Campylobacter Lari Research Articles

Virulence and resistance genes in <i>Campylobacter spp</i> isolated from asymptomatic children at Kibera slum in Nairobi, Kenya

BACKGROUND Campylobacter spp. are among the global causes of food poisoning and harbour virulence and resistance genes which play a role in invasion and antibiotic resistance. This study aimed to detect selected resistance and virulence genes in archived Campylobacter spp. isolated from children in Kibera, Nairobi, Kenya. MATERIALS AND METHODS This was a retrospective laboratory-based cross-sectional study on archived samples of Campylobacter spp. at the Department of Public Health, Pharmacology and Toxicology, University of Nairobi. Campylobacter isolates were cultured on modified charcoal cefoperazone deoxycholate agar (mCCDA) media. The presence of selected virulence genes and resistance genes was detected by multiplex polymerase chain reaction (mPCR). STATA13 was used in data analysis. Binary logistic regression was used to ascertain the association between the genes and the Campylobacter spp. RESULTS The Campylobacter spp. under this study were Campylobacter jejuni (C. jejuni) (50%), Campylobacter coli (C. coli) (38%) and Campylobacter lari (C. lari) (12%). The virulence genes detected were cgtB 37 (25%), pldA (20%), cdtA (17%), cdtB (16%), cdtC (6%), wlaN (5%), iam (4%), ciaB (4%) and VirB11 (3%). The virulence gene waaC was not detected in any of the isolates. The resistance genes detected were TetA (42%), Tet B (26%), GyrB (18%) and GyrA (14%). CONCLUSION The study revealed the presence of various virulence and resistance genes in Campylobacter spp. isolated from children. This information could help guide the development and enhancement of guidelines for the management of Campylobacter infections.

Age-related presence and genetic diversity of Campylobacter spp. in young and adult yellow-legged gulls (Larus michahellis) in Croatia.

The epidemiology of Campylobacter species in wild birds is still poorly understood. This study describes the occurrence and genetic diversity of Campylobacter in adult and nestlings of yellow-legged gulls, highlighting differences between breeding locations. The gulls were captured in Croatia between 2021 and 2023. A cloacal swab was taken from each individual and tested for the presence of Campylobacter. Isolated Campylobacter species were genotyped using the multilocus sequence typing (MLST) method. A total of 1071 gulls were captured and sampled, of which 152 samples were identified as Campylobacter species, with Campylobacter jejuni (9.90%) being the most frequently isolated bacterium, followed by Campylobacter lari (3.36%) and Campylobacter coli (0.93%). Complete sequence type (ST) profiles were generated for 141 isolates: 100 C. jejuni, 33 C. lari, and 8 C. coli. A significant difference in the occurrence of positive Campylobacter species was found depending on the sampling sites, while both sampling site and age were significant for the occurrence of C. jejuni. Adults and nestlings showed high genetic diversity for C. jejuni and C. lari, and there were no significant differences between strains isolated from adults and nestlings or between sites, suggesting a high genotype flow in the studied gull population.

Whole-genome comparative analysis of the genetic, virulence and antimicrobial resistance diversity of Campylobacter spp. from Spain

Whole-Genome Sequencing has the potential to be an effective method for surveillance and control of foodborne diseases. This study aims to determine the genetic relatedness and prevalence of virulence-associated genes and antimicrobial resistance determinants in 135 Campylobacter jejuni, seven Campylobacter coli and three Campylobacter lari isolates from the poultry supply chain and hospital in Spain. The isolates showed a wide genetic diversity between and within species with Clonal Complex 21 the most frequent lineage found. Among species, C. jejuni showed the highest prevalence of virulence genes (287/333) in which a high occurring variability was observed in the capsule biosynthesis and transport, O-linked flagellar glycosylation and lipooligosaccharide biosynthesis loci, with a great impact of phase-variation that led to 72 different virulence gene patterns among all isolates. High prevalence (> 90 %) of blaOXA-type β-lactamase genes and mutations in DNA gyrase gene associated with fluoroquinolones resistance were observed, and at a frequency similar to the tet(O) gene in C. jejuni (93 %) and C. coli (86 %), both of which also harboured resistance determinants to aminoglycosides with a higher occurrence rate in C. coli (43 %), that was the only species in which mutations in the 23S ribosomal subunit conferring resistance to erythromycin were identified (43 %). The present study constitutes the largest genomic survey of Campylobacter isolates in Spain providing insight into the prevalence and diversity of the pathogen along the poultry supply chain in the country.

High Campylobacter diversity in retail chicken: epidemiologically important strains may be missed with current sampling methods.

Campylobacter spp. are leading bacterial gastroenteritis pathogens. Infections are largely underreported, and the burden of outbreaks may be underestimated. Current strategies of testing as few as one isolate per sample can affect attribution of cases to epidemiologically important sources with high Campylobacter diversity, such as chicken meat. Multiple culture method combinations were utilized to recover and sequence Campylobacter from 45 retail chicken samples purchased across Norwich, UK, selecting up to 48 isolates per sample. Simulations based on resampling were used to assess the impact of Campylobacter sequence type (ST) diversity on outbreak detection. Campylobacter was recovered from 39 samples (87%), although only one sample was positive through all broth, temperature, and plate combinations. Three species were identified (Campylobacter jejuni, Campylobacter coli, and Campylobacter lari), and 33% of samples contained two species. Positive samples contained 1-8 STs. Simulation revealed that up to 87 isolates per sample would be required to detect 95% of the observed ST diversity, and 26 isolates would be required for the average probability of detecting a random theoretical outbreak ST to reach 95%. An optimized culture approach and selecting multiple isolates per sample are essential for more complete Campylobacter recovery to support outbreak investigation and source attribution.

Comparison of optical density-based growth kinetics for pure culture Campylobacter jejuni, coli and lari grown in blood-free Bolton broth

Campylobacter growth kinetic parameters can be used to refine the sensitivity and efficiency of microbial growth-based methods. Therefore, the aim of this study was to construct growth curves for C. jejuni, C. coli, and C. lari in pure culture and calculate growth kinetics for each Campylobacter species in the same environmental conditions. Campylobacter jejuni, C. coli and C. lari were grown over 48 h and inoculated into 15 mL Hungate tubes (N = 3 trials per species; 5 biological replicates per trial; 3 species; 1 strain per species). Absorbance measurements were taken in 45 min intervals over 24 h. Optical density readings were plotted versus time to calculate growth kinetic parameters. C. jejuni exhibited the longest lag phase (p < 0.001) at 15 h 20 min ± 30 min, versus C. coli at 11 h 15 min ± 17 min, and C. lari at 9 h 27 min ± 15 min. The exponential phase duration was no longer than 5 h for all species, and doubling times were all less than 1h 30 min. The variation in growth kinetics for the three species of Campylobacter illustrates the importance of determining individual Campylobacter spp. growth responses for optimizing detection based on low bacterial levels. This study provides kinetics and estimates to define enrichment times necessary for low concentration Campylobacter detection.

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.

Campylobacteriosis in Poultry: A Review

Campylobacter is common in poultry, including layer and broiler chickens, geese, ducks, and turkeys. This review aimed to emphasize the prevalence of campylobacteriosis, recent poultry diagnoses, and strict prevention measures. Campylobacter species colonize the intestines of poultry and waterfowl but are generally nonpathogenic in poultry. However, they are the most common bacterial cause of sporadic human enteritis in both developed and developing countries. The main species responsible for campylobacteriosis is Campylobacter jejuni, followed by Campylobacter coli. A number of other Campylobacter species, such as Campylobacter lari, fetus, upsaliensis, and hyointestinalis are rarely associated with campylobacteriosis. Campylobacter hepaticus is the species linked to spotty liver disease in layers and breeder chickens, and it may be the etiological agent of the disease previously known as avian vibrionic hepatitis. The most prevalent infection source for Campylobacter is environmental contamination from poultry droppings. However, some Campylobacter species can be transmitted vertically, either on the surface of eggs or via trans-ovarian transmission in addition to consumption of contaminated feed or water. Due to the non-specific clinical signs such as diarrhea and weight loss, diagnosing campylobacteriosis in poultry requires culture or polymerase chain reaction tests. Little is known about the available vaccine or effective antibiotic treatment due to the rapid development of antibiotic resistance. Therefore, strict biosecurity measures play a crucial role in preventing Campylobacter infection in commercial poultry. These measures include decontaminating housing between flocks, preventing the entry of rodents, wild birds, and animals, and eradicating insects. To control campylobacteriosis and reduce infection risks, it is important to implement efficient on-farm biosecurity measures, conduct regular inspections of workers at meat processing plants and poultry farms, and ensure thorough preparation of chicken meat and eggs before consumption. These measures are vital in minimizing the Campylobacter transmission from both broiler and laying chickens, thereby reducing the risk of foodborne diseases caused by contaminated food.

Effects of DNA extraction methods on the real time PCR quantification of Campylobacter jejuni, Campylobacter coli, and Campylobacter lari in chicken feces and ceca contents

Polymerase chain reaction (PCR) method was coupled with a DNA extraction to enumerate Campylobacter spp. from poultry gastrointestinal tract samples. Three experiments were conducted that included: 1) Development of a DNA standard curve related to bacterial DNA primers; 2) Design of a cell/genomic DNA extraction protocol to isolate Campylobacter spp. DNA from complex samples such as poultry feces; and 3) Comparison of PCR quantification to standard plate count methodology. The standard curve using primers for Campylobacter spp. was created for DNA extracted from environmental isolates with a linear range (R2 > 0.95) and with a high specificity for C. coli and C. jejuni recovered from poultry, swine and laboratory isolates. A 2-step extraction process of bacterial DNA from poultry feces was developed in which the cells were first concentrated using a gradient-centrifugation step followed by comparison of 4 DNA extraction methods. Two commercial DNA extraction methods (Zymo Research Quick DNA, and Invitrogen magnetic separation), a traditional phenol-chloroform DNA extraction method using proteinase K to inactivate DNAses, and an in-house isolation method for DNA extraction based on chaotropic salts were used. The middle gradient layer recovered 89% to 98% of the bacteria cells from the sample, with recovery dependent upon the Campylobacter genus. The 4 DNA extractions methods recovered 112 to 302 ug/nL of DNA. Finally, the qPCR and standard plate methods were highly correlated for enumerating Campylobacter spp. in the 2.0 to 8.0-log CFU range. Analyses of the results from this study demonstrate that the combination of the standard curve for Campylobacter spp. DNA primers, the gradient cell concentration method and DNA extraction techniques with qPCR can be used to enumerate Campylobacter spp. from poultry samples with findings similar those of traditional plate count methodology.

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.

Eurasian griffon vultures carry widespread antimicrobial resistant Salmonella and Campylobacter of public health concern

The global emergence of antimicrobial-resistant (AMR) strains of Salmonella and Campylobacter is a serious public health concern. Both bacteria are leading causes of human gastrointestinal foodborne infections and the two most reported zoonoses in the European Union. By feeding on livestock carcasses, especially from intensive farming, as well as on landfill sites, obligate avian scavengers can become infected with zoonotic pathogens and AMR strains, and can be considered large-scale sentinels of the environmental burden. In this study, we assessed the occurrence and AMR of Salmonella spp. and Campylobacter spp. in 218 Eurasian griffon vultures (Gyps fulvus) captured in north-eastern Spain. We isolated Salmonella from 8.1 % of individuals and Campylobacter lari from 4.7 %. Among the 10 different Salmonella serovars found, monophasic S. Typhimurium was the most frequent. Genotyping analysis revealed same strains of monophasic S. Typhimurium shared by gulls, livestock and humans. Isolates from both bacterial species presented AMR to important antimicrobials (tetracyclines, fluoroquinolones and β-lactams). In conclusion, this study shows that Eurasian griffon vultures in north-eastern Spain are carriers of widespread AMR zoonotic Salmonella and Campylobacter. More comprehensive analyses are still needed to understand the potential risk of spill-over from those wild birds to humans.

The Role of Substrate Mediated Allostery in the Catalytic Competency of the Bacterial Oligosaccharyltransferase PglB.

The oligosaccharyltransferase of Campylobacter lari (PglB) catalyzes the glycosylation of asparagine in the consensus sequence N-X-S/T, where X is any residue except proline. Molecular dynamics simulations of PglB bound to two different substrates were used to characterize the differences in the structure and dynamics of the substrate-enzyme complexes that can explain the higher catalytic efficiency observed for substrates containing threonine at the +2 position rather than serine. We observed that a threonine-containing substrate is more tightly bound than a serine-containing substrate. Because serine lacks a methyl group relative to threonine, the serine-containing peptide cannot stably form simultaneous van der Waals interactions with T316 and I572 as the threonine-containing substrate can. As a result, the peptide-PglB interaction is destabilized and the allosteric communication between the periplasmic domain and external loop EL5 is disrupted. These changes ultimately lead to the reorientation of the periplasmic domain relative to the transmembrane domain such that the two domains are further apart compared to PglB bound to the threonine-containing peptide. The crystal structure of PglB bound to the peptide and a lipid-linked oligosaccharide analog shows a pronounced closing of the periplasmic domain over the transmembrane domain in comparison to structures of PglB with peptide only, indicating that a closed conformation of the domains is needed for catalysis. The results of our studies suggest that lower enzymatic activity observed for serine versus threonine results from a combination of less stable binding and structural changes in PglB that influence the ability to form a catalytically competent state. This study illustrates a mechanism for substrate specificity via modulation of dynamic allosteric pathways.

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

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

Establishment of sentinel surveillance of human clinical campylobacteriosis in Ireland.

The aim of this work was the establishment of a national laboratory sentinel surveillance service for human clinical Campylobacter in Ireland. This included detailed genomic molecular epidemiology of Campylobacter for 2019. For February-December 2019, 24 clinical microbiology laboratories in Ireland submitted all PCR/culture-positive clinical Campylobacter spp. specimens to Public Health Laboratory (PHL) Dublin oneweek out of every four. Antimicrobial susceptibility testing (AST) according to European Committee on Antimicrobial Susceptibility Testing (EUCAST) criteria was carried out for Campylobacter spp. isolates for ciprofloxacin, tetracycline and erythromycin. Batch whole genome sequencing (WGS) was carried out on cultures and analysis was performed to determine species, genotype, identify antimicrobial resistance (AMR) and virulence determinants and identify clusters. A total of 75 isolates and 366 PCR-positive stools were received, and 277 isolates recovered (55.7% recovery from stools). Of 257 isolates characterized by WGS, 86.4% (n=222) were Campylobacter jejuni, 11.7% (n=30) Campylobacter coli and 1.9% (n=5) Campylobacter lari. There were 20 clonal complexes with ST-21 clonal complex most prevalent at 26.8% (n=69). 50.5% (n=140) of isolates were susceptible to all three antimicrobials tested. 39.3% (n=109) isolates were ciprofloxacin resistant, 26.3% (n=73) tetracycline resistant and two isolates erythromycin resistant. Congruence between phenotypic and genotypic AST was observed. There was 95.9% and 95.6% sensitivity and specificity for WGS to predict ciprofloxacin sensitivity and 98.6% and 99.5% sensitivity and specificity for WGS to predict tetracycline sensitivity. Virulence factors flaA, racR, ciaB and cdtB were detected in all isolates. WGS identified 31 potential clusters for public health alert. This sentinel surveillance of human campylobacteriosis in Ireland establishes the basis for a national reference service. Linking with other partners in a 'One Health' framework will help us better understand sources of infection to reduce disease burden and the threat of AMR.

Multidrug-resistant Campylobacter jejuni, Campylobacter coli and Campylobacter lari isolated from asymptomatic school-going children in Kibera slum, Kenya.

Background: The objective of this study was to determine the prevalence of thermophilic Campylobacter spp. in asymptomatic school-going children and establish the antibiotic resistance patterns of the isolates towards the drugs used to treat campylobacteriosis, including macrolides, quinolones and tetracycline. Campylobacter spp. are a leading cause of enteric illness and have only recently shown resistance to antibiotics. Methods: This study isolated Campylobacter spp., including Campylobacter coli, Campylobacter jejuni and Campylobacter lari, in stool samples from asymptomatic school-going children in one of the biggest urban slums in Kenya. The disc diffusion method using EUCAST breakpoints was used to identify antibiotic-resistant isolates, which were further tested for genes encoding for tetracycline resistance using primer-specific polymerase chain reaction. Results: In total, 580 stool samples were collected from 11 primary schools considering both gender and age. Subjecting 294 biochemically characterized Campylobacter spp. isolates to genus-specific PCR, 106 (18.27% of stool samples) isolates were confirmed Campylobacter spp. Out of the 106 isolates, 28 (4.83%) were Campylobacter coli, 44 (7.58%) were Campylobacter jejuni while 11 (1.89%) were Campylobacter lari. Campylobacter jejuni had the highest number of isolates that were multi-drug resistant, with 26 out of the 28 tested isolates being resistant to ciprofloxacin (5mg), nalidixic acid (30mg), tetracycline (30mg) and erythromycin (15mg). Conclusions: In conclusion, asymptomatic school going children in the study area were found to be carriers of multidrug resistant Campylobacter coli, Campylobacter jejuni and Campylobacter lari at 84%. A one-health approach, which considers overlaps in environment, animals and human ecosystems, is recommended in addressing multidrug resistane in Campylobacter, since animals are the main reservoirs and environmental contamination is evident.

Campylobacter taeniopygiae sp. nov., Campylobacter aviculae sp. nov., and Campylobacter estrildidarum sp. nov., Novel Species Isolated from Laboratory-Maintained Zebra Finches.

Zebra finches (Taeniopygia guttata) are laboratory animal species commonly used for modeling neurobiology and learning. Historically, using bacterial culture, biochemical analysis, and 16S ribosomal RNA gene sequencing, bacterial isolates from feces of finches housed at Massachusetts Institute of Technology had been presumptively diagnosed as Campylobacter jejuni, which is commonly isolated from both domestic and wild birds. Although the zebra finches were not clinically affected, C. jejuni is a known zoonotic pathogen that causes gastroenteritis in humans worldwide. Human transmission is predominantly foodborne and associated with the consumption of contaminated poultry; however, humans can also become infected from contact with C. jejuni-infected reservoir hosts. Because C. jejuni-infected finches pose a risk to research personnel, a study was undertaken to investigate the prevalence and taxonomic identification of Campylobacter spp. present in the finch colony. Campylobacter spp. were isolated from a total of 26 finch fecal samples collected in 2003, 2010, and 2017. 16S ribosomal RNA sequencing of all isolates determined that they shared 99% identity with either C. jejuni or Campylobacter lari. Sixteen of the isolates were subjected to further biochemical characterization and atpA and rpoB gene sequence analysis. Based on these analyses, three clusters of Campylobacter species were identified. The draft whole-genome sequences were determined for one representative isolate from each cluster. A pan-genomic phylogenetic tree, average nucleotide identity, digital DNA-DNA hybridization, and orthologous gene analyses indicated that each isolate was its own novel species, distinct from C. jejuni and other avian Campylobacter species. We have named these novel species Campylobacter taeniopygiae, Campylobacter aviculae, and Campylobacter estrildidarum, and in each novel species, we identified virulence genes suggesting their pathogenic and zoonotic potential.

Complete genome sequence and comparative genomic analysis of hyper-aerotolerant Campylobacter lari strain SCHS02 isolated from duck for its potential pathogenicity

Campylobacter lari strain SCHS02, a novel hyper-aerotolerant strain that survives under aerobic conditions, was isolated from retail duck meat. The genome is a single chromosome of 1,520,838 base pairs, with a mean GC content of 29.7%. It harbors 1546 protein-coding sequences and 45 tRNA and 9 rRNA genes. Genes associated with the oxidative stress response, including perR, bcp, ahpC, and sodB, were identified in the genome. Furthermore, 68 virulence-related genes were identified and sorted into 9 classes and 14 subclasses. The virulence gene profile of SCHS02 was similar to those of two human clinical C. lari isolates. Comparative genomic analysis of strain SCHS02 and 18 C. lari strains retrieved from a public database revealed the core and accessory gene profiles of C. lari strains, as well as putative core gene involved in halotolerance. Phylogenetic analysis revealed that strain SCHS02 is genetically related to isolates from bird samples and human clinical isolates, rather than to isolates from other environmental sources. These findings reveal essential genomic information about the newly identified hyper-aerotolerant C. lari strain isolated from a duck source, providing a basis for future studies of the strain considering its potential threat to public health and further research of the pathogenicity of C. lari.

English

Campylobacter is a major agent of gastroenteritis worldwide. The incidence and prevalence of campylobacteriosis have been increasing in both developed and developing countries over the last decade. In this study, 197 strains of successive Campylobacter-like were identified in French laboratories in September 2018. Bacterial isolates from clinical samples were identified with a mass spectrometer (Ultraflex III TOF/TOF and the BIOTYPER database from Bruker Daltonics). Of the 197 isolates tested, 143 were identified as Campylobacter jejuni (72.59%), 28 as Campylobacter coli (14.21%), 2 as Arcobacter butzleri (1.02%), 1 as Campylobacter fetus and 1 as Campylobacter lari with (0.51% each) by the MALDI-TOF mass spectrometry. Isolation rate of Campylobacter was highest in the 0 - 9 age group (22%). The proportion of male and female patients was 59.4% (CI 95% = 52.2-66.3) and 40.6% (CI 95% = 33.7-42.8) respectively. Sixty strains (30.5%) were resistant to tetracycline and 52 (26.4%) resistant to ampicillin. This study showed that the MALDI-TOF mass spectrometry is a rapid and accurate identification method of Campylobater spp in patients treated in private French laboratories. Key words: Campylobacter, identification, MALDI-TOF, patients, France.

Multidrug-resistant Campylobacter jejuni, Campylobacter coli and Campylobacter lari isolated from asymptomatic school-going children in Kibera slum, Kenya

Background:The objective of this study was to determine the prevalence of thermophilicCampylobacterspp. in asymptomatic school-going children and establish the antibiotic resistant patterns of the isolates towards the drugs used to treat campylobacteriosis, including macrolides, quinolones and tetracycline.Campylobacterspp. are a leading cause of enteric illness and have only recently shown resistant to antibiotics.Methods:This study isolatedCampylobacterspp., includingCampylobacter coli,Campylobacter jejuniandCampylobacter lari, in stool samples from asymptomatic school-going children in one of the biggest urban slums in Kenya. The disc diffusion method using EUCAST breakpoints was used to identify antibiotic-resistant isolates, which were further tested for genes encoding for tetracycline resistances using primer-specific polymerase chain reaction.Results:In total, 580 stool samples were collected from 11 primary schools considering both gender and age. Subjecting 294 biochemically characterizedCampylobacterspp. isolates to genus-specific PCR, 106 (18.27% of stool samples) isolates were confirmedCampylobacterspp. Out of the 106 isolates, 28 (4.83%) wereCampylobactercoli, 44 (7.58%) wereCampylobacter jejuniwhile 11 (1.89%) wereCampylobacterlari.Campylobacter jejunihad the highest number of isolates that were multi-drug resistant, with 26 out of the 28 tested isolates being resistant to ciprofloxacin (5 mg), nalidixic acid (30 mg), tetracycline (30 mg) and erythromycin (15 mg).Conclusions:In conclusion, a one-health approach, which considers overlaps in environment, animals and human ecosystems, is recommended in addressing campylobacteriosis in humans, since animals are the main reservoirs and environmental contamination is evident.

Campylobacter lari associated Prosthetic Joint Infection

Campylobacter lariis a rare cause of extraintestinal infection in humans. There has only been one prior case report of prosthetic joint infection in an immunocompetent adult, which was rapidly fatal. We can identify no previous case reports of successful management of this condition. We discuss our management of a 63 year old stable manager that presented with 1 week history of right prosthetic knee pain and swelling. Following two washouts the patient underwent a first-stage revision of his knee. Post-operative antibiotic choice was empirical, and 28-day outcome has been promising, with complete resolution of inflammatory markers and resolution of symptoms. Outcome following planned second-stage revision will be discussed at FIS 2019.

Campylobacter armoricus sp. nov., a novel member of the Campylobacter lari group isolated from surface water and stools from humans with enteric infection.

During a study on the prevalence and diversity of members of the genus Campylobacter in a shellfish-harvesting area and its catchment in Brittany, France, six urease-positive isolates of members of the genus Campylobacter were recovered from surface water samples, as well as three isolates from stools of humans displaying enteric infection in the same period. These strains were initially identified as members of the Campylobacter lari group by MALDI-TOF mass spectrometry and placed into a distinct group in the genus Campylobacter, following atpA gene sequence analysis based on whole-genome sequencing data. This taxonomic position was confirmed by phylogenetic analysis of the 16S rRNA, rpoB and hsp60 (groEL) loci, and an analysis of the core genome that provided an improved phylogenetic resolution. The average nucleotide identity between the representative strain CA656T (CCUG 73571T=CIP 111675T) and the type strain of the most closely related species Campylobacter ornithocola WBE38T was 88.5 %. The strains were found to be microaerobic and anaerobic, motile, non-spore-forming, Gram-stain-negative, spiral-shaped bacteria that exhibit catalase, oxidase and urease activities but not nitrate reduction. This study demonstrates clearly that the nine isolates represent a novel species within the C. lari group, for which the name Campylobacter armoricus is proposed. Here, we present phenotypic and morphological features of the nine strains and the description of their genome sequences. The proposed type strain CA656T has a 1.589 Mbp chromosome with a DNA G+C content of 28.5 mol% and encodes 1588 predicted coding sequences, 38 tRNAs, and 3 rRNA operons.