弯曲杆菌是工业化国家细菌性肠胃炎的主要原因,以家禽水库为主要传染源。然而,最近一项关于来源归因的研究表明,牛可能是法国人类污染的来源(Thépault等人。,2017)。然而,关于法国牛的嗜热弯曲杆菌流行病学的数据很少。这项研究的目的是收集这些动物中嗜热弯曲杆菌流行的新数据,并对空肠弯曲杆菌亚型进行分离,以评估牛在弯曲杆菌病中的潜在意义。在欧洲最大的牛屠宰场之一进行了为期6个月的调查。根据统计代表性抽样计划,收集959例肠内容物样品(483只成年牛和476只小牛)。ISO10272标准和Maldi-Tof的改编版本用于检测和形成嗜热弯曲杆菌分离株。在收集的2000多个嗜热弯曲杆菌分离物中,用比较基因组指纹(CGF40)对649株空肠杆菌分离株进行分型,并使用多位点序列分型(MLST)对77株分离株的子集进行分型.同时,对法国发生的临床分离株进行基因分型.在屠宰场水平,全球牛群中嗜热弯曲杆菌的患病率为69.1%(CI95%=66.1,72.1)。在成年牛身上,患病率为39.3%,99.4%的小牛受到污染,空肠弯曲杆菌是最普遍的物种,患病率分别为37.3%和98.5%,分别和成年牛遗传多样性较高。大肠杆菌的患病率较低,成年牛的患病率为3%,小牛的患病率为12.5%。MLST和CGF40基因分型在牛分离株中没有显示大量的簇,但很少的簇占人口的很大一部分(CC-21,CC-61,CC-48和CC-257)。通过与临床基因型的比较,牛的遗传多样性明显较低。此外,在来自两个起源的基因型之间观察到显著的重叠,人类分离物中存在4个主要牛群中的3个。这项研究为法国牛生产中嗜热弯曲杆菌和空肠弯曲杆菌的流行病学及其对人类感染的潜在影响提供了新的见解。
Campylobacter is the leading cause of bacterial gastroenteritis in industrialized countries, with poultry reservoir as the main source of infection. Nevertheless, a recent study on source attribution showed that cattle could be a source of human contamination in France (Thépault et al., 2017). However, few data are available on thermophilic Campylobacter epidemiology in cattle in France. The aim of this study is to collect new data of thermophilic Campylobacter prevalence in these animals and to subtype C. jejuni isolates to assess the potential implication of cattle in campylobacteriosis. A 6-month survey was carried out in one of the largest European slaughterhouse of cattle. Based on a statistical representative sampling plan, 959 intestinal content samples (483 adult cattle and 476 calves) were collected. An adapted version of the ISO 10272 standard and Maldi-Tof were used for detection and speciation of thermophilic Campylobacter isolates. Within more than 2000 thermophilic Campylobacter isolates collected, a selection of 649 C. jejuni isolates was typed with Comparative Genomic Fingerprinting (
CGF40) and a subset of 77 isolates was typed using Multilocus Sequence Typing (MLST). Simultaneously, clinical isolates occurred in France were genotyped. Prevalence of thermophilic Campylobacter in the global cattle population was 69.1% (CI95% = 66.1, 72.1) at slaughterhouse level. In adult cattle, the prevalence was 39.3%, while 99.4% of calves were contaminated, and C. jejuni was the most prevalent species with prevalence of 37.3 and 98.5%, respectively and a higher genetic diversity in adult cattle. The prevalence of C. coli was lower with 3% in adult cattle and 12.5% in calves. MLST and
CGF40 genotyping did not showed a high number of clusters within cattle isolates but the predominance of few clusters accounted for a large part of the population (CC-21, CC-61, CC-48, and CC-257). By comparison with clinical genotypes, genetic diversity was significantly lower in cattle. Moreover, significant overlap was observed between genotypes from both origins, with 3 of the 4 main cattle clusters present in human isolates. This study provides new insights on the epidemiology of thermophilic Campylobacter and C. jejuni in cattle production in France and their potential implication in human infection.