Resistant Campylobacter Research Articles

Resistance to Antibiotics in Thermophilic Campylobacters.

Campylobacter jejuni (C. jejuni) is one of the most frequent causes of bacterial enterocolitis globally. The disease in human is usually self-limiting, but when complications arise antibiotic therapy is required at a time when resistance to antibiotics is increasing worldwide. Mechanisms of antibiotic resistance in bacteria are diverse depending on antibiotic type and usage and include: enzymatic destruction or drug inactivation; alteration of the target enzyme; alteration of cell membrane permeability; alteration of ribosome structure and alteration of the metabolic pathway(s). Resistance of Campylobacter spp. to antibiotics, especially fluoroquinolones is now a major public health problem in developed and developing countries. In this review the mechanisms of resistance to fluoroquinolones, macrolides, tetracycline, aminoglycoside and the role of integrons in resistance of Campylobacter (especially at the molecular level) are discussed, as well as the mechanisms of resistance to β-lactam antibiotics, sulphonamides and trimethoprim. Multiple drug resistance is an increasing problem for treatment of campylobacter infections and emergence of resistant strains and resistance are important One Health issues.

Transmission dynamics of an antimicrobial resistant Campylobacter jejuni lineage in New Zealand’s commercial poultry network

Understanding the relative contribution of different between-farm transmission pathways is essential in guiding recommendations for mitigating disease spread. This study investigated the association between contact pathways linking poultry farms in New Zealand and the genetic relatedness of antimicrobial resistant Campylobacter jejuni Sequence Type 6964 (ST-6964), with the aim of identifying the most likely contact pathways that contributed to its rapid spread across the industry. Whole-genome sequencing was performed on 167C. jejuni ST-6964 isolates sampled from across 30 New Zealand commercial poultry enterprises. The genetic relatedness between isolates was determined using whole genome multilocus sequence typing (wgMLST). Permutational multivariate analysis of variance and distance-based linear models were used to explore the strength of the relationship between pairwise genetic associations among the C. jejuni isolates and each of several pairwise distance matrices, indicating either the geographical distance between farms or the network distance of transportation vehicles. Overall, a significant association was found between the pairwise genetic relatedness of the C. jejuni isolates and the parent company, the road distance and the network distance of transporting feed vehicles. This result suggests that the transportation of feed within the commercial poultry industry as well as other local contacts between flocks, such as the movements of personnel, may have played a significant role in the spread of C. jejuni. However, further information on the historical contact patterns between farms is needed to fully characterise the risk of these pathways and to understand how they could be targeted to reduce the spread of C. jejuni.

Occurrence and multidrug resistance of Campylobacter spp. at duck farms and associated environmental and anthropogenic risk factors in Bangladesh

BackgroundThe alarming rise in multi-drug resistant (MDR) zoonotic pathogens, including Campylobacter spp., has been threatening the health sector globally. In Bangladesh, despite rapid growth in poultry sector little is known about the potential risks of zoonotic pathogens in homestead duck flocks. The aim of this study was to understand the occurrence, species diversity, and multi-drug resistance in Campylobacter spp., and identify the associated risk factors in duck farms in Bangladesh.MethodsThe study involved 20 duck farms at 6 sub-districts of Mymensingh, Bangladesh. Monthly occurrence of Campylobacter spp. in potential sources at the farms during February-September, 2018, was detected by culture and PCR-based methods. Campylobacter isolates were examined for resistance to different antimicrobials. Risk factors, concerning climatic and environmental disposition, farm management, and anthropogenic practices, of Campylobacter infection were estimated by participatory epidemiological tools.ResultsOccurrence of Campylobacter spp. was detected in overall 36.90% (155/420) samples, more frequently in drinking water (60%, 30/50), followed by cloacal swab (37.50%, 75/200), egg surface swab (35%, 35/100) and soil of the duck resting places (30%, 15/50) but was not detected in feed samples (n = 20). PCR assays distinguished the majority (61.30%, 95/155) of the isolates as C. coli, while the rest (38.70%, 60/155) were C. jejuni. Notably, 41.7% (25/60) and 31.6% (30/95) strains of C. jejuni and C. coli, respectively, were observed to be MDR. The dynamics of Campylobacter spp., distinctly showing higher abundance during summer and late-monsoon, correlated significantly with temperature, humidity, and rainfall, while sunshine hours had a negative influence. Anthropogenic management-related factors, including, inadequate hygiene practices, use of untreated river water, wet duck shed, flock age (1–6 months), and unscrupulous use of antimicrobials were identified to enhance the risk of MDR Campylobacter infection.ConclusionThe present study clearly demonstrates that duck farms contribute to the enhanced occurrence and spread of potentially pathogenic and MDR C. coli and C. jejuni strains and the bacterial dynamics are governed by a combined interaction of environmental and anthropogenic factors. A long-term holistic research at the environment-animal-human interface would be integral to divulge health risk reduction approaches tackling the spread of Campylobacter spp. from duck farms.

Molecular Detection of Fluoroquinolone Resistance among Multidrug-, Extensively Drug-, and Pan-Drug-Resistant Campylobacter Species in Egypt.

In recent times, resistant foodborne pathogens, especially of the Campylobacter species, have created several global crises. These crises have been compounded due to the evolution of multidrug-resistant (MDR) bacterial pathogens and the emergence of extensively drug-resistant (XDR) and pan-drug-resistant (PDR) strains. Therefore, this study aimed to investigate the development of resistance and the existence of both XDR and PDR among Campylobacter isolates. Moreover, we explored the use of the polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) technique for the detection of fluoroquinolone (FQ)-resistant Campylobacter isolates. A total of 120 Campylobacter isolates were identified depending on both phenotypic and genotypic methods. Of note, cefoxitin and imipenem were the most effective drugs against the investigated Campylobacter isolates. Interestingly, the majority of our isolates (75%) were MDR. Unfortunately, both XDR and PDR isolates were detected in our study with prevalence rates of 20.8% and 4.2%, respectively. All FQ-resistant isolates with ciprofloxacin minimum inhibitory concentrations ≥4 µg/mL were confirmed by the genetic detection of gyrA chromosomal mutation via substitution of threonine at position 86 to isoleucine (Thr-86-to-Ile) using the PCR-RFLP technique. Herein, PCR-RFLP was a more practical and less expensive method used for the detection of FQ resistant isolates. In conclusion, we introduced a fast genetic method for the identification of FQ-resistant isolates to avoid treatment failure through the proper description of antimicrobials.

Epidemiologic characteristics of <i>Campylobacter</i> infections in high-income countries: a systematic review

Introduction. The Campylobacter is the most common bacterial cause of foodborne illnesses in high-income countries. In contrast to other infectious diseases, the number of Campylobacter cases has increased in developed countries over the last ten years. A systematic review has been conducted to identify the factors contributing to incidence of Campylobacter infection in developed countries and to estimate it by age, sex, geography, and season.Materials and methods. The review was limited to studies published in English from 2010-2021; eight nationwide surveillance and register-based cohort studies, which met the selection criteria, were included in the review.Results. While the highest incidence of Campylobacter infection was reported among young children living in rural areas, the highest number of Campylobacter cases among adults was recorded in urban settings. Nevertheless, population-wise, children and older adults are most affected, while the incidence rates are higher in males than in females, with cases peaking every summer.Conclusion. Campylobacter infection is a public health concern in high-income countries, being difficult to eradicate and having become an urgent challenge to the existing well-developed surveillance systems. Additionally, the threat of antibiotic resistance in Campylobacter is growing at an alarming rate. The reasons behind Campylobacter affecting more men than women as well as the age and geographic distribution of the infection still need thorough research.

Aminoglycoside Resistance and Possible Mechanisms in Campylobacter Spp. Isolated From Chicken and Swine in Jiangsu, China.

Campylobacter is a major food-borne pathogen in humans, and previous studies reported a high prevalence of gentamicin-resistant Campylobacter isolates from food-producing animals in China. This study aimed to investigate the aminoglycoside resistance of Campylobacter isolated from chicken and swine in Jiangsu province, China and understand the possible mechanisms responsible for aminoglycoside resistance. One hundred and eighty-five Campylobacter isolates of chicken and swine origins in 2017 and 2018 were analyzed for gentamicin and kanamycin resistance. Some aminoglycoside resistance genes were selected for PCR detection in all strains. The genomic DNAs of two strains with high resistance to gentamicin were used as donors to subject C. jejuni NCTC11168 to natural transformation. The transformants were investigated by whole-genome sequencing and analyzed comparatively with C. jejuni NCTC11168. In total, 30.5% (29/95) of C. jejuni isolates and 42.2% (38/90) of C. coli isolates were resistant to gentamicin and kanamycin. The prevalence of the aph(2")-If gene and aac(6')-Ie/aph(2")-Ia gene was 65.4% (121/185) and 36.2% (67/185) in Campylobacter isolates, respectively. The aadE-sat4-aphA-3 cluster was identified in 8.7% (8/92) and 20.4% (19/93) of all Campylobacter isolates in each year. With each donor DNA, aminoglycoside-resistant transformants were obtained. The transformants showed ≥128-fold increases in the MICs of gentamicin, kanamycin, and tobramycin. A 5200-bp segment was found to be inserted between the highly conserved genes Cj0299 and panB of Campylobacter. A total of 9.7% (18/185) strains showing high resistance to aminoglycosides had this segment by PCR detection. The genetic diversity of the insertion-fragment positive strains was determined by MLST, and seven sequence types were identified for these strains.

Prevalence and antimicrobial resistance of Campylobacter from wild birds of prey in Spain

Wild birds have been identified as a relevant reservoir of Campylobacter spp., therefore, a potential source of infection in humans and domestic animals. The objective of this study was to determine the occurrence of Campylobacter spp. on birds of prey in Spain. In addition, antibiotic resistance profiles of the isolates were evaluated. A total of 689 specimens of 28 raptor species were analyzed, with a resulting individual prevalence of 7.5%. C. jejuni was the most frequently isolated species (88.5%), followed by C. coli and C. lari (3.8% each). The occurrence of Campylobacter was significantly higher (p < 0.05) in nocturnal birds of prey (15.3%), in spring season (12.2%) and in carnivorous species (9.4%). Isolates displayed a remarkable resistance to nalidixic acid (69.9%), ciprofloxacin (69.9%), and tetracycline (55.6%), and a low resistance to streptomycin (6.7%).Our findings highlight the importance of birds of prey as reservoirs of Campylobacter strains and their significant role as carriers of antimicrobial resistance.

Natural Horizontal Gene Transfer of Antimicrobial Resistance Genes in Campylobacter spp. From Turkeys and Swine.

Antibiotic-resistant Campylobacter constitutes a serious threat to public health. The clonal expansion of resistant strains and/or the horizontal spread of resistance genes to other strains and species can hinder the clinical effectiveness of antibiotics to treat severe campylobacteriosis. Still, gaps exist in our understanding of the risks of acquisition and spread of antibiotic resistance in Campylobacter. While the in vitro transfer of antimicrobial resistance genes between Campylobacter species via natural transformation has been extensively demonstrated, experimental studies have favored the use of naked DNA to obtain transformants. In this study, we used experimental designs closer to real-world conditions to evaluate the possible transfer of antimicrobial resistance genes between Campylobacter strains of the same or different species (Campylobacter coli or Campylobacter jejuni) and originating from different animal hosts (swine or turkeys). This was evaluated in vitro through co-culture experiments and in vivo with dual-strain inoculation of turkeys, followed by whole genome sequencing of parental and newly emerged strains. In vitro, we observed four independent horizontal gene transfer events leading to the acquisition of resistance to beta-lactams (blaOXA), aminoglycosides [aph(2′′)-If and rpsL] and tetracycline [tet(O)]. Observed events involved the displacement of resistance-associated genes by a mutated version, or the acquisition of genomic islands harboring a resistance determinant by homologous recombination; we did not detect the transfer of resistance-carrying plasmids even though they were present in some strains. In vivo, we recovered a newly emerged strain with dual-resistance pattern and identified the replacement of an existing non-functional tet(O) by a functional tet(O) in the recipient strain. Whole genome comparisons allowed characterization of the events involved in the horizontal spread of resistance genes between Campylobacter following in vitro co-culture and in vivo dual inoculation. Our study also highlights the potential for antimicrobial resistance transfer across Campylobacter species originating from turkeys and swine, which may have implications for farms hosting both species in close proximity.

A Review of Campylobacter Infections in Dogs

Campylobacter spp. are important bacterial enteropathogens that cause diarrhea in dogs with the predominant species being Campylobacter jejuni, C. helveticus, and C. upsaliensis. Although campylobacteriosis is subclinical in many dogs, some may develop moderate to mild enteritis. Puppies, kenneled dogs, and dogs with concurrent conditions are highly susceptible to Campylobacter-associated diarrhea. Diagnosis of suspected Campylobacter-associated diarrhea in dogs poses a challenge to veterinarians as the fecal enteric panels are costly, require technical knowledge, and are time consuming, however molecular approaches for diagnosing the Campylobacter spp. infections are becoming readily available and can help in accurate and fast diagnosis. Campylobacter spp. are amongst the prioritized human and animal pathogens with regards to antimicrobial resistance. The rise and spread of antimicrobial resistance threatens the effective treatment and control of Campylobacter infections. Multi-drug resistance Campylobacter spp. have been isolated from dogs therefore treatment should only be administered where necessary. In conclusion, understanding the epidemiology, diagnosis, treatment and zoonotic potential of Campylobacter spp. will enable small animal practitioners include them among the differential diagnoses of diarrheic diseases in dogs.

Phenotypic and Molecular Patterns of Resistance among Campylobacter coli and Campylobacter jejuni Isolates, from Pig Farms.

Simple SummaryCampylobacter spp. has been the leading cause of human diarrhea in EU since 2005. Although poultry and poultry meat are considered as the primary source of transmission of campylobacteriosis to humans, pigs can be a significant reservoir of the pathogen, as well. Moreover, the increase of antibiotic resistance in the specific pathogen, especially against fluroquinolones and macrolides is considered a significant threat for public health. The purpose of the current study was to evaluate and molecularly characterize the antimicrobial resistance of Campylobacter infection in pig farms in Greece at both phenotypic and molecular level.The purpose of this research was to characterize the antibiotic resistance patterns of Campylobacter spp. isolated from commercial farrow to finish farms in Greece, and analyze the relevant molecular resistance mechanisms among the resistant Campylobacter isolates. Susceptibility testing to five different classes of antibiotics was performed in 100 C. coli and 100 C. jejuni, previously isolated and identified. All isolates were found susceptible to meropenem. Very high rates of resistance were recorded for tetracyclines (84.5%), medium rates of resistance were recorded regarding quinolones (23%), and low and very low rates of resistance were identified for macrolides such as erythromycin and aminoglycosides (12% and 4%, respectively). Only 12.5% of the Campylobacter isolates displayed MDR. Regarding the molecular mechanisms of resistance, all ciprofloxacin resistant isolates hosted the mutant type Thr-86-Ile region of the quinolone resistance-determining region (QRDR) of the gyrA gene. In all erythromycin resistant isolates, the transitional mutations A2075G and A2074C in the 23S rRNA gene were only amplified. Molecular screening of tetracycline resistance genes indicated that the vast majority of Campylobacter isolates (92.3%) were positive for the tet(O) gene. In summary, these findings and especially the very high and medium rates of resistance for tetracyclines and fluroquinolones, respectively recommend that a continuous monitoring of Campylobacter isolates susceptibility in combination with the proper use of antimicrobials in livestock production is of great importance for public health.

Genotypic analyses and antimicrobial resistance profiles of Campylobacter jejuni from crows (Corvidae) of United States and India reflect their respective local antibiotic burdens.

The study examined the hypothesis that crow-borne Campylobacter can function as environmental reservoirs and indicators of antibiotic resistance (AR) determinants circulating in a human population. Two species of crows from Washington (WA), United States, and Kolkata, India, respectively, were examined for their ability to carry antibiotic resistant Campylobacter. Campylobacter jejuni was the only species isolated by selective agar plating from crow faecal samples. Disk diffusion method used to compare the AR profile of the isolates showed tetracycline (TET) resistance to be the most prevalent (27%) among WA isolates, followed by ciprofloxacin (CIP; 24%). Among Kolkata isolates, nalidixic acid resistance was most common (36%), followed by CIP (27%). The AR profile demonstrated by crow isolates of WA reflects those reported by the US National Antimicrobial Resistance Monitoring System for human isolates (2007-2011), where resistance to TET was most prevalent (≈45%), followed by quinolones (≈24%). The Kolkata crow isolates reflected the AR profile of human clinical isolates from India, where 97% resistance was shown to quinolones, followed by TET (18%). Multilocus sequence typing of 37 isolates, including 11 water isolates from the crow roost area, showed 24 different sequence types (STs). Seventeen of these were previously found in wild birds, 2 in human diarrhoea, 4 in poultry and 8 in environmental water. One isolate was found in both water and faeces, though from different sites within WA. The results indicate that crows most likely acquire the AR from anthropogenic sources. Although they are colonized by specific STs, rarely isolated from humans, they can facilitate the spread of AR. By studying two areas in different continents, this research demonstrates that Campylobacter borne by crows can function as environmental reservoirs and indicators of AR determinants that circulate in a human population. This information will be of importance to scientists from the medical and poultry industries.

Occurrence and antimicrobial resistance of Campylobacter isolates from broiler chicken and slaughter house environment in India

Campylobacteriosis is among the most frequently reported foodborne zoonoses. A total of 848 samples were screened for Campylobacter spp. and occurrence was found to be 8.7%, 2.3% and 1.65% in broiler cecum samples, chicken meat samples and slaughter house environment swabs, respectively. High level of antimicrobial resistance was found against tetracycline (64.1%), doxycycline (54.4%), ampicillin (46.6%), nalidixic acid (42.7%), kanamycin (35.9%), and ciprofloxacin (33.33%). Resistance to co-amoxiclav (19.4%) and erythromycin (21.4%) was less common. The MAR index of the isolates was in the range of 0.11–0.78. Multi-drug resistance was observed in 54.4% of the isolates, with 53.2% C. jejuni and 55.3% C. coli isolates found resistant against three or more classes of antimicrobials. Presence of mutations in gyrA and 23S rRNA genes was investigated, which revealed that all the fluoroquinolone resistant isolates possessed Thr-86-Ile point mutation, whereas only 68% of erythromycin resistant isolates had A2075G mutation. The tetO gene was present in 91.7% tetracycline resistant isolates and bla OXA-61 gene was detected in 97.9% of the ampicillin resistant isolates. The occurrence of antimicrobial resistant Campylobacter spp. in broiler chicken samples and slaughter house settings is a public health risk and calls for judicial use of antimicrobials.

Bacteriophage Therapy to Reduce Colonization of Campylobacterjejuni in Broiler Chickens before Slaughter.

Campylobacteriosis is the most commonly reported gastrointestinal disease in humans. Campybacter jejuni is the main cause of the infection, and bacterial colonization in broiler chickens is widespread and difficult to prevent, leading to high risk of occurrence in broiler meat. Phage therapy represents an alternative strategy to control Campylobacter in poultry. The aim of this work was to assess the efficacy of two field-isolated bacteriophages against experimental infections with an anti-microbial resistant (AMR) Campylobacter jejuni strain. A two-step phage application was tested according to a specific combination between chickens’ rearing time and specific multiplicities of infections (MOIs), in order to reduce the Campylobacter load in the animals at slaughtering and to limit the development of phage-resistant mutants. In particular, 75 broilers were divided into three groups (A, B and C), and phages were administered to animals of groups B and C at day 38 (Φ 16-izsam) and 39 (Φ 7-izsam) at MOI 0.1 (group B) and 1 (group C). All broilers were euthanized at day 40, and Campylobacter jejuni was enumerated in cecal contents. Reductions in Campylobacter counts were statistically significant in both group B (1 log10 colony forming units (cfu)/gram (gr)) and group C (2 log10 cfu/gr), compared to the control group. Our findings provide evidence about the ability of phage therapy to reduce the Campylobacter load in poultry before slaughtering, also associated with anti-microbial resistance pattern.

Monitoring of Antimicrobial Resistance to Aminoglycosides and Macrolides in Campylobacter coli and Campylobacter jejuni From Healthy Livestock in Spain (2002–2018)

Antimicrobial resistance (AMR) in Campylobacter spp. (Campylobacter coli and Campylobacter jejuni) is a concern due to its importance in public health, particularly when it involves aminoglycosides and macrolides, drugs of choice for treatment of human cases. Co-resistance to these two antimicrobial classes involves transfer of genetic elements and/or acquisition of mutations in different genetic loci, which can in turn spread through vertical or horizontal gene transfer (HGT) phenomena, with each route having different potential implications. This study aimed at evaluating the association between the presence of phenotypic resistance to these two antimicrobial classes in C. coli and C. jejuni recovered from livestock at slaughterhouses in Spain (as part of the AMR surveillance program), and at assessing the genetic heterogeneity between resistant and susceptible isolates by analysing the “short variable region” (SVR) of the flaA gene. Over the 2002–2018 period, antimicrobial susceptibility test results from 10,965 Campylobacter isolates retrieved from fecal samples of broilers, turkeys, pigs and cattle were collected to compare the proportion of resistant isolates and the Minimum Inhibitory Concentrations (MICs) against six antimicrobials including gentamicin (GEN), streptomycin (STR), and erythromycin (ERY). AMR-associated genes were determined for a group of 51 isolates subjected to whole genome sequencing, and the flaA SVR of a subset of 168 isolates from all hosts with different resistotypes was used to build a Neighbor-Joining-based phylogenetic tree and assess the existence of groups by means of “relative synonymous codon usage” (RSCU) analysis. The proportion of antimicrobial resistant isolates to both, aminoglycosides and macrolides, varied widely for C. coli (7–91%) and less for C. jejuni (all hosts 0–11%). Across hosts, these proportions were 7–56% in poultry, 12–82% in cattle, and 22–91% in pigs for C. coli and 0–8% in poultry and 1–11% in cattle for C. jejuni. Comparison of the MIC distributions revealed significant host-specific differences only for ERY in C. jejuni (p = 0.032). A significant association in the simultaneous presentation of AMR to both antimicrobial classes was observed across hosts/bacterial species. The flaA gene analysis showed clustering of isolates sharing resistotype and to a lesser degree bacterial species and host. Several resistance markers associated with resistance to aminoglycosides and macrolides were found among the sequenced isolates. The consistent association between the simultaneous presentation of AMR to aminoglycosides and macrolides in all hosts could be due to the persistence of strains and/or resistance mechanisms in Campylobacter populations in livestock over time. Further studies based on whole genome sequencing are needed to assess the epidemiological links between hosts and bacterial strains.

High-throughput sequencing reveals genetic determinants associated with antibiotic resistance in Campylobacter spp. from farm-to-fork.

Campylobacter species are one of the most common causative agents of gastroenteritis worldwide. Resistance against quinolone and macrolide antimicrobials, the most commonly used therapeutic options, poses a serious risk for campylobacteriosis treatment. Owing to whole genome sequencing advancements for rapid detection of antimicrobial resistance mechanisms, phenotypic and genotypic resistance trends along the “farm-to-fork” continuum can be determined. Here, we examined the resistance trends in 111 Campylobacter isolates (90 C. jejuni and 21 C. coli) recovered from clinical samples, commercial broiler carcasses and dairy products in Cairo, Egypt. Multidrug resistance (MDR) was observed in 10% of the isolates, mostly from C. coli. The prevalence of MDR was the highest in isolates collected from broiler carcasses (13.3%), followed by clinical isolates (10.5%), and finally isolates from dairy products (4%). The highest proportion of antimicrobial resistance in both species was against quinolones (ciprofloxacin and/or nalidixic acid) (68.4%), followed by tetracycline (51.3%), then erythromycin (12.6%) and aminoglycosides (streptomycin and/or gentamicin) (5.4%). Similar resistance rates were observed for quinolones, tetracycline, and erythromycin among isolates recovered from broiler carcasses and clinical samples highlighting the contribution of food of animal sources to human illness. Significant associations between phenotypic resistance and putative gene mutations was observed, with a high prevalence of the gyrA T86I substitution among quinolone resistant isolates, tet(O), tet(W), and tet(32) among tetracycline resistant isolates, and 23S rRNA A2075G and A2074T mutations among erythromycin resistant isolates. Emergence of resistance was attributed to the dissemination of resistance genes among various lineages, with the dominance of distinctive clones. For example, sub-lineages of CC828 in C. coli and CC21 in C. jejuni and the genetically related clonal complexes ‘CC206 and CC48’ and ‘CC464, CC353, CC354, CC574’, respectively, propagated across different niches sharing semi-homogenous resistance patterns.

Highly Prevalent Multidrug-Resistant Campylobacter spp. Isolated From a Yellow-Feathered Broiler Slaughterhouse in South China.

The purpose of this study was to investigate the prevalence, antimicrobial resistance, virulence genes, and genetic diversity of Campylobacter spp. along the yellow-feathered broiler slaughtering line in Southern China from December 2018 to June 2019. A total of 157 Campylobacter spp. isolates were identified from 1,102 samples (including 53.6% (75/140) of live chicken anal swab samples, 27.5% (44/160) of defeathering samples, 18.1% (29/160) of evisceration samples, 2.1% (3/140) of washing samples, 1.4% (2/140) of chilling samples, and 1.1% (4/362) of environmental samples). The prevalence of Campylobacter spp. was 14.2%, including 43.9% Campylobacter jejuni, 53.5% Campylobacter coli, and 2.5% other Campylobacter species. The highest antimicrobial resistance rate was found to be against sulfamethoxazole (138/157, 87.9%), and 90.4% (142/157) of the isolates were multidrug resistant (MDR). Examination of resistance-related genes revealed the double base mutated Thr-86-Ile, which informed ACA-TTA, with an Arg-79-Lys substitution in gyrA. Eleven virulence-associated genes (cadF, cdtA, cdtB, ciaB, flaA, imaA, dnaJ, plaA, virB11, racR, and cdtC) were also detected by a polymerase chain reaction (PCR) analysis, and cadF (81.5%) was the most prevalent. Based on an analysis of pulsed-field gel electrophoresis (PFGE) results, we found that Campylobacter spp. could be cross-contaminated throughout the entire slaughtering line. These results show that it is imperative to study the Campylobacter spp. from the yellow-feathered broiler along the slaughtering line in China to develop preventative and treatment measures for the poultry industry, as well as food safety and public health.

Association of Antimicrobial Resistance in Campylobacter spp. in Broilers and Turkeys with Antimicrobial Use.

We investigated trends in antimicrobial resistance (AMR) in Campylobacter jejuni and Campylobacter coli in poultry between 2010 and 2016 in Germany and their association with antimicrobial use. Campylobacter had been isolated from the caeca of broilers and turkeys at slaughter by regional laboratories according to current ISO methods in the framework of a national monitoring program. Isolates were submitted to the National Reference Laboratory for Campylobacter and tested for AMR using broth microdilution methods. Minimum inhibitory concentrations were evaluated according to epidemiological cut-off values. Antimicrobial use (AMU) data from 2014 to 2016 were taken from a government report. AMR was higher in C. coli than in C. jejuni and higher in turkeys than in broilers. AMR was highest to tetracycline and the tested (fluoro)quinolones while it was rare to gentamicin in both bacterial species, infrequent to erythromycin in C. jejuni, and moderate in C. coli. AMR to tetracycline and erythromycin decreased over time while it increased to (fluoro)quinolones. An association of AMU and AMR was observed for resistance to tetracycline and erythromycin, while it was not observed for the aminoglycosides. Resistance to nalidixic acid and ciprofloxacin increased despite a decrease of fluoroquinolone use between 2014 and 2016, indicating that other factors have a strong influence on resistance to (fluoro)quinolones in Campylobacter.

Occurrence of Antimicrobial Resistance in Foodborne Bacteria (Campylobacter and E. coli): A Food Safety Issue and Public Health Hazard

Campylobacter and Escherichia coli (E. coli) are prominent bacterial causes of human gastroenteritis in the developing countries and the emergence of antibiotic resistance of these bacteria has been widely reported to be on the increase, particularly because of the increase in the number of resistant Campylobacter and E. coli isolated from human infections. The widespread use of antimicrobial drugs for therapeutic, prophylactic, and preventive purposes in modern food animal husbandry is a great concern in terms of the development of antibiotic resistance in many bacteria, and, therefore, a potential public health threat. This review simply describes the occurrence, spreading and public health significance of antimicrobial resistance in Campylobacter and E. coli.

Prevalence and Antibiotic Resistance of Campylobacter spp. in Urban and Rural Black-Headed Gulls Chroicocephalus ridibundus

We investigate the role of black-headed gulls (Chroicocephalus ridibundus), an omnivorous species that is among the most likely wild bird candidates for transmission of zoonotic agents, as a potential reservoir of Campylobacter spp. Colonies with different anthropogenic pressures were studied to examine differences in exposure to sources of Campylobacter between rural and urban birds. We recorded Campylobacter spp. in 4.87% of adult black-headed gulls and 2.22% of their chicks after analysing 1036 cloacal swabs collected over two breeding seasons in three colonies in northern Poland. Campylobacter jejuni was found most frequently (85.72%), and Campylobacter lari and Campylobacter coli were much scarcer. Prevalence of Campylobacter did not differ significantly between black-headed gulls breeding in urban (4.27%) and rural (3.80%) habitats. Almost all isolates from chicks and adults were susceptible to azithromycin (97.62%) and erythromycin (95.24%), but fewer to tetracycline (50.00%) and ciprofloxacin (47.62%). Campylobacter prevalence was unrelated to the date of sampling. Our study indicates that black-headed gulls are carriers of resistant to antibiotics Campylobacter and they can contaminate natural waterbodies with their faeces, which poses a threat to human and farm animal health.

Comprehensive characterization reveals antimicrobial-resistant and potentially virulent Campylobacter isolates from poultry meat products in Southern Brazil

The aim of this study was to perform a comprehensive characterization of 48 Campylobacter isolates obtained from broiler meat products in Southern Brazil, which had been previously typed by pulsed-field gel electrophoresis (PFGE). The antimicrobial resistance (AMR) profile and the presence of 30 virulence-associated genes (VAGs) were investigated. Six AMR patterns and 26 VAG patterns were found, indicating a great genetic diversity among the isolates. It is noteworthy that 79.2% of Campylobacter isolates were resistant to one or more antimicrobial agents, and MDR was found in 35.4%, being more prevalent in C. jejuni isolates. Data analysis for the combination of AMR and VAG profiles indicated that the antimicrobial resistance and virulence profile were not related to a particular species. The combination of the PFGE, AMR and VAG sets of data improved the discrimination power. In addition, the presence of antimicrobial-resistant Campylobacter isolates carrying virulence genes such as hcp (T6SS marker), cgtB and wlaN (LOS biosynthesis markers), among others, represents a potential emerging threat to public health. The findings also demonstrate the need for more rigorous control measures for Campylobacter in the Brazilian poultry production chain to avoid the dissemination of antimicrobial resistant and virulent Campylobacter isolates through the poultry meat.