基因通常与质粒相关，质粒可促进它们在源自不同宿主的细菌之间传播，提示存在人畜共患病风险。
