Higher resistance of Campylobacter coli compared to Campylobacter jejuni at chicken slaughterhouse

Occurrence of Campylobacter, Listeria monocytogenes, and extended-spectrum beta-lactamase Escherichia coli in slaughterhouses before and after cleaning and disinfection

To prevent foodborne illness, adequate cleaning and disinfection (C&D) is essential to remove pathogenic bacteria from the slaughter environment. The aim of this study was to determine the presence of Campylobacter spp., Listeria monocytogenes, and extended-spectrum beta-lactamase-producing Escherichia coli (ESBL E. coli) before and after C&D in slaughterhouses. Samples from food- and non-food contact surfaces taken before and after C&D in one red meat and one poultry slaughterhouse were analyzed for the target bacteria. Whole-genome sequencing and antimicrobial susceptibility testing were performed. In total, 484 samples were analyzed. Campylobacter spp. were isolated from 13.0% to 15.5% of samples before C&D in the red meat and poultry slaughterhouse, respectively. Listeria monocytogenes was isolated before C&D in 12.5% and 5.2% of samples in the red meat and poultry slaughterhouse, respectively. It was noted that C. jejuni was detected on multiple surfaces and that L. monocytogenes showed potential persistence in one slaughterhouse. After C&D, L. monocytogenes was found in one sample. ESBL E. coli was not detected either before or after C&D. These findings show the possibility to remove pathogenic bacteria from slaughter and meat processing facilities, but also indicate that deficiencies in slaughter hygiene pose a risk of cross-contamination of meat.

A Decade of Antimicrobial Resistance in Human and Animal Campylobacter spp. Isolates

Objectives: Campylobacter spp. remain a leading cause of bacterial gastroenteritis worldwide, with resistance to antibiotics posing significant challenges to treatment and public health. This study examines profiles in antimicrobial resistance (AMR) for Campylobacter isolates from human and animal sources over the past decade. Methods: We conducted a comprehensive review of resistance data from studies spanning ten years, analyzing profiles in resistance to key antibiotics, ciprofloxacin (CIP), tetracycline (TET), erythromycin (ERY), chloramphenicol (CHL), and gentamicin (GEN). Data were collated from various regions to assess global and regional patterns of resistance. Results: The analysis reveals a concerning trend of increasing resistance patterns, particularly to CIP and TET, across multiple regions. While resistance to CHL and GEN remains relatively low, the high prevalence of CIP resistance has significantly compromised treatment options for campylobacteriosis. Discrepancies in resistance patterns were observed between human and animal isolates, with variations across different continents and countries. Notably, resistance to ERY and CHL showed regional variability, reflecting potential differences in antimicrobial usage and management practices. Conclusions: The findings underscore the ongoing challenge of AMR in Campylobacter, highlighting the need for continued surveillance and research. The rising resistance prevalence, coupled with discrepancies in resistance patterns between human and animal isolates, emphasize the importance of a One Health approach to address AMR. Enhanced monitoring, novel treatment strategies, and global cooperation are crucial for mitigating the impact of resistance and ensuring the effective management of Campylobacter-related infections.

EFSA Panel on Biological Hazards (BIOHAZ), Koutsoumanis K, Allende A, Bolton D, Bover‐Cid S, Chemaly M, De Cesare A, Herman L, Hilbert F, Lindqvist R, Nauta M, Nonno R, Peixe L, Ru G, Simmons M, Skandamis P, Suffredini E, Fox E, Gosling R(B, Gil BM, Møretrø T, Stessl B, da Silva Felício MT, Messens W, Simon AC, Alvarez‐Ordóñez A. Persistence of microbiological hazards in food and feed production and processing environments

Listeria monocytogenes (in the meat, fish and seafood, dairy and fruit and vegetable sectors), Salmonella enterica (in the feed, meat, egg and low moisture food sectors) and Cronobacter sakazakii (in the low moisture food sector) were identified as the bacterial food safety hazards most relevant to public health that are associated with persistence in the food and feed processing environment (FFPE). There is a wide range of subtypes of these hazards involved in persistence in the FFPE. While some specific subtypes are more commonly reported as persistent, it is currently not possible to identify universal markers (i.e. genetic determinants) for this trait. Common risk factors for persistence in the FFPE are inadequate zoning and hygiene barriers; lack of hygienic design of equipment and machines; and inadequate cleaning and disinfection. A well-designed environmental sampling and testing programme is the most effective strategy to identify contamination sources and detect potentially persistent hazards. The establishment of hygienic barriers and measures within the food safety management system, during implementation of hazard analysis and critical control points, is key to prevent and/or control bacterial persistence in the FFPE. Once persistence is suspected in a plant, a 'seek-and-destroy' approach is frequently recommended, including intensified monitoring, the introduction of control measures and the continuation of the intensified monitoring. Successful actions triggered by persistence of L. monocytogenes are described, as well as interventions with direct bactericidal activity. These interventions could be efficient if properly validated, correctly applied and verified under industrial conditions. Perspectives are provided for performing a risk assessment for relevant combinations of hazard and food sector to assess the relative public health risk that can be associated with persistence, based on bottom-up and top-down approaches. Knowledge gaps related to bacterial food safety hazards associated with persistence in the FFPE and priorities for future research are provided.

Identification of genes associated with environmental persistence in Campylobacter jejuni and Campylobacter coli isolates from processing in a broiler abattoir

The aim of this study was to determine the prevalence of the htrA, htrB and ppk1 genes -all of which are related to environmental persistence- in C. jejuni and C. coli isolates obtained from abattoir samples at the arrival of broilers (initial stage) and in meat products after processing (final stage). A total of 119 DNA extracts (55 C. jejuni and 64 C. coli) were included in the study. Identification of genes was performed by conventional PCR (one for each gene). The overall prevalence was 40.3%, 93.3% and 68.9% for the htrA, htrB and ppk1 genes, respectively. Statistically significant differences were found (p < 0.05) between prevalence of C. jejuni and C. coli for all three genes. In C. coli the prevalence was significantly higher for the htrA (p = 0.007) and htrB (p = 0.015) genes, while ppk1 gene prevalence was significantly higher in C. jejuni (p < 0.001). In addition, statistically significant increase in the frequency of htrA (p = 0.007) and htrB (p = 0.013) genes in the final product compared to broilers on arrival at the abattoir was observed in C. jejuni, but not in C. coli. These results suggest that htrA and htrB genes are involved in environmental persistence of Campylobacter jejuni.

Antibiotic-resistant Campylobacter coli and Campylobacter jejuni in commercial and smallholder farm animals in the Asante Akim North Municipality of Ghana

Worldwide, farm animals, in particular poultry, are an important reservoir for Campylobacter spp. However, information on Campylobacter colonization in farm animals in Africa is scarce. Hence, this cross-sectional study determined antibiotic-resistant Campylobacter from both commercial and smallholder farm animals in the Asante Akim North Municipality of Ghana. Fecal samples from poultry and livestock kept by commercial and smallholder farms were collected and analyzed using standard microbiological methods. The overall Campylobacter frequency was 20.3% (n/N = 322/1,585), and frequencies detected were similarly high in isolates from commercial (21.0%, n/N = 169/805) and smallholder (19.6%, n/N = 153/780) farms. Species isolated were C. coli (67.7%, n/N = 218/322) and C. jejuni (32.3%, n/N = 104/322). However, the frequency of C. coli was 2.1 (95% CI: 1.8-2.5) times higher than what was found for C. jejuni. Campylobacter frequencies in the rainy season was 22.2% (n/N = 258/1,160) and 15.1% (n/N = 64/425) in the dry season (prevalence ratio = 1.48, 95% CI: 1.2-1.9). About 1.7% (n/N = 6/322) of the Campylobacter isolates, all from smallholder farms, were susceptible to all antibiotics tested. Multidrug resistance was observed for 4.7% (n/N = 15/322) of the Campylobacter isolates, of which 93.3% (n/N = 14/15) occurred in isolates from commercial farms. This study highlights the need for the implementation of control programs, in commercial farming but also at the smallholder farm level, to formulate clear guidelines aimed at decreasing Campylobacter contamination of meat products and reducing the use of antibiotics in the farming sector.

Antibiotic Resistance in Campylobacter spp. Isolated from Broiler Chicken Meat and Human Patients in Estonia

Poultry meat is considered the most important source of Campylobacter spp. Because of rising antimicrobial resistance in Campylobacter spp., this study investigated the antimicrobial resistance of Campylobacter isolates from fresh broiler chicken meat originating from the Baltic countries sold in Estonian retail settings. Additionally, human clinical isolates obtained from patients with Campylobacter enteritis in Estonia were analysed. The aim of this study was to investigate the susceptibility of Campylobacter spp. to nalidixic acid, ciprofloxacin, tetracycline, streptomycin, erythromycin and gentamicin. The broth microdilution method with the EUCAMP2 panel was used for MIC determination and antimicrobial mechanisms were analysed using WGS data. A total of 46 Campylobacter strains were analysed, of which 26 (42.6%) originated from Lithuanian, 16 (26.2%) from Latvian, and 4 (6.6%) from Estonian fresh broiler chicken meat. In addition, 15 (24.6%) Campylobacter strains of patients with campylobacteriosis were tested. The antimicrobial resistance patterns of Campylobacter spp. isolated from fresh broiler chicken meat samples of Estonian, Latvian and Lithuanian origin collected in Estonian retail, and from patients with Campylobacter enteric infections, were determined. A total of 46 (75%) of the isolates tested were C. jejuni and 15 (25%) were C. coli. Campylobacter resistance was highest to nalidixic acid (90.2% of strains) and ciprofloxacin (90.2%), followed by tetracycline (57.4%), streptomycin (42.6%) and erythromycin (6.6%). All strains were sensitive to gentamicin. Additionally, antimicrobial resistance genes and point mutations were detected in 27 C. jejuni and 8 C. coli isolates previously assigned as resistant with the phenotypic method. A high antibiotic resistance of Campylobacter spp. in Lithuanian- and Latvian-origin broiler chicken meat and Estonian clinical isolates was found. Similar antibiotic resistance patterns were found for broiler chicken meat and human Campylobacter isolates.

Antimicrobial Resistance and Genetic Diversity of Campylobacter spp. Isolated from Broiler Chicken at Three Levels of the Poultry Production Chain in Costa Rica

ABSTRACT

Campylobacter spp. are considered the most common bacterial cause of human gastroenteritis, one of the four main causes of diarrheal disease worldwide, and they are one of the main foodborne pathogens causing hospitalizations and deaths. Here, 148 strains of Campylobacter spp. isolated from poultry at farms, processing plants, and retail stores in Costa Rica were examined for resistance to six antibiotics. An agar dilution test was used to determine the MIC and susceptibility profiles against doxycycline, ciprofloxacin, nalidixic acid, enrofloxacin, chloramphenicol, and erythromycin. In addition, a pulsed-field gel electrophoresis analysis was carried out to determine the genotype relatedness of a representative subset of the isolates. Approximately 136 (92%) of the 148 analyzed isolates showed resistance to the tested drugs. Nalidixic acid, ciprofloxacin, and enrofloxacin were the antibiotics for which resistance occurred most frequently (91.2, 85.8, and 85.8%, respectively), followed by doxycycline (25.0%), chloramphenicol (5.4%), and erythromycin (2.7%). The profile conferring only resistance to quinolones was the most frequently found, and only 2.0% of the isolates showed resistance to quinolones and macrolides simultaneously. Results showed a high frequency of resistant Campylobacter spp. strains and evidenced the distribution, selection, and circulation of resistant strains along the poultry chain from farms to consumers. Cross-contamination and resistance seem to play important roles in the dissemination of these strains at specific points of the poultry chain, even when control measures are being taken. The establishment of effective surveillance and control strategies represents an essential tool for foodborne diseases mitigation. The rational use of antibiotics, especially those still showing efficacy, should be a priority in both human and veterinary medicine to contain the progress of this phenomenon and its consequences.

HIGHLIGHTS

Detection of Campylobacter jejuni and Salmonella typhimurium in chicken using PCR for virulence factor hipO and invA genes (Saudi Arabia)

Campylobacter jejuni and Salmonella typhimurium are the leading causes of bacterial food contamination in chicken carcasses. Contamination is particularly associated with the slaughtering process. The present study isolated C. jejuni and S. typhimurim from fifty chicken carcass samples, all of which were acquired from different companies in Riyadh, Saudi Arabia. The identification of C. jejuni was performed phenotypically by using a hippurate test and genetically using a polymerase chain reaction with primers for 16S rRNA and hippurate hydrolase (hipO gene). For the dentification of S. typhimurim, a serological Widal test was carried out using serum anti-S. typhimurium antibodies. Strains were genetically detected using invA gene primers. The positive isolates for C. jejuni showed a specific molecular size of 1448 bp for 16S rRNA and 1148 bp for hipO genes. However, the positive isolates of the invA gene exhibited a specific molecular size at 244 bp using polymerase chain reaction (PCR). Comparing sequencing was performed with respect to the invA gene and the BLAST nucleotide isolates that were identified as Salmonella enterica subsp. enterica serovar typhimurium strain ST45, thereby producing a similarity of 100%. The testing identified C.jejuni for hippuricase, GenBank: Z36940.1. While many isolates of Salmonella spp. that contained the invA gene were not necessarily identified as S. typhimurim, the limiting factor for the Widal test used antiS. typhimurum antibodies. The multidrug resistance (MDR) of C. jejuni isolates in chickens was compared with the standard C. jejuni strain ATCC 22931. Similarly, S. typhimurium isolates were compared with the standard S. typhimurium strain ATCC 14028.

Hyper-Aerotolerant Campylobacter coli From Swine May Pose a Potential Threat to Public Health Based on Its Quinolone Resistance, Virulence Potential, and Genetic Relatedness

Campylobacter, a major foodborne pathogen, is susceptible to oxygen. Recently, aerotolerant Campylobacter with enhanced tolerance to aerobic stress has become a major concern in food safety. However, the aerotolerance of Campylobacter coli from pigs has not been studied extensively. Here, we sought to investigate the prevalence of C. coli across multiple swine groups in farms, including weaning, growing, and fattening pigs in production stages and pregnant sows. Additionally, we analyzed C. coli aerotolerance, quinolone resistance, virulence potential, and multilocus sequence typing (MLST) genotypes. Finally, we compared the characteristics of C. coli according to the aerotolerance levels. In total, we obtained 124 (66.3%) C. coli isolates from 187 swine fecal samples across six swine farms. The pathogen was prevalent in weaning (45.5%), growing (68.3%), and fattening (75.4%) pigs, and pregnant sows (66.7%). Hyper-aerotolerant HAT C. coli (13.7% of 124 isolates) was present in all swine groups, with the highest proportion in the pregnant sows (27.3%). All HAT isolates possessed diverse virulence-related genes such as flaA, cadF, pldA, ceuE, and cdtA. All C. coli isolates were resistant to quinolones, and 12 (10%) presented high-level ciprofloxacin resistance (MIC ≥ 32 μg/mL). The proportion of C. coli isolates with a high-level ciprofloxacin resistance was the highest in HAT C. coli (18.8%). Furthermore, six MLST sequence types (STs) (ST827, ST830, ST854, ST1016, ST1068, and ST1096) of swine-derived C. coli were in common with human-derived C. coli (PubMLST). The proportion of C. coli belonging to such shared STs at each aerotolerance level was the highest in HAT C. coli (HAT vs. oxygen-sensitive; OR = 3.13). In conclusion, quinolone resistance of C. coli may be distributed throughout in all swine groups in farms. HAT C. coli is likely to remain in pig farms and re-infect other pigs in the farms. Furthermore, swine-derived HAT C. coli could be transmitted to humans easily through the food chain owing to its aerotolerance, and it could pose a threat to public health owing to its high-level ciprofloxacin resistance and virulence. This study highlights the need to develop management practices that prevent the transmission of swine-derived HAT C. coli to humans.

Method-Related Impacts on Campylobacter coli Recovery From Sampling Materials And Meat

A defined Campylobacter coli (C. coli) suspension was inoculated on sterile sampling materials (cotton bud, polyester bud, cellulose sponge) and pieces of lamb meat. Various combinations of diluents (phosphate buffer saline ± Tween®80) and sampling methods (direct homogenization, simulating the excision method for meat, and swabbing) were investigated for the recovery (detachment) of C. coli cells from the inoculated samples. The obtained C. coli bacteria, as quantified by real-time PCR with respect to the dilution factors and the initial inoculum, were used for the calculation of the recovery (%) per sampling material and method. Regarding artificially inoculated sampling materials, the lowest recovery was observed for cotton buds (2.8%) and the highest for cellulose sponge (28.9%), and the differences between the obtained results were statistically significant (P < 0.05). As regards lamb meat, the lowest recovery was observed for swabbing with cotton buds (3.2%) and the highest for direct homogenization (10.7%). The results indicate an overall low rate of bacterial recovery from contaminated samples, with cellulose sponges and polyester buds being significantly superior to cotton buds, and direct homogenization of meat with diluent better than swabbing. The type of sampling materials and methods applied for the quantification of C. coli entails a key impact on determining the actual contamination of the examined samples.

Comparison of Campylobacter jejuni Slaughterhouse and Surface-Water Isolates Indicates Better Adaptation of Slaughterhouse Isolates to the Chicken Host Environment

Campylobacter jejuni is an emerging food-borne pathogen that poses a high risk to human health. Knowledge of the strain source can contribute significantly to an understanding of this pathogen, and can lead to improved control measures in the food-processing industry. In this study, slaughterhouse and surface-water isolates of C. jejuni were characterized and compared in terms of their antimicrobial resistance profiles and adhesion to stainless steel and chicken skin. Resistance of C. jejuni biofilm cells to benzalkonium chloride and Satureja montana ethanolic extract was also tested. The data show that the slaughterhouse isolates are more resistant to ciprofloxacin, and adhere better to stainless steel at 42 °C, and at 37 °C in 50% chicken juice. Additionally, biofilm cells of the isolate with the greatest adhesion potential (C. jejuni S6) were harvested and tested for resistance to S. montana ethanolic extract, benzalkonium chloride, and erythromycin; and for efflux-pump activity, as compared to their planktonic cells. The biofilm cells showed increased resistance to both S. montana ethanolic extract and erythromycin, and increased efflux-pump activity. These data indicate adaptation of C. jejuni slaughterhouse isolates to the chicken host, as well as increased biofilm cell resistance due to increased efflux-pump activity.

Antimicrobial resistance of Campylobacter isolates recovered from broilers in the Republic of Ireland in 2017 and 2018: an update

1. Campylobacteriosis is the leading cause of human bacterial gastroenteritis. Broilers are considered the most important source of human Campylobacter infection. In the 2008 European baseline survey Ireland had a 98% prevalence of campylobacter-contaminated broiler carcases. 2. Randomly-selected Campylobacter isolates (296 C. jejuni, 54 C. coli) recovered in 2017 and 2018, from Irish broiler neck skin and caeca were tested for their resistance to tetracycline, erythromycin, gentamicin, ciprofloxacin, nalidixic acid and streptomycin. 3. Overall, 45% of the Campylobacter spp. isolates tested were resistant to at least one antimicrobial. Tetracycline resistance (38%) was most prevalent in C. jejuni, followed by ciprofloxacin and nalidixic acid resistance (29%). In C. coli, resistance to ciprofloxacin and nalidixic acid (26%) was most prevalent followed by resistance to tetracycline (13%). Gentamicin resistance was undetected and resistance to streptomycin was low for C. jejuni (1%) and C. coli (4%). All C. jejuni isolates examined were erythromycin-sensitive, while 9% of C. coli isolates were erythromycin-resistant. Three multidrug-resistant C. coli isolates were recovered. 4. While antibiotic resistance rates were somewhat similar to figures reported nationally over the past 20 years, the prevalence of tetracycline resistance in C. jejuni has increased. The persistence of substantial ciprofloxacin resistance in the Irish broiler population was noteworthy, despite fluoroquinolones having been banned for growth promotion in Europe since 2006.

Prevalence, genotypic diversity and detection of virulence genes in thermotolerant Campylobacter at different stages of the poultry meat supply chain

Thermotolerant Campylobacter is the leading bacterial cause of foodborne illness in humans worldwide. The objectives of this study were to estimate prevalence and to identify and characterize potential sources of thermotolerant Campylobacter contamination in broilers on farms and at the slaughterhouse; to evaluate the clonal relationship among thermotolerant Campylobacter isolates from different stages of the broiler meat supply chain, and to analyze the presence of virulence genes in different sources of thermotolerant Campylobacter. A total of 1210 samples were collected from three broiler meat supply chains in Santa Fe, Argentina. At the farms, the sampling collection included broilers one week prior to slaughter, wild-living birds, domestic dogs, wild rodents, farm workers' boots, litter, feed, drinking water, flies, and darkling beetles (Alphitobius diaperinus). At the slaughtering line, the samples taken were from the evisceration zone (broiler cecum, working surfaces, evisceration knives and workers' hands), from the chiller zone (surfaces and direct supply water) and from the packing zone (work surfaces, workers' hands and broiler carcasses). The samples taken along each supply chain were in the same batch. The isolates obtained were identified to the species level (C. jejuni and C. coli) by multiplex PCR and were analyzed using pulsed-field gel electrophoresis to compare different profiles according to the source. Finally, the presence of 11 virulence genes was examined (cadF, cdtA, cdtB, cdtC, ciaB, flaA, flhA, iam, wlaN, virB11, racR). From 254 isolates, 128 (50.4%) were Campylobacter jejuni and 126 (49.6%) Campylobacter coli. C. jejuni was the species most prevalent in farm and C. coli the species most prevalent at the slaughterhouse. We detected thermotolerant Campylobacter in samples of wild birds, darkling beetles, farm workers' boots, flies and litter. At the slaughterhouse, the prevalence varied along the process line. By analyzing PFGE results, C. jejuni showed 21 profiles with three predominant genotypes, while C. coli showed 14 profiles with four predominant genotypes. A high genotype diversity was found; however, relationships between isolates from different stages of the broiler meat chain, between broiler and potential sources of thermotolerant Campylobacter contamination and between strains in the farm and in the slaughterhouse were detected. Furthermore, there was evidence of cross-contamination at the slaughterhouse. FlaA, flhA genes were detected in all strains, and the third most prevalent virulence gene was cadF. Only those strains obtained from flies, wild-living birds and broiler carcass samples harbored 10 of 11 pathogenic genes. The prevalence of some pathogenic genes between C. jejuni and C. coli was different. This evidence should contribute the scientific basis to implement risk management measures in public health.

Viability Quantitative PCR Utilizing Propidium Monoazide, Spheroplast Formation, and Campylobacter coli as a Bacterial Model

A viability quantitative PCR (qPCR) utilizing propidium monoazide (PMA) is presented for rapid quantification of viable cells using the foodborne pathogen Campylobacter coli as a bacterial model. It includes optimized spheroplast formation via lysozyme and EDTA, induction of a mild osmotic shock for enhancing the selective penetration of PMA into dead cells, and exploitation of an internal sample process control (ISPC) involving cell inactivation to assess residual false-positive signals within each sample. Spheroplasting of bacteria in exponential phase did not permit PMA entrance into viable cells since a strong linear relationship was detected between simple qPCR and PMA-qPCR quantification, and no differences were observed regardless of whether spheroplasting was utilized. The PMA-qPCR signal suppression of dead cells was elevated using spheroplast formation. With regard to the ISPC, cell inactivation by hydrogen peroxide resulted in higher signal suppression during qPCR than heat inactivation did. Viability quantification of C. coli cells by optimized spheroplasting-PMA-qPCR with ISPC was successfully applied in an aging pure culture under aerobic conditions and artificially inoculated meat. The same method exhibited a high linear range of quantification (1.5 to 8.5 log10 viable cells ml-1), and results were highly correlated with culture-based enumeration. PMA-qPCR quantification of viable cells can be affected by their rigidity, age, culture media, and niches, but spheroplast formation along with osmotic shock and the use of a proper ISPC can address such variations. The developed methodology could detect cells in a viable-but-nonculturable state and might be utilized for the quantification of other Gram-negative bacteria.IMPORTANCE There is need for rapid and accurate methods to detect viable bacterial cells of foodborne pathogens. Conventional culture-based methods are time-consuming and unable to detect bacteria in a viable-but-nonculturable state. The high sensitivity and specificity of the quantitative PCR (qPCR) are negated by its inability to differentiate the DNAs from viable and dead cells. The combination of propidium monoazide (PMA), a DNA-intercalating dye, with qPCR assays is promising for detection of viable cells. Despite encouraging results, these assays still encounter various challenges, such as false-positive signals by dead cells and the lack of an internal control identifying these signals per sample. The significance of our research lies in enhancing the selective entrance of PMA into dead Campylobacter coli cells via spheroplasting and in developing an internal sample process control, thus delivering reliable results in pure cultures and meat samples, approaches that can be applicable to other Gram-negative pathogens.

A One Health approach to prevention, treatment, and control of campylobacteriosis

PURPOSE OF REVIEW

To review recent findings regarding the control and treatment of campylobacteriosis.

RECENT FINDINGS

The application of improved diagnostics has led to an upward shift in the attributable burden of Campylobacter infections, in both the United States and Europe as well as in resource-poor settings. Increased focus has brought a fundamental feature of campylobacteriosis -- the ability to cause relapsing disease back into focus, and expanding data on antimicrobial resistance has lead from a switch in first-line therapy for severe diarrhea from quinolones to azithromycin in most contexts, even as evidence of expanding macrolide resistance emerges.

SUMMARY

Campylobacter spp. infection is a common infection worldwide. Antibiotic-resistant Campylobacter spp. has become an emerging threat with the increase in industrial poultry production, as well as the broad use of antibiotics in both animals and humans.

Molecular epidemiology of Campylobacter isolates from broiler slaughterhouses in Tripoli, North of Lebanon

1. The real burden of Campylobacter spp. in Lebanon is still unknown. The aims of this study were to unravel the epidemiology of Campylobacter spp. in broilers at slaughterhouses in Tripoli, North of Lebanon and to characterise their antibiotic resistance profiles.2. From May to November 2015, sampling was performed through five repeated surveys from 15 slaughterhouses that sold chicken directly to Lebanese customers. Isolates were subjected to pulsed field gel electrophoresis (PFGE) and flaA-restriction fragment length polymorphism (flaA-RFLP).3. All investigated slaughterhouses were found to be positive for Campylobacter spp. Campylobacter coli was the predominant species (38 isolates) followed by C. jejuni (eight isolates). A noticeable level of resistance was detected among isolates against ciprofloxacin (97% of C. coli and 87.5% of C. jejuni), amoxicillin (89% of C. coli and 75% of C. jejuni), gentamicin (79% of C. coli and 50% of C. jejuni), and co-amoxiclav (24% of C. coli and 25% of C. jejuni). Erythromycin and ertapenem resistance were observed only in C. coli with the following percentages 74% and 13% respectively, but not in C. jejuni. PFGE and flaA-RFLP using DdeI as restriction enzyme divided the strains into 27 and 25 types respectively.4. The high observed genetic diversity of Campylobacter spp. revealed the complexity of the spread of this genus in broilers. This study highlighted the pressing need to monitor antibiotic resistance and to ensure food safety from 'farm to fork' in Lebanon.

Evolution of Campylobacter jejuni of poultry origin in Brazil

Campylobacter jejuni is the most common pathogen associated with foodborne diseases. Persistent presence of this pathogen contaminating the environment in slaughterhouses and chicken products have been reported worldwide. Although many efforts have been employed for reducing C. jejuni contamination, few studies have been conducted to understand the dynamics of C. jejuni in slaughterhouses over time. In this study, we evaluated the virulence, antibiotic resistance and genetic diversity profiles of 99 C. jejuni isolated from chilled chicken carcasses collected in Brazilian slaughterhouses during two distinct periods (2011-2012 and 2015-2016). The virulence profile was evaluated for the presence of flaA, ciaB, cadF, pldA and cdtABC genes. Antibiotic resistance was evaluated for amoxicillin-clavulanic acid, gentamicin, erythromycin and tetracycline. Genetic diversity was assessed using RAPD-PCR. The prevalence of C. jejuni was significantly reduced in 2015-2016 as well the number of antibiotic (and multidrug) resistant isolates, except for tetracycline. However, isolates from 2015 to 2016 showed higher prevalence of multiple virulence genes and genetic diversity profile compared to isolates from 2011 to 2012. During the studied period, stricter regulations to control pathogens in poultry farms and slaughterhouses were implemented in Brazil, which may have contributed to the profile variation observed due to changes of selective pressures on bacterial populations.

The European Union summary report on antimicrobial resistance in zoonotic and indicator bacteria from humans, animals and food in 2017

The data on antimicrobial resistance in zoonotic and indicator bacteria in 2017, submitted by 28 EU Member States (MSs), were jointly analysed by EFSA and ECDC. Resistance in zoonotic Salmonella and Campylobacter from humans, animals and food, and resistance in indicator Escherichia coli as well as meticillin‐resistant Staphylococcus aureus in animals and food were addressed, and temporal trends assessed. ‘Microbiological’ resistance was assessed using epidemiological cut‐off (ECOFF) values; for some countries, qualitative data on human isolates were interpreted in a way which corresponds closely to the ECOFF‐defined ‘microbiological’ resistance. In Salmonella from humans, as well as in Salmonella and E. coli isolates from fattening pigs and calves of less than 1 year of age, high proportions of isolates were resistant to ampicillin, sulfonamides and tetracyclines, whereas resistance to third‐generation cephalosporins was uncommon. Varying occurrence/prevalence rates of presumptive extended‐spectrum beta‐lactamase (ESBL)/AmpC producers in Salmonella and E. coli monitored in meat (pork and beef), fattening pigs and calves, and Salmonella monitored in humans, were observed between countries. Carbapenemase‐producing E. coli were detected in one single sample from fattening pigs in one MS. Resistance to colistin was observed at low levels in Salmonella and E. coli from fattening pigs and calves and meat thereof and in Salmonella from humans. In Campylobacter from humans, high to extremely high proportions of isolates were resistant to ciprofloxacin and tetracyclines, particularly in Campylobacter coli. In five countries, high to very high proportions of C. coli from humans were resistant also to erythromycin, leaving few options for treatment of severe Campylobacter infections. High resistance to ciprofloxacin and tetracyclines was observed in C. coli isolates from fattening pigs, whereas much lower levels were recorded for erythromycin. Combined resistance to critically important antimicrobials in both human and animal isolates was generally uncommon but very high to extremely high multidrug resistance levels were observed in S. Typhimurium and its monophasic variant in both humans and animals. S. Kentucky from humans exhibited high‐level resistance to ciprofloxacin, in addition to a high prevalence of ESBL.

Antibiotic Resistance of Campylobacter Species in a Pediatric Cohort Study

The objective of this study was to determine the phenotypic patterns of antibiotic resistance and the epidemiology of drug-resistant Campylobacter spp. from a low-resource setting. A birth cohort of 303 patients was followed until 5 years of age. Stool samples from asymptomatic children (n = 10,008) and those with diarrhea (n = 3,175) were cultured for Campylobacter Disk diffusion for ciprofloxacin (CIP), nalidixic acid (NAL), erythromycin (ERY), azithromycin (AZM), tetracycline (TE), gentamicin (GM), ampicillin (AMP), amoxicillin and clavulanic acid (AMC), ceftriaxone (CRO), chloramphenicol (C), and trimethoprim-sulfamethoxazole (TMS) was determined. Antibiotic resistances in Campylobacter jejuni and non-C. jejuni isolates from surveillance and diarrhea samples were compared, and the association between personal macrolide exposure and subsequent occurrence of a macrolide-resistant Campylobacter spp. was assessed. Of 917 Campylobacter isolates, 77.4% of C. jejuni isolates and 79.8% of non-C. jejuni isolates were resistant to ciprofloxacin, while 4.9% of C. jejuni isolates and 24.8% of non-C. jejuni isolates were not susceptible to azithromycin. Of the 303 children, 33.1% had been diagnosed with a Campylobacter strain nonsusceptible to both azithromycin and ciprofloxacin. Personal macrolide exposure did not affect the risk of macrolide-resistant Campylobacter Amoxicillin and clavulanic acid (94.0%) was one of the antibiotics with the highest rates of susceptibility. There is a high incidence of quinolone- and macrolide-resistant Campylobacter infections in infants under 24 months of age. Given the lack of association between personal exposure to macrolides and a subsequent Campylobacter infection resistant to macrolides, there is a need to evaluate the source of multidrug-resistant (MDR) Campylobacter This study provides compelling evidence to propose amoxicillin/clavulanic acid as a treatment for campylobacteriosis.

The European Union summary report on antimicrobial resistance in zoonotic and indicator bacteria from humans, animals and food in 2016

The data on antimicrobial resistance in zoonotic and indicator bacteria in 2016, submitted by 28 EU Member States (MSs), were jointly analysed by the EFSA and ECDC. Resistance in bacterial isolates of zoonotic Salmonella and Campylobacter from humans, animals and food, and resistance in indicator Escherichia coli as well as in meticillin-resistant Staphylococcus aureus from animals and food were addressed. 'Microbiological' resistance was assessed using epidemiological cut-off (ECOFF) values; for some countries, qualitative data on isolates from humans were interpreted in a way that corresponds closely to ECOFF-defined 'microbiological' resistance. In Salmonella from humans, the occurrence of resistance to ampicillin, sulfonamides and tetracyclines was high, whereas resistance to third-generation cephalosporins was low. In Salmonella and E. coli isolates from broilers, fattening turkeys and their meat, resistance to ampicillin, (fluoro)quinolones, tetracyclines and sulfonamides was frequently high, whereas resistance to third-generation cephalosporins was rare. The occurrence of ESBL-/AmpC producers was low in Salmonella and E. coli from poultry and in Salmonella from humans. The prevalence of ESBL-/AmpC-producing E. coli, assessed in poultry and its meat for the first time, showed marked variations among MSs. Fourteen presumptive carbapenemase-producing E. coli were detected from broilers and its meat in two MSs. Resistance to colistin was observed at low levels in Salmonella and E. coli from poultry and meat thereof and in Salmonella from humans. In Campylobacter from humans, broilers and broiler meat, resistance to ciprofloxacin and tetracyclines was high to extremely high, whereas resistance to erythromycin was low to moderate. Combined resistance to critically important antimicrobials in isolates from both humans and animals was generally uncommon, but very high to extremely high multidrug resistance levels were observed in certain Salmonella serovars. Specific serovars of Salmonella (notably Kentucky) from both humans and animals exhibited high-level resistance to ciprofloxacin, in addition to findings of ESBL.

The European Union summary report on antimicrobial resistance in zoonotic and indicator bacteria from humans, animals and food in 2015

The data on antimicrobial resistance in zoonotic and indicator bacteria in 2015, submitted by 28 EU Member States (MSs), were jointly analysed by EFSA and ECDC. Resistance in zoonotic Salmonella and Campylobacter from humans, animals and food, and resistance in indicator Escherichia coli as well as meticillin‐resistant Staphylococcus aureus in animals and food were addressed. ‘Microbiological’ resistance was assessed using epidemiological cut‐off (ECOFF) values; for some countries, qualitative data on human isolates were interpreted in a way which corresponds closely to the ECOFF‐defined ‘microbiological’ resistance. In Salmonella from humans, high proportions of isolates were resistant to ampicillin, sulfonamides and tetracyclines, whereas resistance to third‐generation cephalosporins was low. In Salmonella and Escherichia coli isolates from fattening pigs and calves under one year of age, resistance to ampicillin, tetracyclines and sulfonamides was frequently detected, whereas resistance to third‐generation cephalosporins was uncommon. For the first time, presumptive extended‐spectrum beta‐lactamase (ESBL)‐/AmpC‐/carbapenemase‐production in Salmonella and Escherichia coli was monitored in humans (Salmonella), meat (pork and beef), fattening pigs and calves. Varying occurrence/prevalence rates of ESBL‐/AmpC‐producers were observed between countries, and carbapenemase‐producing Escherichia coli were detected in single samples of pig meat and from fattening pigs from two MSs. Resistance to colistin was observed at low levels in Salmonella and Escherichia coli from fattening pigs and calves under one year of age and meat thereof. In Campylobacter from humans, high to extremely high proportions of isolates were resistant to ciprofloxacin and tetracyclines, particularly in C. coli. In a few countries, a third to half of C. coli in humans were resistant also to erythromycin, leaving few options for treatment of severe Campylobacter infections. High resistance to ciprofloxacin and tetracyclines was observed in C. coli isolates from fattening pigs, whereas much lower levels were recorded for erythromycin. Co‐resistance to critically important antimicrobials in both human and animal isolates was generally uncommon.

Antimicrobial Resistance of Campylobacter Species Isolated from Broilers in Live Bird Markets in Shanghai, China

This study was conducted to determine the prevalence of antimicrobial resistance in Campylobacter spp. isolates from broilers in live bird markets (LBMs). A total of 209 Campylobacter spp. isolates (84 Campylobacter jejuni; 125 Campylobacter coli) were recovered from 364 broiler cecum samples collected from five LBMs in Shanghai, China. Minimum inhibitory concentrations of 13 antimicrobials were determined using agar dilution method. More than 96% of the Campylobacter spp. isolates were resistant to quinolones and tetracyclines. A high prevalence of macrolide resistance (erythromycin, 84.0%; azithromycin, 80.8%) was observed in C. coli, but not in C. jejuni (erythromycin, 6.0%; azithromycin, 2.4%). C. coli also showed significantly higher resistance than C. jejuni to clindamycin, gentamicin, and kanamycin. In contrast, C. coli isolates had lower resistance to florfenicol than the C. jejuni isolates. The majority of the C. jejuni (88.1%) and C. coli (97.6%) isolates exhibited multidrug resistance (MDR) to three or more classes of antimicrobials. All of the 208 ciprofloxacin-resistant Campylobacter spp. isolates were positive for the C257T mutation of the gyrA gene. In addition, the tet(O) gene was identified in all of the 202 doxycycline-resistant Campylobacter spp. isolates. Furthermore, 75.7% and 20.4% of the 103 azithromycin-resistant Campylobacter spp. isolates were positive for the A2075G mutation of the 23S rRNA gene and the presence of the erm(B) gene, respectively. Moreover, the cat gene was found in 14.3% (8/56) and 76.8% (73/95) of the chloramphenicol-resistant C. jejuni and C. coli isolates, respectively. To the best of our knowledge, this is the first report of the prevalence of antimicrobial resistance among Campylobacter spp. isolates originating from LBMs. The high prevalence of MDR Campylobacter spp. isolates in LBMs highlights the need to implement efficient intervention measures to control not only Campylobacter contamination in LBMs but also dissemination of antimicrobial resistance among Campylobacter spp. in poultry production.

Functional genomics in Campylobacter coli identified a novel streptomycin resistance gene located in a hypervariable genomic region

Numerous aminoglycoside resistance genes have been reported in Campylobacter spp. often resembling those from Gram-positive bacterial species and located in transferable genetic elements with other resistance genes. We discovered a new streptomycin (STR) resistance gene in Campylobactercoli showing 27-34 % amino acid identity to aminoglycoside 6-nucleotidyl-transferases described previously in Campylobacter. STR resistance was verified by gene expression and insertional inactivation. This ant-like gene differs from the previously described aminoglycoside resistance genes in Campylobacter spp. in several aspects. It does not appear to originate from Gram-positive bacteria and is located in a region corresponding to a previously described hypervariable region 14 of C. jejuni with no other known resistance genes detected in close proximity. Finally, it does not belong to a multiple drug resistance plasmid or transposon. This novel ant-like gene appears widely spread among C. coli as it is found in strains originating both from Europe and the United States and from several, apparently unrelated, hosts and environmental sources. The closest homologue (60 % amino acid identity) was found in certain C. jejuni and C. coli strains in a similar genomic location, but an association with STR resistance was not detected. Based on the findings presented here, we hypothesize that Campylobacter ant-like gene A has originated from a common ancestral proto-resistance element in Campylobacter spp., possibly encoding a protein with a different function. In conclusion, whole genome sequencing allowed us to fill in a knowledge gap concerning STR resistance in C. coli by revealing a novel STR resistance gene possibly inherent to Campylobacter.