Division of Environmental Epidemiology, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.
Department of Bacteriology and Epidemiology, Wageningen Bioveterinary Research, Lelystad, The Netherlands.
Microbiol Spectr. 2023 Feb 14;11(1):e0294722. doi: 10.1128/spectrum.02947-22. Epub 2023 Jan 17.
Extended-spectrum beta-lactamase (ESBL)-producing have been increasingly isolated from pigs, highlighting their potential for transmission to humans living and/or working within pig farms. As longitudinal data on the prevalence and the molecular characteristics of such isolates from the high-risk farming population remain scarce, we performed a long-term study on 39 Dutch pig farms. Fecal samples from pigs, farmers, family members, and employees were collected during four sampling occasions with a 6-month period. The presence of ESBL-producing and their molecular characteristics (ESBL gene, plasmid, and sequence types) were determined by standard methods. Data on personal and farm characteristics were collected using questionnaires. ESBL-producing Escherichia coli was present in pigs at least once for 18 of 39 farms and in 17 of 146 farmers, family members, and/or employees. Among these 417 E. coli isolates, was the most frequently observed ESBL gene in pigs ( = 261) and humans ( = 25). Despite the great variety in plasmid (sub)types and E. coli sequence types (STs), we observed genetic similarity between human- and pig-derived isolates in (i) ESBL gene, plasmid (sub)type, and ST, suggesting potential clonal transmission in seven farms, and (ii) only ESBL gene and plasmid (sub)type, highlighting the possibility of horizontal transfer in four farms. Five pig farmers carried ESBL producers repeatedly, of whom two carried an identical combination of gene, plasmid (sub)type, and ST over time. Human ESBL carriage was associated with both presence of ESBL producers in pigs and average number of hours working on the pig farm per week, while prolonged human carriage was observed only incidentally. Extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli represents a public health hazard due to reduced therapeutic options for the treatment of infections. Although direct contact with pigs is considered a risk factor for human ESBL-producing E. coli carriage through occupational exposure, nationwide data regarding the occurrence of such isolates among pigs and humans living and/or working on farms remain scarce. Therefore, we determined (i) the longitudinal dynamics in prevalence and molecular characteristics of ESBL-producing E. coli in Dutch pig farmers and their pigs over time and (ii) the potential transmission events between these reservoirs based on genetic relatedness and epidemiological associations in longitudinal data. Our data suggesting the possibility of clonal and horizontal dissemination of ESBL-producing Escherichia coli between pigs and pig farmers can be used to inform targeted intervention strategies to decrease the within-farm human exposure to ESBL-producing E. coli.
产超广谱β-内酰胺酶（ESBL）的 在猪中的分离日益增多，这突显了它们向生活在或工作在养猪场的人类传播的潜力。由于有关高风险养殖人群中此类分离株的流行率和分子特征的纵向数据仍然很少，因此我们对 39 个荷兰养猪场进行了长期研究。在四个 6 个月的采样期间，从猪、农民、家庭成员和员工中采集粪便样本。通过标准方法确定产 ESBL 的 及其分子特征（ESBL 基因、质粒和序列类型）。使用问卷收集个人和农场特征的数据。39 个农场中有 18 个至少在一次采样中发现猪中存在产 ESBL 的 ，17 个农场中发现 146 个农民、家庭成员和/或员工中存在产 ESBL 的 。在这 417 株 E. coli 分离株中， 是猪中最常见的 ESBL 基因（=261）和人类（=25）。尽管质粒（亚）型和 E. coli 序列类型（ST）存在很大差异，但我们在（i）ESBL 基因、质粒（亚）型和 ST 之间观察到人类和猪源分离株之间的遗传相似性，这表明在七个农场中存在潜在的克隆传播，和（ii）仅 ESBL 基因和质粒（亚）型，突出了在四个农场中存在水平转移的可能性。五名猪农反复携带 ESBL 生产者，其中两名在时间推移中携带相同的基因、质粒（亚）型和 ST 组合。人类携带 ESBL 与猪中存在 ESBL 生产者和每周在养猪场工作的平均小时数有关，而长时间携带仅偶尔观察到。 产超广谱β-内酰胺酶（ESBL）的大肠杆菌由于治疗感染的治疗选择减少，对公共卫生构成威胁。尽管直接接触猪被认为是通过职业暴露导致人类携带产 ESBL 的大肠杆菌的危险因素，但有关在农场中生活和/或工作的猪和人类中此类分离株发生的全国数据仍然很少。因此，我们确定了（i）荷兰猪农及其猪中 ESBL 生产的大肠杆菌的纵向动态在时间上的流行率和分子特征，以及（ii）基于纵向数据中的遗传相关性和流行病学关联，这些储层之间的潜在传播事件。我们的数据表明，猪和猪农之间产 ESBL 的大肠杆菌可能存在克隆和水平传播，这可以用于为减少猪场内人类接触产 ESBL 的大肠杆菌提供信息，从而制定有针对性的干预策略。
