Colony multiplex PCR assay for identification and differentiation of Campylobacter jejuni, C. coli, C. lari, C. upsaliensis, and C. fetus subsp. fetus

Investigation of Aliarcobacter spp. and Campylobacter spp. in uterine contents of cows: Antibacterial susceptibility and phylogenetic analysis of the isolates

The study aimed to isolate and identify Aliarcobacter spp. and Campylobacter spp. from the uterine contents of cows and to determine the susceptibilities of the isolates to various antibiotics. For this purpose, a total of 63 cows (with repeat breeder, metritis, and healthy) uterine contents were collected from a slaughterhouse. Pre-enrichment and membrane filtration methods were used to isolate Aliarcobacter and Campylobacter spp., and phenotypic and molecular methods were used to identify the isolates. Antibacterial susceptibilities of the isolates were determined by the disc diffusion method. A total of 11 (17.46 %, 11/63) samples were found positive for both genera, and 12 isolates were obtained from these samples. Out of 9 Campylobacter isolates, 5, 3, and 1 were identified as C. jejuni, C. sputorum, and C. hyointestinalis, respectively. Also, two and one of Aliarcobacter spp. isolates were identified as Aliarcobacter sp. and A. butzleri, respectively. All isolates of both genera were found to be sensitive to amoxicillin-clavulanic acid, ampicillin, erythromycin, and enrofloxacin and resistant to trimethoprim + sulfamethoxazole. This is the first study that reported on the isolation of C. hyointestinalis from cattle uterine contents. It was concluded that Campylobacter and Aliarcobacter species should be considered among the most important etiological agents in uterine infections that cause infertility in cows. The isolation of Aliarcobacter and Campylobacter spp. from healthy cow uteri within the scope of this study suggests the possibility that these agents could colonize the uterus, similar to the colonization observed in the intestine and gallbladder.

Exploring the Prevalence and Resistance of Campylobacter in Urban Bird Populations

The increasing urbanization of ecosystems has had a significant impact on wildlife over the last few years. Species that find an unlimited supply of food and shelter in urban areas have thrived under human presence. Wild birds have been identified as amplifying hosts and reservoirs of Campylobacter worldwide, but the information about its transmission and epidemiology is still limited. This study assessed the prevalence of Campylobacter in 137 urban birds admitted at a wildlife rescue center, with 18.8% of individuals showing positive. C. jejuni was the most frequent species (82.6%), followed by C. coli and C. lari (4.3% each). The order Passeriformes (33.3%) showed significant higher presence of Campylobacter when compared to orders Columbiformes (0%) and Ciconiiformes (17.6%), as well as in samples collected during the summer season (31.9%), from omnivorous species (36.8%) and young individuals (26.8%). Globally, Campylobacter displayed a remarkable resistance to ciprofloxacin (70.6%), tetracycline (64.7%), and nalidixic acid (52.9%). In contrast, resistance to streptomycin was low (5.8%), and all the isolates showed susceptibility to erythromycin and gentamycin. The results underline the importance of urban birds as reservoirs of thermophilic antimicrobial-resistant Campylobacter and contribute to enhancing the knowledge of its distribution in urban and peri-urban ecosystems.

The characterization and correlation between the phenotypic and genotypic resistance of Campylobacter spp. isolates from commercial broilers and native chickens in the south of Thailand

RESEARCH HIGHLIGHTS

High Campylobacter prevalence in chickens; C. jejuni more prevalent than C. coli.Susceptibility to macrolides but resistance to quinolones/tetracyclines in isolates.Homogeneous resistance patterns within farms; higher in broilers than in native birds.Partial association between phenotypic and genotypic resistance among isolates.

Impact of In-Feed versus In-Water Chlortetracycline and Tiamulin Administrations on Fecal Prevalence and Antimicrobial Susceptibilities of Campylobacter in a Population of Nursery Pigs

Antimicrobial resistance (AMR) in bacteria is a major public health concern in the US and around the world. Campylobacter is an important foodborne pathogen that resides in the gut of pigs and is shed in feces, with the potential to be transmitted to humans. In pigs, the oral route, either in-feed or in-water, is by far the most common route of administration of antimicrobials. Because the distribution of the antibiotic in the gut and the dosages are different, the impact of in-feed vs. in-water administration of antibiotics on the development of AMR is likely to be different. Therefore, a study was conducted to compare in-feed vs. in-water administrations of chlortetracycline (CTC) and/or tiamulin on fecal prevalence and AMR profiles of Campylobacter among weaned nursery piglets. A total of 1,296 weaned piglets, allocated into 48 pens (27 piglets per pen), were assigned randomly to six treatment groups: Control (no antibiotic), in-feed CTC, in-water CTC, in-feed tiamulin, in-water tiamulin, or in-feed CTC and tiamulin. Fecal samples were collected randomly from 5 piglets from each pen during the pre-treatment (days 0, 7), treatment (days 14, 21), and post-treatment (days 28, 35) phases. Bacterial isolations and species identifications were conducted by culture and PCR, respectively. The microbroth dilution method with SensititreTM plates was used to determine the antimicrobial susceptibility and resistance of Campylobacter isolates. The results on resistance were interpreted based on the European Committee on Antimicrobial Susceptibility Testing (EUCAST) epidemiological cutoff values for Campylobacter. The overall prevalence of Campylobacter was 18.2% (262/1440). Speciation of Campylobacter isolates by PCR indicated the prevalence of only two species: Campylobacter hyointestinalis (17.9%; 258/1440) and C. coli (0.3%; 4/1440). Campylobacter isolates were resistant to tetracycline (98.5%), ciprofloxacin (89.3%), and nalidixic acid (60.3%). Neither the antibiotic nor the route of administration had an effect (p > 0.05) on the prevalence of AMR Campylobacter in the feces of piglets.

Genotyping and antibiotic susceptibility of Campylobacter species isolated from raw milk samples in Qazvin, Iran

OBJECTIVE

Campylobacter species are major causes of foodborne illnesses, with unpasteurized milk being a significant carrier of these bacteria, posing a public health risk. One of the challenges in managing Campylobacter infections is the emergence and spread of antibiotic resistance. We conducted a study in Qazvin, Iran, testing 84 raw cow's milk samples to determine the frequency of C. jejuni and C. coli using culture-based and multiplex PCR methods. Additionally, the disk diffusion and RAPD-PCR approaches were utilized to evaluate the phenotypic antibiotic resistance profile and genetic diversity of Campylobacter strains.

RESULTS

The findings indicated that Campylobacter spp. was present in 19.05% of the samples, with C. coli being the predominant isolate. We tested eight antibiotic agents, and the resistance levels of the isolates were as follows: erythromycin 100%, tetracycline 75%, doxycycline 56.25%, ceftriaxone 43.75%, chloramphenicol 37.5%, amoxicillin-clavulanic acid 25%, nalidixic acid 12.5%, and azithromycin 6.25%. Genetic diversity analysis categorized Campylobacter isolates into 39 clusters, indicating a wide diversity among strains. However, no significant correlation was observed between antibiotic resistance and cluster patterns. These findings underscore the role of raw milk as a reservoir for Campylobacter spp. and highlight the substantial antibiotic resistance and genetic diversity within the species population.

First report of phenotypic and genotypic (blaOXA-61) beta-lactam resistance in Campylobacter jejuni from broilers in Indonesia

Background and Aim

Campylobacter is a zoonotic bacterium that is a major source of foodborne diseases. In humans, most cases of campylobacteriosis are caused by Campylobacter jejuni. Poultry is the main reservoir of Campylobacter for humans, because Campylobacter is part of the normal flora of the digestive tract of poultry. Antimicrobial resistance to several antibiotics in Campylobacter isolated from humans and food animals has increased rapidly. Beta-lactam is an antibiotic with a high prevalence of resistance in Campylobacter. This study aimed to investigate phenotypic and genotypic (blaOXA-61) beta-lactam resistance in C. jejuni from broilers in Indonesia.

Materials and Methods

A total of 100 samples of broiler intestinal contents were obtained from 10 broiler farms in Pasuruan Regency, Indonesia. Campylobacter jejuni was identified using conventional and polymerase chain reaction (PCR)-based methods. Phenotypic detection of beta-lactam resistance was performed using an antimicrobial susceptibility test with antibiotic disks of aztreonam, ampicillin, and amoxicillin-clavulanic acid. Genotypic detection by PCR was performed using the blaOXA-61 gene, which encodes beta-lactamase.

Results

Campylobacter jejuni was identified in 23% of the samples. Phenotypically, 100% (23/23) and 73.9% (17/23) C. jejuni isolates had high resistance to aztreonam and ampicillin, respectively, but all isolates were susceptible to amoxicillin-clavulanic acid. Genotypically, all isolates carried blaOXA-61, indicated by the presence of a 372-bp PCR product.

Conclusion

Campylobacter jejuni is highly resistant to beta-lactams and is a serious threat to human health. Resistance to beta-lactams should be monitored because beta-lactamase genes can be transferred between bacteria. Public awareness must also be increased on the importance of using antibiotics rationally in humans and animals.

Campylobacter jejuni and Campylobacter coli in human stool samples: antibiotic resistance profiles, putative virulence determinants and molecular characterization of the isolates

Campylobacters, especially C. jejuni and C. coli, have become one of the leading causes of acute gastroenteritis in humans worldwide in recent years. We aimed to investigate the presence, antimicrobial resistance, putative virulence genes, and molecular characterization of C. jejuni and C. coli recovered from human acute gastroenteritis cases in the study. In the study, suspected Campylobacter spp. isolates were obtained in 43 (5%) feces samples collected from a total of 850 patients who applied to the Erciyes University Medical Faculty acute clinic between March 2019 and February 2020. As a result of the phenotypic tests, these isolates were determined to be Campylobacter spp. According to the multiplex PCR, 33 of 43 Campylobacter spp. isolates were identified as C. jejuni (76%) and ten isolates were as C. coli (24%). In the disc diffusion test, the highest resistance rate was found in the trimethoprim/sulfamethoxazole (90.1%) and ciprofloxacin (90.1%), and the lowest rate was found in the amoxicillin-clavulanic acid (9.3%). In Campylobacter spp. isolates, the virulence genes cdtA, virB11, cdtB, cadF, iam, ceu, and flaA were found to be positive at rates of 26 (60%), 28 (65.6%), 13 (30%), 4 (9%), 27 (62%), 17 (39%), and 7 (16%), respectively. However, the cdtC gene was not detected in any of the isolates. The study searched tetO gene to examine the genetic aspect of tetracycline resistance, which was found in all Campylobacter spp. isolates. In the PCR reactions to investigate A2074C and A2075G mutations of macrolide resistance, it was determined as 7 (16%) and 21 (48%) of the isolates. To detect quinolone resistance, the rates of quinolone resistance-determining regions (QRDR) were 20 (45.4%) and the gyrA gene mutations in the mismatch amplification mutation assay PCR (MAMA-PCR), were 19 (43.1%) of isolates. In addition, the quinolone resistance gene (qnr) carried by plasmid in Campylobacter isolates was not found in the study. BlaOXA-61 and CmeB (multi-drug efflux pump) genes were detected as 28 (63.6%) and 30 (68.1), respectively. The Enterobacterial Repetitive Intergenic Consensus PCR (ERIC-PCR) used for typing the isolates revealed that the band profiles obtained from the isolates were different. In conclusion, this was a very comprehensive study revealing the presence of antibiotic-resistant C. jejuni and C. coli with various virulence genes in patients admitted to a university hospital with acute gastroenteritis. This is of utmost significance for public health. Since campylobacteria are foodborne, zoonotic pathogens and transmission occurs mostly through food. People should have detailed information about the transmission routes of campylobacteria and risky foods. In addition, staff, food processors and caterers, should be trained in hygiene.

Porcine carcasses as an underestimated source of antimicrobial resistant Campylobacter coli

Introduction

Campylobacteriosis is the most common human foodborne bacterial infection worldwide and is caused by bacteria of the Camplylobacter genus. The main source of these bacteria is poultry, but other food-producing animals such as pigs are also responsible for human infections. An increasing number of strains with resistance to fluoroquinolones and other antimicrobials such as macrolides were recently noted. The aim of the study was to investigate Campylobacter contamination of porcine carcasses and determine the antimicrobial resistance of the obtained isolates.

Material and Methods

A total of 534 swabs from carcasses of pigs slaughtered in Poland during 2019-2022 were tested for Campylobacter spp.

Results

Campylobacter was detected in 164 (30.7%) carcasses; among them 149 (90.8%) were classified as C. coli and the remaining 15 (9.2%) samples were C. jejuni-positive. Because a low number of C. jejuni isolates were identified, only the C. coli isolates were subjected to antimicrobial resistance analysis. The majority of these isolates were resistant to streptomycin (94.0%), ciprofloxacin (65.8%) and tetracycline (65.1%). A total of 94 (63.1%) strains displayed antimicrobial multiresistance patterns and were mainly resistant to fluoroquinolones, aminoglycosides and tetracyclines (74; 49.7% of the isolates tested).

Conclusion

The obtained results showed that pig carcasses may be contaminated with antimicrobial-resistant C. coli.

Genetic Diversity and Resistome Analysis of Campylobacter lari Isolated from Gulls in Croatia

Campylobacter lari is a thermotolerant bacterium that sporadically causes gastrointestinal diseases in humans and can be found in wildlife and the environment. C. lari is an understudied species, especially in wild birds such as gulls. Gulls are potentially good carriers of pathogens due to their opportunistic behavior and tendency to gather in large flocks. During winter and their breeding period, 1753 gulls were captured, and cloacal swabs were taken to be tested for the presence of C. lari. From isolated bacteria, the DNA was sequenced, and sequence types (ST) were determined. Sixty-four swabs were positive for C. lari, and from those, forty-three different STs were determined, of which thirty-one were newly described. The whole genome was sequenced for 43 random isolates, and the same isolates were tested for antimicrobial susceptibility using the broth microdilution method to compare them to WGS-derived antimicrobial-resistant isolates. All the tested strains were susceptible to erythromycin, gentamicin, and chloramphenicol, and all were resistant to ciprofloxacin. Resistance to ciprofloxacin was attributed to a gyrA_2 T86V mutation. Genes connected to possible beta-lactam resistance (blaOXA genes) were also detected.

Genomic Characterization of Campylobacter jejuni Associated with Perimyocarditis: A Family Case Report

Campylobacter spp. is the leading cause of foodborne gastrointestinal infections in humans worldwide. This study reports the first case of four family members who had contact with the same source of Campylobacter jejuni contamination with different results. Only the little siblings were infected by the same C. jejuni strain, but with different symptoms. Whereas the daughter was slightly affected with mild enteritis, the son suffered a longer campylobacteriosis followed with a perimyocarditis. This is the first case of the youngest patient affected by C. jejuni-related perimyocarditis published to date. The genomes of both strains were characterized by whole-genome sequencing and compared with the C. jejuni NCTC 11168 genome to gain insights into the molecular features that may be associated with perimyocarditis. Various comparison tools were used for the comparative genomics analysis, including the identification of virulence and antimicrobial resistance genes, phase variable (PV) genes, and single nucleotide polymorphisms (SNPs) identification. Comparisons of the strains identified 16 SNPs between them, which constituted small but significant changes mainly affecting the ON/OFF state of PV genes after passing through both hosts. These results suggest that PV occurs during human colonization, which modulates bacteria virulence through human host adaptation, which ultimately is related to complications after a campylobacteriosis episode depending on the host status. The findings highlight the importance of the relation between host and pathogen in severe complications of Campylobacter infections.

Genomic and Antimicrobial Surveillance of Campylobacter Population in Italian Poultry

Campylobacter is one of the most common foodborne diseases worldwide with increasing rates of antibiotic resistance. Most cases of campylobacteriosis can be traced back to the consumption of poultry meat. Despite many efforts to reduce contamination in farms and in slaughterhouses, the persistence of this pathogen in poultry products remains a problem. This study aimed to evaluate the genetic diversity and antibiotic resistance of 542 C. jejuni and C. coli in Italian poultry, in the framework of two National Monitoring Programs. Genomes were screened for antibiotic resistance, virulence determinants and contextualized within a global collection of C. jejuni. ST2116, ST2863 and ST 832 were the most prevalent and significantly associated with Italian poultry. A worrying increase in resistance to quinolones, fluoroquinolones and tetracycline was observed in C. jejuni, while an increased occurrence of multidrug resistant (MDR) strains and strains resistant to macrolides was detected in C. coli. Low resistance rates were found for aminoglycosides. Molecular resistance determinants were consistent with the phenotypic resistance for tetracycline and quinolones. In silico analysis revealed 119 genes associated with virulence factors, with a notably higher prevalence of some genes in ST2863 genomes. This study highlights the increased resistance to macrolides and the emergence of MDR strains for C. coli, the genetic basis of AMR and the predominance of two genotypes among Campylobacter strains isolated from the Italian poultry farms.

First Report of Campylobacter jejuni Strains Belonging to ST-21 Clonal Complex Isolated from Human, Poultry and Wild Birds in Croatia: Antimicrobial Resistance and Genetic Distance

In the era of growing antimicrobial resistance, a threat affecting humans, endangering animals, as well as livelihoods and food security worldwide, we wanted to find possible explanations for its continuous spread from a new perspective. The ubiquity of resistance genes requires a One Health approach to finding the explanations for continuous AMR spread. The natural transformability of Campylobacter jejuni, its high incidence of infections, and emerging resistance worldwide inspired us to choose C. jejuni ST-21CC to be our pathogen for analyzing its contribution and connection to the cycle of AMR dissemination. ST-21CC is known as a generalist among humans and broilers, the most prevalent lineage worldwide, but it is rarely found in wild birds. Emerging in wild birds, genetic relatedness and similar resistance profiles were expected. We analyzed 23 Croatian C. jejuni strains belonging specifically to ST-21CC from humans, broilers, and wild birds. The genomic data obtained through whole genome sequencing and phenotypic susceptibility data of strains were compared. Our findings suggest high fluoroquinolone resistance in ST-21CC strains, with more diverse genetic backgrounds in wild birds. Intriguing were three isolates of ST-822 (from human and storks), sharing a similar genetic fingerprint.

Study of Zoonotic Pathogens in Alien Population of Veiled Chameleons (Chamaeleo calyptratus) in the Canary Islands (Spain)

Veiled chameleons (Chamaeleo calyptratus) are native to the Arabian Peninsula that have been introduced as pets in many regions around the world, such as the Canary Islands (Spain). In this work, the gastrointestinal content from veiled chameleons of Gran Canaria island (Canary Islands) has been analyzed to determine the presence of zoonotic bacteria. Forty animals were analyzed using different selective culture media and PCR. The most isolated bacteria were Yersinia enterocolitica (52.4%), followed by Salmonella spp. (40.0%), with positive isolates for Salmonella Tyhpi and Salmonella Typhimurium. Pseudomonas spp. was found in 32.5% of the chameleons. More than half were positive for Pseudomonas aeruginosa. Antibiotic-resistant Staphylococcus spp. was detected in six animals plus one isolate of non-resistant Staphylococcus hominis. Multiple mycobacteria species belonging to both tuberculous and non-tuberculous complexes were identified as well as Escherichia coli carrying the stx₁ and eae virulence genes with 12.5% and 7.5% prevalence, respectively. Listeria monocytogenes, Campylobacter spp., and Vibrio spp. were found in lower proportion (<5%). The results obtained indicate that veiled chameleons in Gran Canaria could be playing a role in the maintenance and dissemination of the pathogens detected, harming public health and biodiversity.

Investigation of the Effect of Three Commercial Water Acidifiers on the Performance, Gut Health, and Campylobacter jejuni Colonization in Experimentally Challenged Broiler Chicks

This study investigated the effect of three commercial water acidifiers on the performance, gut health, and C. jejuni colonization in experimentally challenged broiler chicks. A total of 192 one-day-old broiler chicks (Ross 308^®) were randomly allocated into 6 treatment groups with 4 replicates according to the following experimental design: group A, birds were not challenged and received tap water; group B, birds were challenged and received tap water; groups C, D, E, and F, birds were challenged and received tap water treated with 0.1% v/v SPECTRON^®, with 0.1-0.2% v/v ProPhorce™ SA Exclusive, with 0.1-0.2% v/v Premium acid, and with 0.1-0.2% v/v Salgard^® Liquid, respectively. The continuous water acidification evoked undesirable effects on broilers' performance and to an increased number of birds with ulcers and erosions in the oral cavity and the upper esophageal area. ProPhorce™ SA Exclusive and Premium acid significantly reduced the C. jejuni counts in the crop, whereas Salgard^® Liquid significantly reduced the C. jejuni counts in the ceca of birds. At slaughter age, only Premium acid significantly reduced C. jejuni counts in the ceca of birds. All the tested products ameliorated the changes induced by C. jejuni infection in the pH in the ceca of birds. It can be concluded that besides the effectiveness of the tested products in controlling C. jejuni in broilers, their continuous application evoked undesirable effects on broilers' performance, leading to the need to modify the dosage scheme in future investigations.

Circulation of thermophilic Campylobacter in pigeons, turkeys, and humans at live bird markets in Egypt

Live bird markets increase the risk of transmission of zoonotic diseases. Few studies have investigated the potential zoonotic transmission of Campylobacter in Egypt. Therefore, our study was carried out to investigate the presence of Campylobacter species, mainly Campylobacter jejuni (C. jejuni) and Campylobacter coli (C. coli), in pigeons and turkeys sold at poultry shops. Furthermore, the study aimed to explore the potential occupational risk of Campylobacter infection, mainly among workers at poultry shops. Six hundred (n = 600) samples from various organs were obtained from pigeons and turkeys from live bird shops in the Giza and Asyut provinces in Egypt. Additionally, 100 stool samples were collected from persons working at poultry shops. Circulation of thermophilic Campylobacter in pigeons, turkeys, and humans was investigated based on culture and molecular methods. The rate of detection of Campylobacter species from the samples was significant when the culture method was used alone in comparison to when it was used in combination with mPCR. The prevalence rates of Campylobacter species detected by mPCR were 36% (C. jejuni 20%; C. coli 16%), 28% (C. jejuni 12%; C. coli16%), and 29% (C. jejuni 15%; C. coli 14%) in pigeons, turkeys, and workers, respectively. In pigeons, significant variations in the C. jejuni and C. coli occurrence rates were reported in terms of the intestinal content (15, 4%), liver (4, 13%), and skin (9, 7%), respectively. In turkeys, Campylobacter species were mostly detected in liver samples with a percentage of 19%, followed by the skin (12%), and the intestinal content (8%). In conclusion, Campylobacter species are circulating in poultry farms in Egypt and could represent a hazard for humans. It is recommended that biosecurity measures should be applied to mitigate the occurrence of Campylobacter in poultry farms. Moreover, there is an urgent need to transform live bird markets into chilled poultry markets.

Detection of Potential Zoonotic Agents Isolated in Italian Shelters and the Assessment of Animal Welfare Correlation with Antimicrobial Resistance in Escherichia coli Strains

Welfare conditions in shelters, where dogs might be housed for a long period of time, may have a possible correlation with the occurrence of bacterial pathogens and their antimicrobial resistance (AMR). In this study, we assessed the occurrence of AMR in 54 strains of Escherichia coli isolated from dogs housed in 15 Italian shelters and we correlated the resistance patterns to animal welfare. We also aimed to evaluate the presence of specific pathogens with zoonotic potential in sheltered dogs. Thus, nasopharyngeal, rectal, and oral swabs were collected from a group of 20 dogs in each shelter and totaled 758 swabs. We identified 9 Staphylococcus pseudointermedius, 1 Pasteurella multocida, 9 Staphylococcus aureus, 12 Campylobacter spp., 54 Escherichia coli, 2 Salmonella enterica, and 246 Capnocytophaga spp. The antimicrobial susceptibility was assessed for the E. coli isolates using a panel of 14 antibiotics. The highest level of relative AMR was recorded for ampicillin and sulfamethoxazole. The association found between AMR and the levels of animal welfare scores in shelters was evident although not statistically significant. These results support the hypothesis that the good management of shelters can increase the level of animal welfare, thus reducing the use of antibiotics and, as a consequence, the AMR occurrence found in dogs that share their domestic environment with humans.

Validation of PCR methods for confirmation and species identification of thermotolerant Campylobacter as part of EN ISO 10272 - Microbiology of the food chain - Horizontal method for detection and enumeration of Campylobacter spp

This article describes the outline and organisation of the validation of three multiplex PCR methods for species identification and/or confirmation of thermotolerant Campylobacter spp. The three PCR methods were validated against the reference method described in the EN ISO standard 10272:2017. The results of the PCR methods were compared against the reference method in a method comparison study and an interlaboratory study based on EN ISO 16140-6:2019. The performance, in terms of inclusivity and exclusivity, of each of the eight PCR targets were comparable to the performance of the reference method: close, equal, or better depending on the target. In total, all three PCR methods were concluded to be equally qualified as the reference method for molecular identification and/or confirmation of thermotolerant Campylobacter spp., C. jejuni, C. coli and C. lari isolated from the food chain and have been included in Amendment 1 of ISO 10272:2017.

Occurrence of Campylobacter in Faeces, Livers and Carcasses of Wild Boars Hunted in Tuscany (Italy) and Evaluation of MALDI-TOF MS for the Identification of Campylobacter Species

A total of 193 wild boars hunted in Tuscany, an Italian region with a high presence of wild ungulates, were examined to assess the occurrence of Campylobacter species in faeces, bile, liver and carcasses, with the aim of clarifying their contribution to human infection through the food chain. Campylobacter spp. were found in 44.56% of the animals, 42.62% of the faecal samples, 18.18% of the carcass samples, 4.81% of the liver tissues and 1.97% of the bile samples. The Campylobacter species genotypically identified were C. coli, C. lanienae, C. jejuni and C. hyointestinalis. The prevalent species transpired to be C. coli and C. lanienae, which were isolated from all the matrices; C. jejuni was present in faeces and liver, while C. hyointestinalis only in faeces. Identification was carried out by matrix-assisted laser desorption/ionisation-time-of-flight mass spectrometry (MALDI-TOF MS) on 66 out of 100 isolates identified genotypically, and the technique yielded unsatisfactory results in the case of C. lanienae, which is responsible for sporadic human disease cases. The level of Campylobacter spp. contamination of meat and liver underlines the need to provide appropriate food safety information to hunters and consumers.

Zoonotic Bacteria in Anolis sp., an Invasive Species Introduced to the Canary Islands (Spain)

Lizards belonging to the genus Anolis are native to America and have been introduced in many parts of the world. In this work, a gastrointestinal microbiological analysis from Anolis sp. introduced to Tenerife, Canary Island, was carried out. A total of 74 individuals were analyzed by culture and molecular tools. Pseudomonas spp. was the most prevalent bacteria isolated (64.3%), followed by enteropathogenic Escherichia coli with at least one of the investigated virulent genes (stx₁, stx₂, and eae) (44.6%). The stx₂ gene was more prevalent which differs to that reported in other reptiles, probably due to wastewater transmission. Campylobacter spp. was detected in 32.4% of the animals, highlighting the detection of C. jejuni and C. fetus by their relevance to public health. The zoonotic Staphylococcus lugdunensis, found in 14.9% of the animals, was firstly detected in reptiles. Vibrio sp. which is more associated with aquatic environments was found in 10.8% of the lizards in this study, with Vibrio cholerae being found in two of the animals. The prevalence of Salmonella sp. (5.4%) was low, compared with other studies carried out in reptiles. These results indicate that Anolis sp. in Tenerife could be playing a role in the maintenance and spread of the pathogens detected, being a possible risk factor for public health and biodiversity conservation.

Molecular Prevalence and Risk Factors of Campylobacter Infection in Puppies in the Nairobi Metropolitan Region, Kenya

Campylobacter species are widely distributed pathogens; however, data on its epidemiology in puppies remain scanty, especially in Kenya. A cross-sectional study was conducted in the Nairobi Metropolitan Region to determine molecular prevalence and associated risk factors of Campylobacter species infection in puppies. A total of 260 rectal swabs were collected from puppies from breeding kennels, shelters, and the University of Nairobi Veterinary Teaching and Referral Hospital. The samples were subjected to polymerase chain reaction (PCR) assays for identification of Campylobacter species. Data on potential risk factors associated with puppy exposure were collected using a semistructured questionnaire. Multivariable mixed effects logistic regression analyses were performed with kennels as random effects. Campylobacter species were detected in 64 of the 260 sampled puppies yielding an overall prevalence of 24.6%. Multivariable results showed that puppies from shelters, puppies from kennels that are washed daily, puppies with a recent history of vomiting, and those treated with antibiotics in the past month were significantly associated with the presence of Campylobacter species. Being a kenneled puppy and having had concurrent bacterial infections were identified as protective factors. This study provides molecular evidence of puppy exposure to Campylobacter species which could have impact on puppy health and highlights the need to develop awareness and management strategies to potentially reduce the risk of transmitting this pathogen among puppies, to humans, and other animals.

Genomic Insights into the Increased Occurrence of Campylobacteriosis Caused by Antimicrobial-Resistant Campylobacter coli

Campylobacter is the leading bacterial cause of diarrheal illnesses worldwide. Campylobacter jejuni and C. coli are the most common species accounting for campylobacteriosis. Although the proportion of campylobacteriosis caused by C. coli is increasing rapidly in China, the underlying mechanisms of this emergence remain unclear. In this study, we analyzed the whole-genome sequences and associated environments of 1,195 C. coli isolates with human, poultry, or porcine origins from 1980 to 2021. C. coli isolates of human origin were closely related to those from poultry, suggesting that poultry was the main source of C. coli infection in humans. Analysis of antimicrobial resistance determinants indicated that the prevalence of multidrug-resistant C. coli has increased dramatically since the 2010s, coinciding with the shift in abundance from C. jejuni to C. coli in Chinese poultry. Compared with C. jejuni, drug-resistant C. coli strains were better adapted and showed increased proliferation in the poultry production environment, where multiple antimicrobial agents were frequently used. This study provides an empirical basis for the molecular mechanisms that have enabled C. coli to become the dominant Campylobacter species in poultry; we also emphasize the importance of poultry products as sources of campylobacteriosis caused by C. coli in human patients. IMPORTANCE The proportion of campylobacteriosis caused by C. coli is increasing rapidly in China. Coincidentally, the dominant species of Campylobacter occurring in poultry products has shifted from C. jejuni to C. coli. Here, we analyzed the whole-genome sequences of 1,195 C. coli isolates from different origins. The phylogenetic relationship among C. coli isolates suggests that poultry was the main source of C. coli infection in humans. Further analysis indicated that antimicrobial resistance in C. coli strains has increased dramatically since the 2010s, which could facilitate their adaptation in the poultry production environment, where multiple antimicrobial agents are frequently used. Thus, our findings suggest that the judicious use of antimicrobial agents could mitigate the emergence of multidrug-resistant C. coli strains and enhance clinical outcomes by restoring drug sensitivity in Campylobacter.

Genomic Diversity of Campylobacter lari Group Isolates from Europe and Australia in a One Health Context

Members of the Campylobacter lari group are causative agents of human gastroenteritis and are frequently found in shellfish, marine waters, shorebirds, and marine mammals. Within a One Health context, we used comparative genomics to characterize isolates from a diverse range of sources and geographical locations within Europe and Australia and assess possible transmission of food, animal, and environmental isolates to the human host. A total of 158 C. lari isolates from Australia, Denmark, France, and Germany, which included 82 isolates from human stool and blood, 12 from food, 14 from domestic animal, 19 from waterbirds, and 31 from the environment were analyzed. Genome-wide analysis of the genetic diversity, virulence, and antimicrobial resistance (AMR) traits was carried-out. Most of the isolates belonged to C. lari subsp. lari (Cll; 98, 62.0%), while C. lari subsp. concheus and C. lari urease-positive thermotolerant Campylobacter (UPTC) were represented by 12 (7.6%) and 15 (9.5%) isolates, respectively. Furthermore, 33 (20.9%) isolates were not assigned a subspecies and were thus attributed to distant Campylobacter spp. clades. Whole-genome sequence-derived multilocus sequence typing (MLST) and core-genome MLST (cgMLST) analyses revealed a high genetic diversity with 97 sequence types (STs), including 60 novel STs and 14 cgMLST clusters (≤10 allele differences), respectively. The most prevalent STs were ST-21, ST-70, ST-24, and ST-58 (accounting for 13.3%, 4.4%, 3.8%, and 3.2% of isolates, respectively). A high prevalence of the 125 examined virulence-related loci (from 76.8 to 98.4% per isolate) was observed, especially in Cll isolates, suggesting a probable human pathogenicity of these strains. IMPORTANCE Currently, relatedness between bacterial isolates impacting human health is easily monitored by molecular typing methods. These approaches rely on discrete loci or whole-genome sequence (WGS) analyses. Campylobacter lari is an emergent human pathogen isolated from diverse ecological niches, including fecal material from humans and animals, aquatic environments, and seafood. The presence of C. lari in such diverse sources underlines the importance of adopting an integrated One Health approach in studying C. lari population structure for conducting epidemiological risk assessment. This retrospective study presents a comparative genomics analysis of C. lari isolates retrieved from two different continents (Europe and Australia) and from different sources (human, domestic animals, waterbirds, food, and environment). It was designed to improve knowledge regarding C. lari ecology and pathogenicity, important for developing effective surveillance and disease prevention strategies.

The Prevalence of Salmonella and Campylobacter on Broiler Meat at Different Stages of Commercial Poultry Processing

In poultry processing, Salmonella and Campylobacter contaminations are major food safety concerns. Peracetic acid (PAA) is an antimicrobial commonly used in commercial poultry processing to reduce pathogen prevalence so as to meet the USDA-FSIS performance standards. The objective of this study was to determine the prevalence of Salmonella and Campylobacter on broiler meat in various steps of commercial poultry processing in plants that use PAA. Post-pick, pre-chill, post-chill, and drumstick chicken samples were collected from three processing plants and mechanically deboned meat (MDM) was collected from two of the three plants. Each plant was sampled thrice, and 10 samples were collected from each processing step during each visit. Among the 420 samples, 79 were contaminated with Salmonella and 155 were contaminated with Campylobacter. Salmonella and Campylobacter contamination on the post-pick samples averaged 32.2%. Significant reductions in Salmonella and Campylobacter were observed in pre-chill to post-chill samples, where the prevalence was reduced from 34% and 64.4% to nondetectable limits and 1.1%, respectively (p < 0.001). Salmonella and Campylobacter remained undetectable on the drumstick samples in all three processing plants. However, the prevalence of Salmonella and Campylobacter on MDM was similar to the post-pick prevalence, which suggests substantial cross-contamination from post-chill to MDM.

First Data on Campylobacter spp. Presence in Shellfish in Croatia

This study aimed to assess the presence of thermotolerant Campylobacter spp., as one of the most important foodborne zoonotic pathogens, in three shellfish species: mussels (Mytilus galloprovincialis), oysters (Ostrea edulis) and queen scallops (Aequipecten opercularis). The samples were collected from nine locations in the Istrian aquatory, Croatia. Isolation of Campylobacter was done according to standard ISO method, and species were identified using multiplex PCR. Isolates identified as C. jejuni and C. lari were genotyped using multilocus sequence typing (MLST) to determine the potential source of contamination. Among 108 examined samples of bivalve molluscs, mussels dominated and were the only ones found positive for the presence of Campylobacter (25.6%). In total, 19 C. lari and 1 C. jejuni strains were isolated. C. lari isolates found in this study belong to 13 sequence types (STs), and 9 of them are newly described in this paper. Two out of the four previously described C. lari STs that were found in this study were previously found in human stool. The only C. jejuni isolate was found to be sequence type 1268, which belongs to ST-1275 clonal complex that is almost exclusively found in seabirds and can sporadically cause infection in humans. Regarding the obtained results, introducing surveillance of thermotolerant Campylobacter in shellfish in the Republic of Croatia is advised as an improvement for public health safety.

Resistome Analysis of Campylobacter jejuni Strains Isolated from Human Stool and Primary Sterile Samples in Croatia

Campylobacteriosis represents a global health challenge due to continuously increasing trends of antimicrobial resistance in Campylobacter jejuni. C. jejuni can sometimes cause life-threatening and severe systematic infections (bacteremia, meningitis, and other extraintestinal infections) with very few antibiotics left as treatment options. Bearing in mind that C. jejuni is the predominant species in humans, in this paper, we present a study of the C. jejuni differences in antimicrobial resistance and genotype distribution between strains isolated from stool and primary sterile sites. We compared the genomic data obtained through whole genome sequencing (WGS) and phenotypic susceptibility data of C. jejuni strains. Once antimicrobial susceptibility testing of C. jejuni strains was carried out by the broth microdilution method for six of interest, results were compared to the identified genotypic determinants derived from WGS. The high rate of resistance to fluoroquinolones presented in this study is in accordance with national surveillance data. The proportion of strains with acquired resistance was 71% for ciprofloxacin and 20% for tetracycline. When invasive isolates were analysed separately, 40% exhibited MIC values of ciprofloxacin higher than the ECOFFs, suggesting a lower flouroquinolone resistance rate in invasive isolates. All isolates demonstrated wilde-type phenotype for chloramphenicol, erythromycin, gentamicin, and ertapenem. A special focus and review in this study was performed on a group of C.jejuni strains found in primary sterile samples. Apart from demonstrating a lower resistance rate, these isolates seem genetically more uniform, showing epidemiologically more homogenous patterns, which cluster to several clonal complexes, with CC49 being the most represented clonal complex.

Occurrence and Multidrug Resistance of Campylobacter in Chicken Meat from Different Production Systems

Campylobacter is the leading bacterial cause of diarrheal disease worldwide and poultry remains the primary vehicle of its transmission to humans. Due to the rapid increase in antibiotic resistance among Campylobacter strains, the World Health Organization (WHO) added Campylobacter fluoroquinolone resistance to the WHO list of antibiotic-resistant “priority pathogens”. This study aimed to investigate the occurrence and antibiotic resistance of Campylobacter spp. in meat samples from chickens reared in different production systems: (a) conventional, (b) free-range and (c) backyard farming. Campylobacter spp. was detected in all samples from conventionally reared and free-range broilers and in 72.7% of backyard chicken samples. Levels of contamination were on average 2.7 × 10³ colony forming units (CFU)/g, 4.4 × 10² CFU/g and 4.2 × 10⁴ CFU/g in conventionally reared, free-range and backyard chickens, respectively. Campylobacter jejuni and Campylobacter coli were the only species isolated. Distribution of these species does not seem to be affected by the production system. The overall prevalence of Campylobacter isolates exhibiting resistance to at least one antimicrobial was 98.4%. All the C. coli isolates showed resistance to ciprofloxacin and to nalidixic acid, and 79.5 and 97.4% to ampicillin and tetracycline, respectively. In total, 96.2% of C. jejuni isolates displayed a resistant phenotype to ciprofloxacin and to nalidixic acid, and 92.3% to ampicillin and tetracycline. Of the 130 Campylobacter isolates tested, 97.7% were classified as multidrug resistant (MDR).

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.

Prevalence and Antimicrobial Susceptibility of Campylobacter Species with Particular Focus on the Growth Promoting, Immunostimulant and Anti-Campylobacter jejuni Activities of Eugenol and Trans-Cinnamaldehyde Mixture in Broiler Chickens

Simple Summary

Campylobacter species are the leading cause of foodborne bacterial enteritis worldwide. Recently, extensively drug-resistant (XDR) and multi-drug-resistant (MDR) Campylobacter spp. have caused several global crises. Therefore, the present work aims to detect the prevalence and antimicrobial resistance patterns of Campylobacter spp. from various chicken sources in Egypt, and to investigate the efficacy of a mixture of eugenol and trans-cinnamaldehyde on the performance and immunity of challenged broilers and also to assess their effects on C. jejuni load and virulence gene expression in an in vivo model. Our results showed a high prevalence of campylobacter isolates (67.3%). Of note, 25.7 and 74.3% of campylobacter isolates were XDR and MDR, respectively. Interestingly, a mixture of eugenol and trans-cinnamaldehyde had significant enhancing and antimicrobial effects through improving the growth-performance variables, minimizing the C. jejuni fecal loads, and decreasing the C. jejuni virulence genes (flaA, virB11, and wlaN) expressions in broilers challenged with C. jejuni. Moreover, the mixture of eugenol and the trans-cinnamaldehyde had immunostimulant and anti-inflammatory activities. In conclusion, our findings suggest that the utilization of the mixture of eugenol and trans-cinnamaldehyde has a growth-promoting role and can be considered as a better replacement of the antimicrobial agents for the control and treatment of campylobacter infection in broiler chickens.

Abstract

Campylobacter species (spp.) are one of the most important causes of human bacterial gastroenteritis in foods of animal origin. Recently, with the spread of multi-drug-resistant (MDR) and extensively drug-resistant (XDR) Campylobacter spp., natural alternative therapeutic methods are urgently required. Phytogenic active principles have gained considerable attention due to their proficiency to enhance gut health and, thereby, performance of broiler chickens. Thus, the current study aims to determine the prevalence and antimicrobial resistance of Campylobacter spp. of different chicken sources in Sharkia Governorate, Egypt, and to assess the growth-promoting, immunostimulant and antimicrobial effects of a mixture of eugenol and trans-cinnamaldehyde in an in vivo approach. A total of 101 (67.3%) campylobacter isolates was identified, according to both phenotypic and genotypic techniques. Moreover, all of the campylobacter isolates were resistant to erythromycin, trimethoprim/sulfamethoxazole, and ampicillin (100% each). Of note, a dietary supplementation of the mixture of eugenol and trans-cinnamaldehyde led to a significant improvement of the feed conversion ratio and body weight gain and a decrease in the cecal C. jejuni loads in the broilers challenged with XDR C. jejuni. Additionally, eugenol and the trans-cinnamaldehyde mixture had protective activities via the down-regulation of XDR C. jejuni (flaA, virB11 and wlaN) virulence genes and proinflammatory cytokines (TNF-α, IL-2, IL-6, and IL-8), and the up-regulation of anti-inflammatory cytokine IL-10. Thus, we recommend the usage of a mixture of eugenol and trans-cinnamaldehyde as an alternative to antimicrobials for the control and treatment of campylobacter infections.

In Vitro assessment of anti-Campylobacter activity of lactobacillus strains isolated from canine rectal swabs

Background

Campylobacteriosis is currently the most frequently reported zoonosis. Dogs, especially puppies or those with diarrhea, are considered a possible source of human infection. Probiotic bacteria, such as Lactobacillus species, seem to be a valuable tool in controlling of intestinal pathogenic microorganisms in dogs. The main purpose of this study was to assess the anti-Campylobacter activity and some probiotic properties, like ability to produce H₂O_2, bile salt and low pH tolerance of Lactobacillus strains isolated from gastrointestinal tract of healthy dogs.

Results

A total of 39 rectal swabs derived from healthy dogs and 19 from dogs with diarrhea were examined to detect Lactobacillus and Campylobacter bacteria respectively. In total, 30 strains of Lactobacillus genus and four strains of Campylobacter genus were isolated and identified. Of the 30 strains of Lactobacillus, 22 showed an inhibitory effect towards Campylobacter. Four strains with the strongest antagonism towards Campylobacter bacteria (L. salivarius 25 K/L/1, L. rhamnosus 42 K/L/2, L. sakei 50 K/L/1 and L. agilis 55 K/L/1) were selected to assess their potential probiotic traits. Three out of four analyzed strains produced extracellular H₂O_2. All displayed very good or moderate survival at pH 3.0 and 2.0 and showed high tolerance to 0.5% and 1% bile salts.

Conclusions

Among selected Lactobacillus strains, all may have a potential probiotic application in reducing Campylobacter spp. in dogs and thus prevent transmission of infection to humans, although the best candidate for probiotic seems to be L. sakei 50 K/L/1. Further in vitro and in vivo studies are needed.

A Cutoff Determination of Real-Time Loop-Mediated Isothermal Amplification (LAMP) for End-Point Detection of Campylobacter jejuni in Chicken Meat

Campylobacter jejuni is one of the leading causes of foodborne illness worldwide. C. jejuni is commonly found in poultry. It is the most frequent cause of contamination and thus resulting in not only public health concerns but also economic impacts. To test for this bacterial contamination in food processing plants, this study attempted to employ a simple and rapid detection assay called loop-mediated isothermal amplification (LAMP). The best cutoff value for the positive determination of C. jejuni calculated using real-time LAMP quantification cycle (Cq) was derived from the receiver operating characteristic (ROC) curve modeling. The model showed an area under curve (AUC) of 0.936 (95% Wald CI: 0.903–0.970). Based on Youden’s J statistic, the optimal cutoff value which had the highest sensitivity and specificity from the model was calculated as 18.07. The LAMP assay had 96.9% sensitivity, 95.8% specificity, and 93.9 and 97.9% positive and negative predictive values, respectively, compared to a standard culture approach for C. jejuni identification. Among all non-C. jejuni strains, the LAMP assay gave each of 12.5% false-positive results to C. coli and E. coli (1 out of 8 samples). The assay can detect C. jejuni at the lowest concentration of 103 CFU/mL. Our results suggest a preliminary indicator for the application of end-point LAMP assays, such as turbidity and UV fluorescence tests, to detect C. jejuni in field operations. The LAMP assay is an alternative screening test for C. jejuni contamination in food samples. The method provides a rapid detection, which requires only 9 min with a cutoff value of Cq. We performed the extraction of DNA from pure cultures and the detection of C. jejuni using the LAMP assay within 3 h. However, we were not able to reduce the time for the process of enrichment involved in our study. Therefore, we suggest that alternative enrichment media and rapid DNA extraction methods should be considered for further study. Compared to other traditional methods, our proposed assay requires less equipment and time, which is applicable at any processing steps in the food production chain.

Prevalence and Characterization of Quinolone Resistance in Campylobacter spp. Isolates in Chicken Livers from Retail Stores in Georgia, USA

ABSTRACT

Campylobacter is a bacterial pathogen that causes human foodborne illnesses worldwide, and outbreaks have been associated with consumption of undercooked chicken livers. The objectives of this study were to compare two PCR assays of 250 Campylobacter isolates for identification to species, to assess antibiotic resistance of the isolates, and to analyze genetic diversity of the quinolone resistance determining regions (QRDRs) of the isolates. A double-blind design was used to identify the species of Campylobacter; 181 (72%) of the isolates were identified as Campylobacter jejuni, and 69 (28%) isolates were identified as Campylobacter coli by both PCR assays. A total of 93 (37.2%) isolates were resistant to at least one antibiotic. Among 88 C. jejuni isolates, 33 (18%) were resistant to nalidixic acid (NAL) and ciprofloxacin (CIP), 25 (14%) were resistant to tetracycline (TET), and 18 (10%) were resistant to NAL and TET. Two C. jejuni isolates were resistant to four of the tested antibiotics, and one isolate was resistant to five antibiotics. Two C. coli isolates were resistant to TET, and two were resistant to NAL, CIP, and TET. The amino acid sequences of the QRDRs for the isolates had eight point mutations and could be classified into 12 groups. Thirty-eight C. jejuni isolates resistant to NAL and CIP had a point mutation at residue 86 (substitution from threonine to isoleucine). However, six isolates without this substitution were resistant to NAL and/or CIP. Ten isolates with a point mutation at residue 86 were susceptible to NAL and CIP. This observation suggests that in addition to the substitution at residue 86 other mechanisms may confer resistance to quinolones. Further studies are needed to elucidate mechanisms for quinolone resistance in Campylobacter. The Campylobacter spp. isolated from chicken livers in this study were resistant to quinolones and other classes of antibiotics.

HIGHLIGHTS

Investigation of Antimicrobial Susceptibilities and Resistance Genes of Campylobacter Isolates from Patients in Edirne, Turkey

Background

We aimed to determine the susceptibility of Campylobacter isolates obtained from patients to various antimicrobial agents and to investigate some related antimicrobial resistance genes.

Methods

Fifty-six Campylobacter isolates obtained from fecal specimens by conventional methods at the Trakya University Health Center for Medical Research and Practice, Department of Medical Microbiology in Edirne, Turkey, from 2017-2017 were included. Antimicrobial susceptibilities were investigated by the gradient strip test method, and species determination was made by multiplex polymerase chain reaction (mPCR). The presence of the erm(B) gene and tet(O) gene was investigated in all isolates by PCR. DNA sequence analysis was performed to detect the presence of mutations in the 23S rRNA positions 2074 and 2075 in five isolates, including two erythromycin resistant isolates. The gyrA gene mutation was investigated by the mismatch amplification mutation assay (MAMA)-PCR.

Results

In 54 C. jejuni isolates, resistance to erythromycin was 3.7%; to tetracycline, 59.3%; and to ciprofloxacin, 74.1%. Phenotypically, the tet(O) gene was detected in 33 tetracycline-resistant isolates, but no erm(B) gene was found in any of the Campylobacter isolates. As a result of the DNA sequencing, it was found no mutations in the 23S rRNA gene at the 2074 and 2075 positions. The gyrA mutation was observed in all 41 ciprofloxacin resistant Campylobacter isolates.

Conclusion

Among the antimicrobial agents tested, ciprofloxacin had the highest resistance rate, and erythromycin had the lowest. Antimicrobial resistance in Campylobacter increased significantly compared with previously studies in our region as well as in the entire world. Monitoring the resistance to antimicrobial agents used to treat Campylobacter infections is important in determining empiric antimicrobial treatment.

Prevalence and whole-genome sequence analysis of Campylobacter spp. strains isolated from wild deer and boar in Japan

As a part of risk analysis for consumption of meat from wild animals, the prevalence of Campylobacter spp. in wild deer and boar in Japan was investigated. C. hyointestinalis subsp. hyointestinalis (C. hyointestinalis) was isolated from 2.8% (7/253) of the wild deer and 22.1% (71/321) of the wild boar examined. All 23 wild deer isolates and 141 (72.7%) wild boar isolates carried both chcdt-I and chcdt-II genes. The remaining 53 (27.3%) wild boar isolates had only the chcdt-II gene. By whole-genome sequence analysis, we detected 38-40 virulence- and survival-associated genes (motility, chemotactic, adhesion, invasion, toxin, glycosylation, iron uptake, drug resistance, and stress response), which had been identified in C. jejuni and C. coli. In conclusion, our study highlights C. hyointestinalis as a possible cause of food-borne disease in humans and emphasizes the importance of food hygiene in the processing of wild meats for human consumption.

Isolation and characterization of thermophilic Campylobacter species from geese raised in Kars region (Turkey) using cultural, molecular and mass spectrometry methods

BACKGROUND

Thermophilic Campylobacters are found in the digestive tract of wild and domestic poultry and can be transmitted to humans following their fecal discharges.

AIMS

This study aimed to isolate thermophilic Campylobacter by culture from cloacal swabs of geese, commonly breeding in Kars region, and to identify the isolates by PCR and mass spectrometry. Antibiotics susceptibility and resistance genes of the isolates were also analysed.

METHODS

The study included 400 cloacal swab samples of clinically healthy geese. The samples were cultured on mCCDA medium following the pre-enrichment in Preston broth. Identification of the isolates was performed by phenotypic methods, PCR, and MALDI-TOF MS. Antibiotic susceptibility and resistance genes of the isolates were analysed with the disc diffusion method and PCR, respectively.

RESULTS

Thermophilic Campylobacter spp. were isolated from 157 (39.3%) samples. 151 (96.2%) isolates were identified Campylobacter jejuni and 6 (3.8%) Campylobacter coli by the phenotypic tests and PCR. Among 125 isolates analysed by MALDI-TOF MS, 119 (95.2%) were identified C. jejuni and 6 (4.8%) C. coli. The isolates' resistance to ampicillin, tetracycline, ciprofloxacin, gentamicin, and azithromycin were found 33.8%, 41.4%, 75.2%, 12.1%, and 7.6%, respectively. The distributions of bla _OXA61, tetO, gyrA, and aphA-3 genes were 3.2%, 90.8%, 50.8%, and 52.7%, respectively.

CONCLUSION

Since geese are raised in pastures in the Kars region, protecting and not polluting the existing natural environment and preventing their contact with wild birds will prevent the spread of these microorganisms.

Performance of bovine genital campylobacteriosis diagnostic tests in bulls from Uruguay: a Bayesian latent class model approach

The sensitivity (Se) and specificity (Sp) of three diagnostic tests for the detection of Campylobacter fetus venerealis (Cfv) using field samples were estimated using a Bayesian latent class model (BLCM), accounting for the absence of a gold standard. The tests included in this study were direct immunofluorescence antibody test (IFAT), polymerase chain reaction (PCR), and real-time PCR (RT-PCR). Twelve farms from two different populations were selected and bull prepuce samples were collected. The IFAT was performed according to the OIE Manual. The conventional PCR was performed as multiplex, targeting the gene nahE for C. fetus species identification and insertion element ISCfe1 for Cfv identification. The RT-PCR was performed as uniplex: one targeting the gene nahE for C. fetus and the other targeting the insertion ISCfe1 (ISC2) for Cfv. Results from the BLCM showed a median Se of 11.7% (Bayesian credibility interval (BCI): 1.93-29.79%), 53.7% (BCI: 23.1-95.0%), and 36.1% (BCI: 14.5-71.7%) for IFAT, PCR, and RT-PCR respectively. The Sp were 94.5% (BCI: 90.1-97.9%), 97.0% (BCI: 92.9-99.3%), and 98.4% (BCI: 95.3-99.7%) for IFAT, PCR, and RT-PCR respectively. The correlation between PCR and RT-PCR was positive and low in samples from both sampled population (0.63% vs 8.47%). These results suggest that diagnostic sensitivity of the studied tests is lower using field samples than using pure Cfv strains.

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.

Genomic Characterisation of Campylobacter jejuni Isolates Recovered During Commercial Broiler Production

Background:Campylobacter is commonly transmitted to humans from chickens. Campylobacter jejuni is the species most frequently associated with human illness, and the most prevalent species recovered from poultry.

Objective: The objective of this study was to analyse a sub-population of C. jejuni from two broiler flocks on the farm and at slaughter using whole-genome sequencing to gain insights into the changes in the Campylobacter population during broiler production, including changes in virulence and antimicrobial resistance profiles.

Methods: In this study, ten composite faecal samples (n=10), obtained by pooling ten fresh faecal samples (n=10), were collected in the broiler house on two farms on days 14, 21, 28, and 34 (n=80) and ten composite (n=10) caecal samples were collected at the time of slaughter for each flock (n=20). These were tested for C. jejuni using the ISO 10272-2:2016 method. Seven isolates were randomly selected from each of the nine Campylobacter-positive sampling points (n=63) and were subjected to antimicrobial susceptibility tests. Their genomes were sequenced and the data obtained was used to characterise the population structure, virulence, antimicrobial resistance determinants and inter-strain variation.

Results: The Farm 1 isolates had three MLST types (ST257-257, ST814-661 and ST48-48) while those on Farm 2 were ST6209-464 and ST9401. Interestingly, only the MLST types positive for most of the virulence genes tested in this study persisted throughout the production cycle, and the detection of antimicrobial resistance determinants (gyrA T86I and tetO) increased after thinning and at slaughter, with the detection of new strains.

Conclusion: The persistence of the most virulent strains detected in this study throughout the production cycle has important implications for the risk to consumers and requires further investigation. The detection of new strains within the population corresponding with the time of thinning and transportation reflects previous reports and provides further evidence that these activities pose a risk of introducing new Campylobacter strains to broiler batches.

Isolation Rate of Campylobacter Spp. and Detection of Virulence Genes of Campylobacter jejuni Across the Broiler Chain

The aim of the study was to identify the isolation rate of thermotolerant campylobacters in a small-scale broiler-meat production farm over a one-year period. The second deliverable of the study was to determine the potential virulence markers. The laboratory investigation was performed on 283 samples (cloacal swabs, caeca, carcass swabs) collected on three sampling points (farm, slaughter line, and cold storage). The isolates obtained with the conventional microbiological method were confirmed with multiplex PCR for identification of campylobacters. The presence of 10 virulence genes was analyzed in the C. jejuni isolates (flaA, racR, virB11, dnaJ, wlaN, cadF, ciaB, cdtA, cdtB, cdtC). Out of 283 samples, 169 (59.7%) were confirmed as Campylobacter spp., 111 (39.2%) C. jejuni, and 43 (15.2%) C. coli. C. jejuni was the most prevalent in all sampling points. Campylobacter spp. showed a characteristically seasonal prevalence with the highest isolation rate during the warmer period of the year. We detected the cadF and ciaB genes in all C. jejuni isolates. The flaA gene was present in 50% of the examined strains. The cdt genes (cdtA, cdtB, and cdtC) were confirmed in 52.8%, 52.8%, and 47.2% of the C. jejuni strains, respectively. C. jejuni showed 15 profiles of virulence patterns with four predominant profiles.

Genome and Methylome analysis of a phylogenetic novel Campylobacter coli cluster with C. jejuni introgression

The intriguing recent discovery of Campylobacter coli strains, especially of clade 1, that (i) possess mosaic C. coli/C. jejuni alleles, (ii) demonstrate mixed multilocus sequence types (MLSTs) and (iii) have undergone genome-wide introgression has led to the speculation that these two species may be involved in an accelerated rate of horizontal gene transfer that is progressively leading to the merging of both species in a process coined ‘despeciation’. In an MLST-based neighbour-joining tree of a number of C. coli and C. jejuni isolates of different clades, three prominent Campylobacter isolates formed a seemingly separate cluster besides the previously described C. coli and C. jejuni clades. In the light of the suspected, ongoing genetic introgression between the C. coli and C. jejuni species, this cluster of Campylobacter isolates is proposed to present one of the hybrid clonal complexes in the despeciation process of the genus. Specific DNA methylation as well as restriction modification systems are known to be involved in selective uptake of external DNA and their role in such genetic introgression remains to be further investigated. In this study, the phylogeny and DNA methylation of these putative C. coli/C. jejuni hybrid strains were explored, their genomic mosaic structure caused by C. jejuni introgression was demonstrated and basic phenotypic assays were used to characterize these isolates. The genomes of the three hybrid Campylobacter strains were sequenced using PacBio SMRT sequencing, followed by methylome analysis by Restriction-Modification Finder and genome analysis by Parsnp, Smash++ and blast. Additionally, the strains were phenotypically characterized with respect to growth behaviour, motility, eukaryotic cell invasion and adhesion, autoagglutination, biofilm formation, and water survival ability. Our analyses show that the three hybrid Campylobacter strains are clade 1 C. coli strains, which have acquired between 8.1 and 9.1 % of their genome from C. jejuni. The C. jejuni genomic segments acquired are distributed over the entire genome and do not form a coherent cluster. Most of the genes originating from C. jejuni are involved in chemotaxis and motility, membrane transport, cell signalling, or the resistance to toxic compounds such as bile acids. Interspecies gene transfer from C. jejuni has contributed 8.1–9.1% to the genome of three C. coli isolates and initiated the despeciation between C. jejuni and C. coli. Based on their functional annotation, the genes originating from C. jejuni enable the adaptation of the three strains to an intra-intestinal habitat. The transfer of a fused type II restriction-modification system that recognizes the CAYNNNNNCTC/GAGNNNNNRTG motif seems to be the key for the recombination of the C. jejuni genetic material with C. coli genomes.

Evaluation of PCR assays for Campylobacter fetus detection and discrimination between C. fetus subspecies in bovine preputial wash samples

Campylobacter fetus is a zoonotic pathogen found in cattle, in which it is one of the main causes of infectious infertility. Most diagnostic laboratories use PCR as quick easy tool for C. fetus identification. However, there is no standardized PCR assay for C. fetus detection and subspecies differentiation, hindering the comparison of results. In this study, we evaluated selected PCR assays targeting the 16S rRNA, gyrB, cpn60, cstA, cdtB and nahE genes for C. fetus identification and ISCfe1, sapB2, parA and virB11 for subspecies differentiation. Analytical sensitivity and specificity were assessed for each PCR assay, and the assays were then tested on 289 bull preputial samples that had also been analysed by 16S rRNA barcode metagenomics. In total, 41 C. fetus-positive samples were included. The P12 PCR assay targeting the gyrB gene performed best, detecting the pathogen in 95.1% of positive samples. For the discrimination of C. fetus subspecies, we were able to identify a proportion (85.4%) of the C. fetus-positive samples correctly as C. fetus venerealis with at least one subspecies-specific PCR, but C. fetus fetus was not detected in any of the samples tested. Remarkably, C. fetus subspecies amplification was observed following PCR on some samples (33.1%) considered C. fetus-negative, highlighting the need for rigorous criteria for discriminating between C. fetus subspecies, to improve understanding of the role of the two C. fetus subspecies in the epidemiology and pathogenesis of bovine infectious infertility.

Characterization of Campylobacter jejuni isolated from dogs and humans using flaA-SVR fragment sequencing in Ismailia, Egypt

INTRODUCTION

Dogs are known as asymptomatic carriers forCampylobacter jejuni. The number of pet dogs is increasing in Egypt in the last decade.

OBJECTIVE

This study aimed to investigate the frequency ofC. jejuni infection in dogs and humans, molecular typing of associated virulence genes, and flaA-SVR gene using sequencing.

METHODOLOGY

152 unpaired fecal swabs from dogs (n = 72) and humans (80) were examined for the presence of C. jejuni and Campylobacter 23S rRNA, and the pathogenicity genes including mapA genes, virB11, flaA, wlaN, iam, tetO, and aadA genes. Sequencing of the flaA- amplicon was also performed for the representative isolates.

RESULTS

The isolation rate ofC. jejuni was 20.8 % and 31.2 %, respectively in dogs and humans, and all isolates were tested positive for 23S rRNA and mapA genes. C. jejuni harbor virB11 and wlaN (20 %, 0%), iam (10 %, 20 %), tetO and aadA1 (40 %, both), and flaA (40 %, 20 %) in human and dog strains, respectively. The flaA-SVR sequences revealed high identity between human and dog isolates (94.8 %), but revealed 18 substitutions in the amino acid sequence, and showed that the dog and human C. jejuni were close to strains isolated from human and poultry sources.

CONCLUSION

this study demonstrated the comparative sequence analysis ofC. jejuni flaA-SVR fragment in dogs and some Egyptians, which indicated a high identity percentage between them. The results suggest that C. jejuni reservoirs dogs is an alarming public health concern and effective hygienic measures are necessary for house-holding pets to prevent C. jejuni zoonosis in Egypt's community.

Bovine and Pig Carcasses as a Source of Campylobacter in Poland: A Reservoir for Antimicrobial-Resistant Campylobacter coli

Campylobacter is one of the most common causes of foodborne bacterial infections worldwide. Why poultry has been shown to be one of the most significant sources of these bacteria, ruminants, especially cattle, are also responsible for a high number of human Campylobacter jejuni, and to a lesser extent Campylobacter coli, infections. In this study, bovine and pig carcasses in Poland were investigated for the presence of Campylobacter and for their antimicrobial resistance. A total of 204 swabs from bovine carcasses and 355 swab samples from pig carcasses were tested during 2014-2018. Campylobacter was identified in 129 (36.3%) of the pig and in 11 (5.4%) of the bovine carcasses, respectively. The pig isolates were classified as C. coli (121; 34.1%) or C. jejuni (8; 2.3%), whereas the bovine Campylobacter were identified either as C. jejuni (8; 3.9% isolates) or C. coli (3; 1.5% strains). Resistance of the isolates (n = 140) to erythromycin, ciprofloxacin, nalidixic acid, streptomycin, and tetracycline revealed that the vast majority of C. coli was resistant to streptomycin (106 isolates; 85.5%), tetracycline (97; 78.2%), nalidixic acid (90; 72.6%), and ciprofloxacin (88; 71.0%). Among C. jejuni isolates (n = 16) the resistance rates to all antibiotics were lower than in C. coli, irrespective of the origin. A total of 74 of 121 (61.2%) C. coli isolates from the pig carcasses and one of three such isolates from the bovine samples were multiresistant. Most of the C. coli (64 isolates; 85.3%) had the ciprofloxacin+nalidixic acid+streptomycin+tetracycline resistance profile. The results suggest that pig and bovine carcasses may be an underestimated reservoir of Campylobacter, especially for C. coli in pigs. The high antimicrobial resistance rates of such strains to streptomycin, quinolones, and tetracyclines highlight the need for monitoring of these bacteria in such food and food products.

Maximising Productivity and Eliminating Campylobacter in Broilers by Manipulating Stocking Density and Population Structure Using 'Biosecurity Cubes'

This study investigates the effect of stocking density and population dynamics on broiler growth rates and productivity, while further validating the ability of the biosecurity cubes (BC) to protect birds from Campylobacter. In our methodology, six BC were constructed in a commercial broiler house containing approximately 28,500 birds. During three trials, the BC were stocked at densities of 12, 14, 16, 18, 20 and 22 birds/m², with the main flock (20 birds/m²) considered the control. Periodically, 10 birds per density were weighed and examined. The Campylobacter status of the birds was monitored via faecal samples using the ISO 10272: 2017. The stocking density for maximum calculated yield was 20 (trials 1 and 2) or 22 birds/m² (trial 3), followed by 18, 16, 14 and 12. At the stocking rate of 20 birds/m², the birds in the pen grew faster than those at the same density in the main flock achieving 2 Kg 3–6 days faster. Birds in the BC were observed to be generally healthier, and in some cases, remained Campylobacter negative, even after the main flock was infected. Our results conclude that dividing the flock into sub-flocks of approximately 20 birds/m² using BC could increase productivity up to 20%, while preventing Campylobacter.

Prevalence, Characterization, and Control of Campylobacter jejuni Isolated from Raw Milk, Cheese, and Human Stool Samples in Beni-Suef Governorate, Egypt

Our study aimed to determine the prevalence of Campylobacter jejuni isolated from raw milk, cheese, and human stool samples in Beni-Suef Governorate, Egypt, and to characterize the antibiotic resistance profile and virulence genes of the isolates. An additional objective was to evaluate the effectiveness of cinnamon oil and Lactobacillus acidophilus La5 for controlling C. jejuni in cheese. A total of 200 samples of raw milk and dairy products, including 50 samples of raw milk and 150 samples of three different types of cheese were used. Fifty-three human stool samples were also collected. The samples were tested for the presence of C. jejuni using culture and molecular methods. Campylobacter spp. were isolated from 9.5% (19/200) of the raw milk and cheese samples. The highest prevalence was observed in milk samples (18%), followed by Kareish cheese (14%) and Talaga cheese (6%). In contrast, C. jejuni was not found in any of the Feta cheese samples. Of the human stool samples, 21 (39.6%) were positive for C. jejuni. Of the isolates, 60-90% were highly resistant to the antimicrobial agents tested, that is, nalidixic acid, ciprofloxacin, and tetracycline. Virulent cadF and cdtA genes were detected in all isolates. As milk and dairy products are important sources of contamination, reducing the level of C. jejuni in them will lower the risk to consumers. We showed that L. acidophilus La5 was able to control C. jejuni in Kareish cheese, but cinnamon oil was less effective.