Dairy Cattle, a Potential Reservoir of Human Campylobacteriosis: Epidemiological and Molecular Characterization of Campylobacter jejuni From Cattle Farms

Abstract

Campylobacter jejuni is a major foodborne pathogen that is increasingly found worldwide and that is transmitted to humans through meat or dairy products. A detailed understanding of the prevalence and characteristics of C. jejuni in dairy cattle farms, which are likely to become sources of contamination, is imperative and is currently lacking. In this study, a total of 295 dairy cattle farm samples from 15 farms (24 visits) in Korea were collected. C. jejuni prevalence at the farm level was 60% (9/15) and at the animal level was 23.8% (68/266). Using the multivariable generalized estimating equation (GEE) model based on farm-environmental factors, we estimated that a high density of cattle and average environmental temperature (7 days prior to sampling) below 24°C affects the presence and survival of C. jejuni in the farm environment. Cattle isolates, together with C. jejuni from other sources (chicken and human), were genetically characterized based on analysis of 10 virulence and survival genes. A total of 19 virulence profile types were identified, with type 01 carrying eight genes (all except hcp and virB11) being the most prevalent. The prevalence of virB11 and hcp was significantly higher in isolates from cattle than in those from other sources (p < 0.05). Multilocus sequence typing (MLST) of C. jejuni isolates from three different sources mainly clustered in the CC-21 and CC-48. Within the CC-21 and CC-48 clusters, cattle isolates shared an indistinguishable pattern with human isolates according to pulsed-field gel electrophoresis (PFGE) and flaA-restriction fragment length polymorphism (RFLP) typing. This suggests that CC-21 and CC-48 C. jejuni from dairy cattle are genetically related to clinical campylobacteriosis isolates. In conclusion, the farm environment influences the presence and survival of C. jejuni, which may play an important role in cycles of cattle re-infection, and dairy cattle represent potential reservoirs of human campylobacteriosis. Thus, environmental management practices could be implemented on cattle farms to reduce the shedding of C. jejuni from cattle, subsequently reducing the potential risk of the spread of cattle-derived C. jejuni to humans through the food chain.

Molecular Characterization and Antibiotic Resistant Profiles of Campylobacter Species Isolated From Poultry and Diarrheal Patients in Southeastern China 2017–2019

“…Consistent with previous reports, the MLST data confirmed that Campylobacter is genetically diverse, with C. jejuni isolates being more diverse than C. coli (Kinana et al, 2007;Wang et al, 2011;Ngulukun et al, 2016). The dominant CCs in this study were CC-21 and CC-45 and were in agreement with prior findings from other countries in which CC-21 and CC-45 appear to be the largest complexes (Sheppard et al, 2010;Guyard-Nicodème et al, 2015;An et al, 2018). The prevalence of CC-353, CC-464, and CC-828 was lower than those in other regions of China (Zhang et al, 2017), supporting the idea that Campylobacter subtype diversity may differ by region and sampled area.…”

The Wild Mouse (Micromys minutus): Reservoir of a Novel Campylobacter jejuni Strain

“…derived from other sources. Because of the high genetic diversity of C. jejuni mentioned above, differences in the virulence/survival profiles of C. jejuni have been observed in most previous studies for the same host, and even in studies of livestock in the same farm (Young et al, 2007;An et al, 2018). However, the presence or absence of virulence/survival genes in all isolates from this study was similar, except for the virB11 gene.…”

“…Similarly, if a single C. jejuni isolate from wild mice captured in one sesame field did not harbor this gene, then no isolates from wild mice captured in that field harbored the gene (Table 2). VirB11, which is present on the pVir plasmid encoding a type-IV secretion system, is involved in horizontal gene transfer and is easily transferred between strains (Juhas et al, 2008); in the case of livestock, its distribution tendency has been found to be similar for the same farm (An et al, 2018). Therefore, the distribution of the virB11 gene in this study suggests that horizontal transmission of C. jejuni may occur frequently among M. minutus that share the same habitat.…”

“…Previous studies on livestock, including cattle, sheep, pigs, and poultry have indicated that, though the frequency of a specific sequence is often host-dependent, diverse genotypes of C. jejuni strains can be distributed among the same hosts and individuals (Colles et al, 2009;Ogden et al, 2009). For example, in cattle or poultry, various clones of C. jejuni may be present, even if the experiment was carried out on the same farm (Behringer et al, 2011;An et al, 2018). Despite the previously determined genetic diversity of C. jejuni, the absence of genetic heterogeneity among all isolates in this study suggests that C. jejuni from wild mice may have adapted to the gastrointestinal tract (GI) of M. minutus and that all isolates were genetically similar to each other, a result that has not been seen with other C. jejuni hosts.…”

“…Profiling Virulence/Survival Factors and Antibiotic-Resistance Patterns of Wild Mouse-Derived C. jejuni For all C. jejuni isolates, the presence and absence of virulence/survival-related genes were confirmed by PCR ( Table 1; Konkel et al, 1999;Datta et al, 2003;Müller et al, 2006;Bui et al, 2012;González-Hein et al, 2013;Harrison et al, 2014;Koolman et al, 2015;An et al, 2018). These genes corresponded to three secretion systems (flhB, virB11, and hcp), one adherence/colonization-related protein (cadF), two cell invasion-related proteins (pldA and iamA), one cytotoxinrelated protein (cdtB), and three survival-related factors (crsA, perR, and htrA).…”