Detection of Arcobacter spp. in food products collected from Sicilia region: A preliminary study

Occurrence of Aliarcobacter spp. in fresh and pre-cut vegetables of common use in San José, Costa Rica

Aliarcobacter is a Gram-negative rod that can cause disease in both animals and humans. Several studies have evidenced its presence in a wide variety of foods. Given that the number of foodborne illness outbreaks linked to the consumption of vegetables has increased worldwide and that there is a lack of information about the occurrence of Aliarcobacter spp. in these, the aim of this study was to evaluate its presence and the occurrence of virulence factors in both fresh and ready-to-eat vegetable samples. 180 vegetable samples from Costa Rica were analyzed for the presence of Aliarcobacter spp., including 90 pre-cut vegetable packages and 90 fresh vegetables. Two (2.2%) of the isolates from pre-cut vegetables and 19 (21.1%) of the isolates obtained from fresh vegetables were confirmed as Aliarcobacter spp. One of the isolates from the pre-cut vegetable samples was identified as A. butzleri. For the fresh vegetables, 11 isolates were identified as A. skirrowii, one as A. butzleri, and the 7 remaining isolates could not be identified at a species level. There is an 87.5% positivity for hecA and 93.8% for pldA, virulence genes in strains isolated from fresh produce, contrasting with an absolute absence from pre-cut vegetable-isolated strains. These results evidence the presence of Aliarcobacter on fresh and pre-cut vegetables from Costa Rica and the potential hazard it might represent for public health.

Arcobacter species isolated from various seafood and water sources; virulence genes, antibiotic resistance genes and molecular characterization

Arcobacter spp. has gained clinical significance as an emerging diarrheagenic pathogen associated with water reservoirs in recent years. The complete clinical significance of Arcobacter remains rather speculative due to the virulence and antibiotic susceptibility of individual strains. This study aimed to assess the prevalence of Arcobacter spp. in fish, water, and shellfish. A total of 150 samples were collected from the Adana, Kayseri and Kahramanmaras provinces in Turkey. Arcobacter spp. was isolated from 32 (21%) of the 150 samples. The most prevalent species was A. cryaerophilus, 17 (56%), A. butzleri 13 (37%) and A. lacus 2 (6%). As a result, the ratios of the mviN, irgA, pldA, tlyA and hecA target genes were found as 17 (51%), 1 (3%), 7 (23%), 7 (23%), 1 (3%), respectively. While bla OXA-61, tetO and tetW were positive in all isolates, were found as mcr1/2/6, mcr3/7, and mcr5, genes %37.5, %25, and %34.3, respectively. Although in A. butzleri was found 10 (58%), 1 (3%), 3 (43%), 2 (28%) (mviN, irgA, pldA, and tlyA, respectively) virulence genes 7 (42%), 4 (57%), 5 (72%), 1 (3%) was found (mviN, irgA, tlyA, and hecA, respectively) virulence genes in A. cryoaerophilus. Moreover, was found for the mcr 1/2/6 7 (58%) genes, for the mcr 3/7 genes 3 (38%) in A. butzleri. In A. cryoaerophilus was found for the mcr 1/2/6 genes 5 (42%), for the mcr 3/7 genes 5 (62%), and for the mcr 5 gene 10 (100%). Thus, the current study indicated that the existence of Arcobacter spp. isolated from fish and mussel samples may pose a potential risk to public health.

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.

Characterization of Microbiological Quality of Whole and Gutted Baltic Herring

There is growing interest in Baltic herring (Clupea harengus membras) and other undervalued, small-sized fish species for human consumption. Gutting or filleting of small-sized fish is impractical; hence, the aim of this study was to explore the suitability of the whole (ungutted) herring for food use. The microbiological quality of commercially fished whole and gutted herring was analysed with culture-dependent methods combined with identification of bacterial isolates with MALDI-TOF Mass Spectrometry and culture-independent 16S rRNA gene amplicon sequencing. Whole and gutted herring had between 2.8 and 5.3 log₁₀ CFU g⁻¹ aerobic mesophilic and psychrotrophic bacteria and between 2.2 and 5.6 log₁₀ CFU g⁻¹ H₂S-producing bacteria. Enterobacteria counts remained low in all the analysed herring batches. The herring microbiota largely comprised the phyla Proteobacteria, Firmicutes, and Actinobacteria (71.7% to 95.0%). Shewanella, Pseudomonas, and Aeromonas were the most frequently isolated genera among the viable population; however, with the culture-independent approach, Shewanella followed by Psychrobacter were the most abundant genera. In some samples, a high relative abundance of the phylum Epsilonbacteraeota, represented by the genus Arcobacter, was detected. This study reports the bacterial diversity present in Baltic herring and shows that the microbiological quality was acceptable in all the analysed fish batches.

Identification of colonies of cultured shellfish-associated Arcobacter species by Elastic Light Scatter Analysis

An increasing number of Arcobacter species (including several regarded as emerging human foodborne pathogens) have been isolated from shellfish, an important food commodity. A method to distinguish these species and render viable isolates for further analysis would benefit epidemiological and ecological studies. We describe a method based on Elastic Light Scatter analysis (ELSA) for the detection and discrimination of eleven shellfish-associated Arcobacter species. Although substantive differences in the growth rates of some taxa were seen, ELSA was able to differentiate all the species studied, apart from some strains of A. butzleri and A. cryaerophilus, which were nonetheless distinguished from all other species examined. ELSA appears to be a promising new approach for the detection and identification of Arcobacter species in shellfish and may also be applicable for studies in other foods and matrices.

A Systematic Analysis of Research on Arcobacter: Public Health Implications from a Food-Environment Interphase Perspective

This review maps the global research landscape of the public health implications of Arcobacter from the food–environment interphase using content analytics and integrated science mapping. The search term “Arcobacter” was used to retrieve relevant articles published in Web of Science and Scopus between 1991 to 2019. The number of articles included in the review was 524, with 1304 authors, 172 journal sources, and a collaborative index of 2.55. The annual growth rate of the publications was 9.74%. The most contributing author in the field was Houf K., with 40 publications, 26 h-index, and 2020 total citations. The most productive country was the USA (13.33%). The majority of the articles were published in English (96%) and in the Journal of Food Protection (8.02%). The highest research outputs were in the field of Microbiology (264). The frequently occurred keywords were Arcobacter, poultry, shellfish, cattle, and chicken. This study revealed a fair increase in the growth rate of Arcobacter-related research—especially in the area of isolation and detection of the pathogen in foods and food environments, as well as the pathogenesis and genetic diversity of the pathogen. Research themes in the area of prevalence and epidemiology seem to be underexplored.

Prevalence, resistance to antimicrobials, and antibiotypes of Arcobacter species recovered from retail meat in Wasit marketplaces in Iraq

Background and Aim: Arcobacter is a food-borne pathogen associated with human and animal infections. In Iraq, these infections and their adverse effects on public health have not been well investigated. For this reason, as well as to submit data on the resistance to antimicrobials and antibiotypes of the Arcobacter spp. and their occurrence in retail meat in the Wasit marketplaces, this study was undertaken. Materials and Methods: A total of 83 samples of fresh raw (n=35) and chilled meat (n=48) were purchased randomly from marketplaces in various regions of the Wasit Governorate. Bacterial detection was conducted using cultural methods, biochemical analysis, and the Oxoid Biomedical Identification System Campy. Confirmation of these bacteria at the species level was performed using the multiplex polymerase chain reaction method. Susceptibility of the Arcobacter spp. to antimicrobials was investigated in 11 isolates comprising Arcobacter butzleri (n=9) and Arcobacter cryaerophilus (n=2) using the Kirby–Bauer disk diffusion method. Results: A total of 32 (38.6%) of the 83 fresh raw and chilled meat samples tested positive for Arcobacter spp.; of those, 27 (84.4%) and 5 (15.6%) were recognized as A. butzleri and A. cryaerophilus, respectively. Maximum resistance was perceived, respectively, to tetracycline, erythromycin, and ampicillin (90.9%, 81.8%, and 81.8%, respectively). In contrast, a low resistance rate against fluoroquinolones up to 9.09% was found. Antibiograms of the A. butzleri and A. cryaerophilus isolates yielded ten antibiotypes. The vast majority of the isolates (90.91%) were resistant to no fewer than three classes of antimicrobials, and 27.3% of these showed resistance to six antibiotics. A total of 91% of the analyzed isolates had a multiple antibiotic resistance index score between 0.27 and 0.73. Conclusion: Our outcomes demonstrated that retail meat can be a prospective vehicle for pathogenic Arcobacter, making these products a possible risk to human health. Our outcomes postulate that the contamination of retail meats by pathogenic Arcobacter is a global public health concern, particularly with the growing resistance to life-saving drugs, and emphasizes consumer understanding about the quality and safety of these products. To achieve healthy food products, good management practices, and successful control approaches must be implemented across the entire food chain, not only to protect consumers from these contaminants but also to minimize the risk of drug resistance.

Occurrence and characterization of Arcobacter spp. from ready-to-eat vegetables produced in Southern Italy

Given that the number of foodborne illness outbreaks linked to the consumption of ready-to-eat vegetables has been widely documented and considering that data on the occurrence of Arcobacter spp. in such foodstuffs are lacking, the aim of the present study was to evaluate the presence of Arcobacter spp. and the occurrence of virulence factors as well as to genotype Arcobacter spp. in ready-to-eat (RTE) vegetable samples, using cultural and biomolecular assays. Arcobacter spp. was detected in 16/110 (14.5%) samples, with A. butzleri being detected in 15/16 and A. cryaerophilus in 1/16 isolates. PCRs aimed at the nine putative virulence genes demonstrated widespread distribution of such genes among A. butzleri and A. cryaerophilus isolates. In addition, multilocus sequence type (MLST) analysis revealed a low genetic diversity within the arcobacters isolates. The results underline the need to develop an appropriate surveillance system based on biomolecular characterization for an integrated microbiological risk assessment of ready-toeat vegetables, and consequently of composite foods.

Occurrence and Antimicrobial Resistance of Arcobacter spp. Recovered from Aquatic Environments

Arcobacter spp. are emerging waterborne and foodborne zoonotic pathogens responsible for gastroenteritis in humans. In this work, we evaluated the occurrence and the antimicrobial resistance profile of Arcobacter isolates recovered from different aquatic sources. Besides, we searched for Arcobacter spp. in seaweeds and the corresponding seawater samples. Bacteriological and molecular methods applied to 100 samples led to the isolation of 28 Arcobacter isolates from 27 samples. The highest prevalence was detected in rivers followed by artificial ponds, streams, well waters, and spring waters. Seaweeds contained a higher percentage of Arcobacter than the corresponding seawater samples. The isolates were identified as Arcobacter butzleri (96.4%) and Arcobacter cryaerophilus (3.6%). All the isolates showed a multi-drug resistance profile, being resistant to at least three different classes of antibiotics. Molecular analysis of genetic determinants responsible for tetracycline resistance in nine randomly chosen isolates revealed the presence of tetO and/or tetW. This work confirms the occurrence and the continuous emergence of antibiotic-resistant Arcobacter strains in environmental samples; also, the presence of quinolone-resistant Arcobacter spp. in aquatic sources used for water supply and irrigation represents a potential risk for human health.

Arcobacter butzleri: Up-to-date taxonomy, ecology, and pathogenicity of an emerging pathogen

Arcobacter butzleri, recently emended to the Aliarcobacter butzleri comb. nov., is an emerging pathogen causing enteritis, severe diarrhea, septicaemia, and bacteraemia in humans and enteritis, stillbirth, and abortion in animals. Since its recognition as emerging pathogen on 2002, advancements have been made in elucidating its pathogenicity and epidemiology, also thanks to advent of genomics, which, moreover, contributed in emending its taxonomy. In this review, we provide an overview of the up-to-date taxonomy, ecology, and pathogenicity of this emerging pathogen. Moreover, the implication of A. butzleri in the safety of foods is pinpointed, and culture-dependent and independent detection, identification, and typing methods as well as strategies to control and prevent the survival and growth of this pathogen are provided.