Detection of Arcobacter butzleri and Arcobacter cryaerophilus in Clinical Samples of Humans and Foods of Animal Origin by Cultural and Multiplex PCR Based Methods

Arcobacter species in milk contamination: a prevalence-based systematic review and meta-analysis

AIMS

Milk is consumed raw or minimally processed and plays a role in the dissemination of pathogens of public health concerns. The present investigation is aimed at assessing the occurrence of pathogenic Arcobacter species in 2945 milk samples.

METHODS AND RESULTS

Arcobacter data systematically retrieved from five repositories until 20 February 2022 according to PRISMA principles were logit transformed and fitted using a generalized linear mixed-effects model. The between-study heterogeneity was estimated as I2-value. Leave-one-out cross-validation and funnel plot with Egger's tests were used to assess the hardiness and bias in the model. The global prevalence of Arcobacter genus in the milk was 12% [95% confidence interval (CI): 7-19%; I2 = 87.3%, 95% CI: 83.0-90.6%] and no publication bias observed (Egger's test: P = 0.112). Arcobacter genus prevalence in milk was 13% (95% CI: 5-30%), 10% (95% CI: 1-46%), and 9% (95% CI: 4-19%) in Europe, South America, and Asia, respectively. Arcobacter butzleri was the most prevalent [8% (95% CI: 4-13%)], followed by A. cryaerophilus [0.6% (95% CI: 0.2-33.2%)] and A. skirrowii [0.19% (95% CI: 0.03-1.2%)]. Also, species-specific prevalence of A. butzleri, A. cryaerophilus, and A. skirrowii varied continentally, but the test for species-specific/continental differences was not significantly different (P > 0.5).

Prevalence and antibacterial susceptibilities of Arcobacter spp. and Campylobacter spp. from fresh vegetables

This study was aimed at the isolation and identification of Arcobacter spp. and Campylobacter spp. from fresh vegetables sold at district markets in the Kayseri province, and at the determination of the antibacterial susceptibility of the recovered isolates. For this purpose, a total of 175 vegetable samples, including 35 spinach, 35 lettuce, 35 parsley, 35 arugula, and 35 radish samples, were collected. While the pre-enrichment and membrane filtration techniques were used for the isolation of Arcobacter spp., the pre-enrichment and direct inoculation methods were used for the isolation of Campylobacter spp. The isolates were identified by means of phenotypic tests and the polymerase chain reaction (PCR), using genus- and species-specific primers. In addition, the susceptibilities of the isolates to amoxicillin-clavulanic acid, enrofloxacin, erythromycin, gentamicin, neomycin, streptomycin, and tetracycline were determined by the disk diffusion method. Out of the 175 vegetable samples tested, 93 (53.14%) were found to be positive for Arcobacter spp., and 119 Arcobacter spp. isolates were recovered from these 93 positive samples. All of the samples examined were found to be negative for Campylobacter spp. One hundred one (86%) and 14 (10%) of the 119 Arcobacter isolates obtained were identified as A. butzleri and A. cryaerophilus, respectively, but four isolates could not be identified at the species level by mPCR. Mixed contamination with more than one species and/or genotypes of Arcobacter was detected in 24 of the positive samples. While all of the Arcobacter isolates were susceptible to erythromycin, gentamicin, streptomycin, and tetracycline, 2 (1.68%), 2 (1.68%), and 5 (4.20%) isolates were resistant to amoxicillin/clavulanic acid, enrofloxacin, and neomycin, respectively. Consequently, the determination of a high prevalence of arcobacters and mixed contamination with more than one species and/or genotypes of arcobacters in vegetables often consumed raw by humans demonstrated that the consumption of raw vegetables may be a risk to the public health.

Occurrence and Antibiotic Resistance of Arcobacter Species Isolates from Poultry in Tunisia

ABSTRACT

Arcobacter is considered an emergent foodborne enteropathogen. Despite the high prevalence of this genus in poultry, the occurrence of Arcobacter spp. contamination in Tunisia remains unclear. The objectives of this study were (i) to isolate Arcobacter species (A. butzleri and A. cryaerophilus) by the culture method from different species of raw poultry meat, (ii) to verify the isolates by multiplex PCR (m-PCR) assay and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), and (iii) to determine the antibiotic resistance profiles of the isolates. A total of 250 poultry product samples (149 chicken and 101 turkey) were collected from various supermarkets in Sfax. The samples consisted of breasts, wings, legs, and neck skins. The overall isolation frequency of Arcobacter spp. was 10.4%. Arcobacter spp. were found in 13.42% of the chicken samples and in 5.49% of the turkey samples. All the acquired isolates were subject to detailed confirmation with subsequent species classification using m-PCR and MALDI-TOF MS. A. butzleri was found in 22 samples (84.61%) and A. cryaerophilus in 4 samples (15.38%). Thus, m-PCR and MALDI-TOF MS were able to detect A. butzleri significantly better than the conventional method (χ2 = 49.1 and P < 0.001). Arcobacter was isolated from poultry in every season, at contamination levels of 30.76, 23.07, 19.23, and 26.92% in summer, spring, autumn, and winter, respectively. The disk diffusion method was used to determine the susceptibility of Arcobacter isolates to six antimicrobial drugs. All A. butzleri isolates (n = 24) were significantly resistant to erythromycin (P = 0.0015), ampicillin (P = 0.001), and ciprofloxacin (P = 0.05). All tested A. cryaerophilus strains (n = 4) were susceptible to ampicillin, gentamicin, and amoxicillin-clavulanic acid. Multidrug resistance was observed in 83% of the Arcobacter spp. isolates. Our study detected Arcobacter spp. in Tunisian poultry; because of their multidrug resistance, these species may constitute a public health problem.

HIGHLIGHTS

Improved culture enrichment broth for isolation of Arcobacter-like species from the marine environment

Arcobacter-like species are found associated with many matrices, including shellfish in marine environments. The culture media and conditions play a major role in the recovery of new Arcobacter-like species. This study was aimed to develop a culture media for isolation and enhanced growth of Arcobacter-like spp. from marine and shellfish matrices. For this purpose, 14 different Arcobacter-like spp. mostly isolated from shellfish, were grown in 24 different formulations of enrichment broths. The enrichment broths consisted of five main groups based on the organic contents (fresh oyster homogenate, lyophilized oyster either alone or in combination with other standard media), combined with artificial seawater (ASW) or 2.5% NaCl. Optical density (OD_420nm) measurements after every 24 h were compared with the growth in control media (Arcobacter broth) in parallel. The mean and standard deviation were calculated for each species in each broth and statistical differences (p < 0.05) among broths were calculated by ANOVA. The results indicated that shellfish-associated Arcobacter-like species growth was significantly higher in Arcobacter broth + 50% ASW and the same media supplemented with lyophilized oysters. This is the first study to have used fresh or lyophilized oyster flesh in the enrichment broth for isolation of shellfish-associated Arcobacter-like spp.

Arcobacter: an emerging food-borne zoonotic pathogen, its public health concerns and advances in diagnosis and control - a comprehensive review

Arcobacter has emerged as an important food-borne zoonotic pathogen, causing sometimes serious infections in humans and animals. Newer species of Arcobacter are being incessantly emerging (presently 25 species have been identified) with novel information on the evolutionary mechanisms and genetic diversity among different Arcobacter species. These have been reported from chickens, domestic animals (cattle, pigs, sheep, horses, dogs), reptiles (lizards, snakes and chelonians), meat (poultry, pork, goat, lamb, beef, rabbit), vegetables and from humans in different countries. Arcobacters are implicated as causative agents of diarrhea, mastitis and abortion in animals, while causing bacteremia, endocarditis, peritonitis, gastroenteritis and diarrhea in humans. Three species including A. butzleri, A. cryaerophilus and A. skirrowii are predominantly associated with clinical conditions. Arcobacters are primarily transmitted through contaminated food and water sources. Identification of Arcobacter by biochemical tests is difficult and isolation remains the gold standard method. Current diagnostic advances have provided various molecular methods for efficient detection and differentiation of the Arcobacters at genus and species level. To overcome the emerging antibiotic resistance problem there is an essential need to explore the potential of novel and alternative therapies. Strengthening of the diagnostic aspects is also suggested as in most cases Arcobacters goes unnoticed and hence the exact epidemiological status remains uncertain. This review updates the current knowledge and many aspects of this important food-borne pathogen, namely etiology, evolution and emergence, genetic diversity, epidemiology, the disease in animals and humans, public health concerns, and advances in its diagnosis, prevention and control.

Virulence gene profiles of Arcobacter species isolated from animals, foods of animal origin, and humans in Andhra Pradesh, India

Aim::

This study aimed to detect putative virulence genes in Arcobacter species of animal and human origin.

Materials and Methods::

A total of 41 Arcobacter isolates (16 Arcobacter butzleri, 13 Arcobacter cryaerophilus, and 12 Arcobacter skirrowii) isolated from diverse sources such as fecal swabs of livestock (21), raw foods of animal origin (13), and human stool samples (7) were subjected to a set of six uniplex polymerase chain reaction assays targeting Arcobacter putative virulence genes (ciaB, pldA, tlyA, mviN, cadF, and cj1349).

Results::

All the six virulence genes were detected among all the 16 A. butzleri isolates. Among the 13 A. cryaerophilus isolates, cadF, ciaB, cj1349, mviN, pldA, and tlyA genes were detected in 61.5, 84.6, 76.9, 76.9, 61.5, and 61.5% of isolates, respectively. Among the 12 A. skirrowii isolates, cadF, ciaB, cj1349, mviN, pldA, and tlyA genes were detected in 50.0, 91.6, 83.3, 66.6, 50, and 50% of isolates, respectively.

Conclusion::

Putative virulence genes were detected in majority of the Arcobacter isolates examined. The results signify the potential of Arcobacter species as an emerging foodborne pathogen.

Occurrence of potentially pathogenic arcobacters in shellfish

Considering that several recent cases of human gastroenteritis have been associated with species from the Arcobacter genus, and that few data are currently available about the occurrence of this genus in Italian shellfish, the aim of the present study was to evaluate the occurrence of Arcobacter spp. and the presence of virulence-associated genes. The approach consisted of cultural and biomolecular (multiplex-PCR and 16S-RFLP) methods identifying isolates, followed by PCR assays aimed at the cadF, ciaB, cjl349, irgA, hecA putative virulence genes. Arcobacter spp. was detected in 16/70 (22.8%) shellfish samples. Specifically, Arcobacter spp. was highlighted in 10/42 (23.8%) mussel and in 6/28 (21.4%) clam samples. Subsequently, biomolecular assays revealed Arcobacter butzleri in 12/16 (75%) and Arcobacter cryaerophilus 1B in 4/16 (25%) isolates. PCRs aimed at the five putative virulence genes demonstrated widespread distribution of these genes among Arcobacter isolates and some differences from the results published by other authors. Our research provides more information regarding the health risks associated with the consumption of raw bivalve molluscs and underlines the need to implement an adequate control plan by performing intensive and continuous monitoring in order to guarantee human health.

Genotyping and genetic diversity of Arcobacter butzleri and Arcobacter cryaerophilus isolated from different sources by using ERIC-PCR from India

BACKGROUND

Arcobacters are important zoonotic pathogens and are transmitted through food and water. They are implicated in causing enteritis in animals and humans. Among the Arcobacter species, a wide genetic diversity has been documented, which reflects continuous evolving nature of these pathogens.

OBJECTIVES

To genotype and to know the genetic diversity of Arcobacter spp. (Arcobacter butzleri and Arcobacter cryaerophilus) isolated from different sources in India.

METHODS

Enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) was performed using genomic DNA of 49 Arcobacter isolates (27 A. butzleri and 22 A. cryaerophilus), recovered from a total of 506 samples of chicken meat, poultry skin, dairy cow milk and human stool as template and employing published primers.

RESULTS

ERIC sequence was found to be present in all the 27 A. butzleri isolates which were grouped into 18 subtypes, while it was present in 20 out of 22 A. cryaerophilus isolates which were grouped into 14 subtypes. Less variation was observed within sequences of both the Arcobacter species as revealed in dendrogram analysis. The genotyping of A. butzleri isolates showed the presence of 2-8 distinct bands (∼150 to ∼1600 bp), while A. cryaerophilus showed 1-10 distinct bands (∼120 to ∼2900 bp).

CONCLUSION

This study is the first report regarding genetic diversity of Indian Arcobacter isolates using ERIC-PCR. Close clustering between arcobacters of human and animal origin are indicative of probable zoonotic significance. So for these purposes, further explorative studies are suggested which would also help revealing the possibility of epidemiological relationships of different Arcobacter spp. as well as their public health concerns.