Thermophilic Campylobacter Research Articles

Development and Evaluation of Fluorescence Immunochromatography for Rapid and Sensitive Detection of Thermophilic Campylobacter.

Campylobacter jejuni (C. jejuni) and Campylobacter coli (C. coli) are leading causes of foodborne gastroenteritis in Japan. Epidemiological surveillance has provided evidence that poultry meat is one of the main reservoirs for human campylobacteriosis, and therefore, improvement in process hygiene at slaughter is required to reduce the number of human infections. This study thus aimed to develop fluorescent immunochromatography strips for rapid and sensitive detection of thermophilic Campylobacter on poultry carcasses at slaughter. To establish the required detection levels, we first determined the numbers of C. jejuni and C. coli on poultry carcasses at one large-scale poultry slaughterhouse in Japan, resulting in the detection of Campylobacter at 1.97 ± 0.24 log CFU/25 g of neck skin during the post-chilling process by using ISO 10272-2:2017. Our developed Campylobacter fluorescence immunochromatography (FIC) assay exhibited a 50% limit of detection of 3.51 log CFU or 4.34 log CFU for C. jejuni NCTC 11168 or C. coli JCM 2529, respectively. Inclusive and exclusive tests resulted in good agreement. The practical usefulness of this test toward poultry carcasses should be evaluated in future studies, perhaps concentration of the target microorganisms prior to the testing might be helpful to further enhance sensitivity. Nevertheless, our data suggest the potential of FIC for rapid and sensitive detection of thermophilic Campylobacter for monitoring the process hygiene of poultry carcasses at slaughter.

Antimicrobial Resistance and in silico Virulence Profiling of Aliarcobacter butzleri Strains From German Water Poultry.

Aliarcobacter butzleri is an emerging foodborne and zoonotic pathogen that is usually transmitted via contaminated food or water. A. butzleri is not only the most prevalent Aliarcobacter species, it is also closely related to thermophilic Campylobacter, which have shown increasing resistance in recent years. Therefore, it is important to assess its resistance and virulence profiles. In this study, 45 Aliarcobacter butzleri strains from water poultry farms in Thuringia, Germany, were subjected to an antimicrobial susceptibility test using the gradient strip diffusion method and whole-genome sequencing. In the phylogenetic analysis, the genomes of the German strains showed high genetic diversity. Thirty-three isolates formed 11 subgroups containing two to six strains. The antimicrobial susceptibility testing showed that 32 strains were resistant to erythromycin, 26 to doxycycline, and 20 to tetracycline, respectively. Only two strains were resistant to ciprofloxacin, while 39 strains were resistant to streptomycin. The in silico prediction of the antimicrobial resistance profiles identified a large repertoire of potential resistance mechanisms. A strong correlation between a gyrA point mutation (Thr-85-Ile) and ciprofloxacin resistance was found in 11 strains. A partial correlation was observed between the presence of the bla3 gene and ampicillin resistance. In silico virulence profiling revealed a broad spectrum of putative virulence factors, including a complete lipid A cluster in all studied genomes.

Comparison of antimicrobial resistance in thermophilic Campylobacter strains isolated from conventional production and backyard poultry flocks

ABSTRACT 1. The aim of this study was to compare the resistance pattern of thermophilic Campylobacter spp. isolated from conventional production (n = 34) and backyard poultry flocks (n = 36) from Rio de Janeiro State, Brazil. The disc diffusion method and statistical tests were used for investigation and analysis of the resistance pattern of Campylobacter spp. isolated from different rearing systems. 2. Antimicrobial resistance percentages to amoxycillin with clavulanic acid (AMC), ampicillin (AMP), ceftiofur (CTF), ciprofloxacin (CIP), enrofloxacin (ENO), erythromycin (ERI), gentamicin (GEN) and tetracycline (TET) were 32.4%, 44.1%, 67.6%, 97.1%, 82.4%, 26.5%, 5.9% and 38.2% in conventional production flocks respectively, while the backyard flock’s resistance levels were 0.0%, 13.9%, 69.4%, 100.0%, 91.7%, 5.6%, 0.0% and 16.7%, respectively. 3. Campylobacter spp. from conventional poultry production was more resistant to AMC, AMO, ERI and TET (P > 0.05) when compared to strains from backyard poultry. A higher frequency of resistance to fluoroquinolones (FLQ), CIP and ENO, was observed in strains from both systems, demonstrating the spread of resistant strains among poultry production environments.

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.

Genotyping and molecular characterization of antimicrobial resistance in thermophilic Campylobacter isolated from poultry breeders and their progeny in Eastern Spain

Thermophilic Campylobacter spp. are recognized as a major cause of acute bacterial diarrhea in humans, with broiler meat being the most common source of human infection. Antibiotic therapy is usually necessary for severe or prolonged infections, especially in immunocompromised populations such as young or elderly individuals. However, different studies have demonstrated a close association between antibiotic use in animal production and antimicrobial resistance (AMR) in humans. In this sense, there is social pressure to reduce antibiotic administration and find adequate alternatives to control the presence of bacterial infections in farms. However, there is a lack of information related to Campylobacter AMR dynamics through the entire production system from breeders to their progeny. It is unknown if resistance genes are a result of adaptation through chromosomal mutation or through horizontal gene transfer, instead of vertical transmission of DNA from the parent to their progeny. Thus, the main objectives of this study were to assess the main AMR rates present in a poultry production system, to study the relationship between Campylobacter AMR profiles from breeders and their progeny, and to study the presence and distribution of antibiotic resistance genes in poultry production. Regarding AMR rates, ciprofloxacin was classified as extremely high, followed by nalidixic acid and tetracyclines that were classified as very high. Moreover, this study demonstrated a relationship between the AMR patterns and genes found from Campylobacter strains isolated in breeders and those present in their progeny.

Underestimated Survival of Campylobacter in Raw Milk Highlighted by Viability Real-Time PCR and Growth Recovery.

Raw milk is a frequent vehicle for transmission of thermophilic Campylobacter, leading to reported outbreaks. Milk is a challenging food matrix for pathogen detection, due to its high protein and lipid content. Limited detection of Campylobacter colony-forming unit (CFU) in raw milk might underestimate the pathogen’s infectious potential. We optimized a viability real-time PCR (qPCR) for application with raw milk. The procedure was robust against variations of milk lots and different Campylobacter strains. Various DNA-intercalating dyes were evaluated for their ability to reduce the PCR signal of dead cells. Only propidium monoazide (PMA) and PMAxx qualified for diagnostic use. Different sedimentation properties of viable and dead Campylobacter jejuni and Campylobacter coli strains in 10-fold diluted milk enhanced viable/dead differentiation. The new method enabled to review survival of Campylobacter spp. in raw milk based on viable cells harboring an intact cell membrane. The data were compared to culturability according to ISO10272-2:2017. A difference of up to 4.5 log10 between viable Campylobacter counts and CFU values became apparent. Relevance of viability qPCR values was corroborated by full recovery of CFU under extremely reduced oxygen concentration in the presence of hydrogen. Recovery of CFU was limited, however, upon prolonged exposure in raw milk. The data confirm that Campylobacter survival in raw milk can be largely underestimated when relying on CFU data only. We conclude that raw milk led to oxidative stress-induced growth arrest in thermophilic Campylobacter, which was reversible by reduction of the oxygen partial pressure in a time-limited way.

Genetic diversity, antimicrobial resistance, and virulence genes of thermophilic Campylobacter isolated from broiler production chain.

The aim of this study was to investigate the prevalence of thermophilic Campylobacter in the broiler production chain of southern Brazil, by evaluating broiler farms and slaughter line samples, and to determine the genetic diversity, antimicrobial resistance, and virulence genes of the isolates. Of the 140 samples investigated in this study, 75 (53.6%) were positive for thermophilic Campylobacter, and all isolates were identified by phenotypic and molecular tests as C. jejuni. The resistance to nalidixic acid was the most common (74%), followed by resistance to enrofloxacin (67.3%) and ciprofloxacin (37.1%). However, there was no resistance to the macrolides tested which are recommended for the treatment of human campylobacteriosis. The PFGE showed that the isolates were grouped in eight macrorestriction patterns (P1 to P8). A representative isolate of each macrorestriction pattern was investigated for the presence of virulence genes and all isolates carried the cadF, ciaB, cdtA, cdtB, cdtC, and flaA genes. The dnaJ gene was detected in 87.5% (7/8) of the isolates. The flhA and racR genes were detected in 75% (6/8), while the pldA gene was present in 62.5% (5/8) and the wlaN gene in 25% (2/8). The presence of C. jejuni in broiler farms and in the slaughterhouse is a hazard to consumer given that this pathogen can be maintained throughout the broiler production chain and contaminates the final product. Moreover, the presence of the major virulence genes in the isolates demonstrates that they have the ability to develop campylobacteriosis in humans.

Antimicrobial Resistance Determinants Circulating among Thermophilic Campylobacter Isolates Recovered from Broilers in Ireland Over a One-Year Period.

Campylobacteriosis is the leading cause of human bacterial gastroenteritis, very often associated with poultry consumption. Thermophilic Campylobacter (Campylobacter jejuni and Campylobacter coli) isolates (n = 158) recovered from broiler neck skin and caecal contents in Ireland over a one-year period, resistant to at least one of three clinically relevant antimicrobial classes, were screened for resistance determinants. All ciprofloxacin-resistant isolates (n = 99) harboured the C257T nucleotide mutation (conferring the Thr-86-Ile substitution) in conjunction with other synonymous and nonsynonymous mutations, which may have epidemiological value. The A2075G nucleotide mutation and amino acid substitutions in L4 and L22 were detected in all erythromycin-resistant isolates (n = 5). The tetO gene was detected in 100% (n = 119) of tetracycline-resistant isolates and three of which were found to harbour the mosaic tetracycline resistance gene tetO/32/O. Two streptomycin-resistant C. jejuni isolates (isolated from the same flock) harboured ant(6)-Ib, located in a multidrug resistance genomic island, containing aminoglycoside, streptothricin (satA) and tetracycline resistance genes (truncated tetO and mosaic tetO/32/O). The ant(6)-Ie gene was identified in two streptomycin-resistant C. coli isolates. This study highlights the widespread acquisition of antimicrobial resistance determinants among chicken-associated Campylobacter isolates, through horizontal gene transfer or clonal expansion of resistant lineages. The stability of such resistance determinants is compounded by the fluidity of mobile genetic element.

Dogs and Cats: Reservoirs for Highly Diverse Campylobacter jejuni and a Potential Source of Human Exposure.

Simple SummaryCampylobacter is among the most common causes of bacterial gastroenteritis and is associated with post-infectious neuropathies. This organism is part of the commensal microbiota of numerous host species, including companion animals. Molecular typing approaches have been used to attribute the source of human campylobacteriosis and showed that broilers are a major infection source, while pets are a non-negligible one (10–25% of clinical cases). Since the assessment of animal colonization by Campylobacter is crucial to better understand its epidemiology, we determined the Campylobacter carriage by dogs and cats, hereafter defined as pets, and characterized genetically Campylobacter jejuni (C. jejuni) isolates. Pets appeared to frequently carry Campylobacter. The comparison of genetic profiles of C. jejuni isolates with isolates from several animal reservoirs and clinical cases revealed an overlap between profiles. These results suggest potential pets’ contamination by livestock or inversely, as well as their potential role in Campylobacter transmission to humans. However, some pets’ profiles were not isolated in livestock, which suggests the existence of other sources of pet contamination by C. jejuni or implies that pets may constitute a reservoir for Campylobacter with specific profiles. Since frequent contact occurs between pets and humans, this work emphasized the potential role of pets as a source of human exposure to Campylobacter.Assessing the carriage of Campylobacter in animal reservoirs is essential to better understand Campylobacter epidemiology. Here, we evaluated the prevalence of thermophilic Campylobacter spp. in dogs and cats, hereafter defined as pets, and characterized Campylobacter jejuni (C. jejuni) isolates to assess their genetic diversity and their potential link with isolates from other animals or human cases. During a 6-month period, 304 feces samples were collected from pets. A significantly higher prevalence of thermophilic Campylobacter spp. was found in dogs compared with cats, as well as in dogs ≤ 1-year-old compared with older dogs. C. jejuni was the predominant species found in pets, and its genomic characterization revealed a high genetic diversity. Genotypes comparison with previously characterized isolates revealed a partial overlap between C. jejuni isolates from pets, chicken, cattle, and clinical cases. This overlap suggests the potential role of livestock and humans in pets’ exposure to Campylobacter, or vice versa. The isolation of pets’ specific profiles may suggest the existence of other sources of pet contamination or imply that pets may constitute a reservoir for Campylobacter. Because of the proximity between humans and pets, along with their frequent carriage of C. jejuni, human exposure to Campylobacter from pets can be more important than previously thought.

Occurrence and antimicrobial resistance of Campylobacter jejuni isolates from poultry in Casablanca-Settat, Morocco.

Campylobacteriosis and Campylobacter spp. resistance to antibiotics represents a serious worldwide public health problem thermophilic Campylobacters, in particular, are major causes of gastroenteritis in humans. The aim of this study was to determine the prevalence and antimicrobial resistance of Campylobacter jejuni isolated from chicken droppings, of commercial poultry in the city of Casablanca, Morocco. Between February and September 2017, 140 samples of chicken droppings were collected and analyzed by classical bacteriology methods for isolation and identification according to Moroccan Standard NM ISO/TS 10272-3 (2013), followed by molecular identification (PCR: polymerase chain reaction). Among the 140 samples, 102 (73%) were positive by Campylobacter spp. tests and 38 (27.14 %) were negative to Campylobacter spp. Among the positive colonies, 41 (40, 2%) were C. jejuni. Of the 41 C. jejuni isolates, resistance was detected to tetracycline (100%), erythromycin (97%), ampicillin (85%), ciprofloxacin (77%), amoxicillin/ clavulanic acid (61.4%), and gentamicin (12.0%). In conclusion, the data obtained in the current study demonstrate that the majority of C. jejuni isolates evaluated were resistant to antimicrobials of the cycline, macrolide, and fluoroquinolone families, and all of the isolates were susceptible to gentamicin. Fluoroquinolone is the drug of choice for treating Campylobacter infections. These results underline the need for prudent use of antibiotics in poultry production to minimize the spread of antibioticresistant Campylobacter spp.

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.

MOLECULAR CHARACTERIZATION OF CAMPYLOBACTER SPECIES FROM TURKEYS FLOCKS IN DELTA GOVERNMENTS

Two hundred and forty samples were collected from turkey farms and various markets in Delta Governorates for Campylobacter spp. isolation. Multiplex PCR assay was used to identify 2 Thermophilic Campylobacter species (C. jejuni and C. coli). The prevalence of Campylobacter in turkeys(22.5%) observed in this study; C. jejuni was 15.4% and C. coli 7%. The high incidence of Campylobacter in liver was (30%) followed by skin (26.7%), cloacal swabs (21.3%) and finally intestinal content (16.7%). A food borne disease infected with campylobacteriosis resulting from consuming or handling of contaminated poultry meat. The high incidence of Campylobacter due to contamination to intestinal tract during evisceration can lead to direct contamination of the carcasses or indirectly through the hands of the processors, material or instrument used in processing. The amplification of the DNA belonging to Campylobacter genus specific (C. jejuni hipO) was (19%); (13.8%) C. jejuni at 323 bp and (5.8%) C. coli at 126 bp, while for C. jejuni 23S rRNA at 650 bp. PCR analysis for detection of Campylobacter can be utilized as a simple, rapid and sensitive tool to discriminate stains recovered from different sources, especially when used as profile analysis for a control strategy of C. jejuni in turkey farms to reduce the risk of human exposure to Campylobacter and is an important food safety issue. Multiplex PCR was found to be more reliable than the conventional cultural methods in species level for identification of Campylobacter isolates. Further epidemiological studies at different geographical areas, carried to discover the prevalence, magnitude and importance of Campylobacter infection in turkey farms.

Prevalence, Risk Factors, and Antimicrobial Resistance Profiles of Thermophilic Campylobacter Species in Humans and Animals in Sub-Saharan Africa: A Systematic Review.

Thermophilic Campylobacter species are clinically important aetiologies of gastroenteritis in humans throughout the world. The colonization of different animal reservoirs by Campylobacter poses an important risk for humans through shedding of the pathogen in livestock waste and contamination of water sources, environment, and food. A review of published articles was conducted to obtain information on the prevalence and antimicrobial resistance (AMR) profiles of thermophilic Campylobacter species in humans and animals in sub-Saharan Africa (SSA). Electronic databases, namely, PubMed, Google Scholar, Research4life-HINARI Health, and Researchgate.net, were searched using the following search terms “thermophilic Campylobacter,” “Campylobacter jejuni,” “Campylobacter coli,” “diarrhea/diarrhoea,” “antimicrobial resistance,” “antibiotic resistance,” “humans,” “animals,” “Sub-Saharan Africa,” and “a specific country name.” Initially, a total of 614 articles were identified, and the lists of references were screened in which 22 more articles were identified. After screening, 33 articles on humans and 34 on animals and animal products were included in this review. In humans, Nigeria reported the highest prevalence (62.7%), followed by Malawi (21%) and South Africa (20.3%). For Campylobacter infections in under-five children, Kenya reported 16.4%, followed by Rwanda (15.5%) and Ethiopia (14.5%). The country-level mean prevalence in all ages and under-five children was 18.6% and 9.4%, respectively. The prevalence ranged from 1.7%–62.7% in humans and 1.2%–80% in animals. The most reported species were C. jejuni and C. coli. The AMR to commonly used antimicrobials ranged from 0–100% in both humans and animals. Poultry consumption and drinking surface water were the main risk factors for campylobacteriosis. The present review provides evidence of thermophilic Campylobacter occurrence in humans and animals and high levels of AMR in SSA, emphasizing the need for strengthening both national and regional multisectoral antimicrobial resistance standard surveillance protocols to curb both the campylobacteriosis burden and increase of antimicrobial resistance in the region.

The Prevalence of Virulence Genes and Multidrug Resistance in Thermophilic Campylobacter Spp. Isolated from Dogs.

The aim of the study was to determine the role of dogs as a potential reservoir of Campylobacter spp. At the next stage of the research the frequency of occurrence of selected virulence genes, i.e. cadF, flaA and iam as well as genes responsible for the formation the cytolethal distending toxin (CDT), i.e. cdtA, cdtB and cdtC was determined. The isolates obtained in the research were tested for their resistance to selected antibiotics: ciprofloxacin (CIP), enrofloxacin (EF), erythromycin (E) and tetracycline (TE). Campylobacter spp. was found in 63 (12.6%) out of a total number of 500 isolates. 61 (12.2%) isolates were identified as C. jejuni. The number of C. jejuni isolates found in the younger animals was smaller (p <0.05) than in the older ones. The frequency of occurrence of virulence genes and the genes responsible for the formation of CDT was significantly (p <0.05) higher in the older dogs. A comparison of the effect of antibiotics showed that the isolates obtained from both age groups exhibited low resistance to erythrosine (13.5% in the group aged under 1 year and 8.6% in the group aged over 1 year). Both groups exhibited the highest resistance to ciprofloxacin and enrofloxacin.

Recovery of thermophilic Campylobacter by three sampling methods from river sites in Northeast Georgia, USA, and their antimicrobial resistance genes.

Sixteen sites in the watershed of the South Fork of the Broad River (SFBR) in Northeastern Georgia, USA, were sampled in two seasons to detect Campylobacter. Sites were classified as mostly influenced by forest, pasture, wastewater pollution control plants (WPC) or mixed use. Sampling was repeated in the late spring and late fall for 2years for a total of 126 samples. Free-catch water and sediment grab samples were taken at each site; Moore's swabs were placed for up to 3days at most sites. A total of 56 isolates of thermophilic Campylobacter were recovered. Thirteen samplings were positive by two or three methods, and 26 samplings were positive by only one method; once by Moore's swab only and 25 times by free-catch water only. Campylobacter was detected at 58% of cattle pasture sites, 30% of forested sites and 81% of WPC sites. Twenty-one of the isolates carried antimicrobial resistance genes, mostly blaOXA-61. Free-catch water samples were more efficient than Moore's swabs or sediment samples for recovery of Campylobacter, which was more likely to be detected in streams near cattle pastures and human communities than in forested land. SIGNIFICANCE AND IMPACT OF THE STUDY: The role of environmental water in transmitting Campylobacter was investigated, and methods for recovery of the organism were compared. The sequence types of recovered Campylobacter correlated with adjacent land use without regard to the method used to isolate the organisms. Sequence types and antimicrobial resistance genes associated with cattle were most prevalent near pastures. Even though types were recurrent at a given site, types appeared to be lost or replaced as the water flowed downstream.

Multilocus Sequence Typing (MLST) of Campylobacter jejuni Isolated From Broiler Meat in Egypt.

Infection with Campylobacter jejuni is one of the most common causes of bacterial gastroenteritis. Infections are mostly acquired due to consumption of raw or undercooked poultry. The aim of this pilot study is to determine the prevalence and the sequence types (STs) distribution of C. jejuni isolated from broiler meat in Egypt. A total of 190 broiler meat samples were collected from retail chicken shops located at Mansoura, Egypt and examined bacteriologically for the presence of Campylobacter spp. The biochemically identified Campylobacter isolates were confirmed by Multiplex PCR (m-PCR). In addition, multilocus sequencing typing (MLST) was used for genotyping of C. jejuni isolates. Thirty two Campylobacter isolates divided into C. coli (25 isolates) and C. jejuni (7 isolates) were recovered. Multiplex PCR results found to be 100% in line with biochemical identification. Out of 7 C. jejuni isolates genotyped by MLST, 4 isolates were assigned to ST21, 2 isolates were assigned to ST48 and one isolate was assigned to ST464. This study provides valuable information concerning the prevalence of thermophilic Campylobacter spp. and sequence types distribution of C. jejuni recovered from broiler meat for the first time in Egypt. The identified sequence types from this study were frequently reported in human illnesses. Thus, the present results highlight the importance of the retail broiler meat as a significant source for human Campylobacter infection.

Detection of virulent thermophilic Campylobacter species in communal chickens

Campylobacter is a foodborne pathogen found in the gut of poultry and other animals, which thereby act as reservoirs for human infection. Campylobacter produces various virulence factors which contribute to the establishment of disease. The aim of this study was to detect virulence genes in Campylobacter isolated from chicken faeces. A total of 408 poultry cloacal samples were analysed through culture, PCR and DNA sequencing. Campylobacter were detected in 24 (5.9 %) of the samples, of which 21 were C. jejuni while 3 were C. coli. The cdtB gene was detected in all Campylobacter isolates while cdtA and cdtC genes were detected in 20 (83.3%) and 18 (75.0%) of the isolates, respectively. The cadF gene was detected in 18 (85.7%) C. jejuni but not in C. coli. Eight genotypes designated G1 to G8 were detected among the isolates. Genotypes G1 and G7 possessed all three cdt genes, a potential for producing functionally active toxins. A large proportion (70.8%) of the isolates possessed both genes for toxin production and adhesion. The high prevalence of cdt and cadF genes in Campylobacter species in this study indicates the pathogenic potential of the isolates. There is a need to implement control measures to curb the spread of these virulent strains.&#x0D; Significance:&#x0D; &#x0D; Virulent thermophilic campylobacters cause severe health complications in humans.&#x0D; Although chicken meat is the main source of human infections, there is limited data on the occurrence of Campylobacter in chicken faeces in southern Africa.&#x0D; This study adds to literature on the occurrence of virulent strains of Campylobacter species, notably through the deposition of the DNA sequences of our local strains into GenBank®.&#x0D; Communal chickens may serve as a source of virulent thermophilic campylobacters to humans, resulting in serious public health implications.&#x0D; &#x0D; Open data sets: &#x0D; MF872608 - https://www.ncbi.nlm.nih.gov/nuccore/MF872608.1 MF872609 - https://www.ncbi.nlm.nih.gov/nuccore/MF872609.1MF872610 - https://www.ncbi.nlm.nih.gov/nuccore/MF872610.1MF872611 - https://www.ncbi.nlm.nih.gov/nuccore/MF872611.1MF872612 - https://www.ncbi.nlm.nih.gov/nuccore/MF872612.1

Overlap of Antibiotic Resistant Campylobacter jejuni MLST Genotypes Isolated From Humans, Broiler Products, Dairy Cattle and Wild Birds in Lithuania.

Antimicrobial resistance was determined for 341 thermophilic Campylobacter jejuni isolates obtained from human clinical cases (n = 101), broiler products (n = 98), dairy cattle (n = 41) and wild birds (n = 101) with known multilocus sequence types (MLST) in Lithuania. The minimum inhibitory concentration (MIC) values for ciprofloxacin, tetracycline, gentamicin, ceftriaxone and erythromycin were determined with the agar dilution method. MIC values were compared with MLST types to find possible associations among isolation source, sequence type and resistance to antibiotics. The proportions of resistant strains were 94.2% (human), 95% (wild birds), 100% (broiler products) and 100% (dairy cattle) for one of the tested antibiotics. Most frequently, resistance to ciprofloxacin was observed (91.5%), followed by ceftriaxone with 60.4%, and tetracycline (37.8%). However only three C. jejuni strains were resistant to erythromycin (0.9%) and all tested thermophilic Campylobacter strains were sensitive to gentamicin. Most of the examined C. jejuni isolates (80.6%) showed resistance to at least one of three profiles: CIP+AXO (28.1%), TET+CIP+AXO (26.7%) and CIP (25.8%). Statistically significant differences in resistance to tetracycline were found between C. jejuni strains obtained from cattle (85.4%) and broiler products (64.3%) (P < 0.05). The majority (87.1%) of the tested strains from wild birds were resistant to ciprofloxacin (P < 0.05). The results showed that strains of novel ST’s showed significantly lower resistance to ceftriaxone (P < 0.05). The ST-21 (CC21) (78.8%) was identified with significantly higher multidrug resistance relatively to other tested ST’s in this study. Our results emphasize the high antimicrobial resistance of phylogenetically diverse C. jejuni strains isolated from different sources including specific genotypes of wild bird’s strains in Lithuania. The results support the opinion that not only broiler products but cattle and wild birds may be a reservoir of resistant C. jejuni and stipulate a risk of spread or resistant bacteria. There is increasing need for broad surveillance and control measures to track changes and pathways of antimicrobial resistance of C. jejuni in epidemiologically distinct populations.

A review of the novel thermophilic Campylobacter, Campylobacter hepaticus, a pathogen of poultry.

In 2015, a novel thermophilic Campylobacter was isolated from cases of spotty liver disease in laying hens in the UK. In 2016, it was isolated from laying hens in Australia where it was formally named Campylobacter hepaticus and confirmed as the cause of spotty liver disease. It has also been isolated from laying hens in America. It is fastidious, grows slowly on first isolation and does not grow on media used to routinely isolate Campylobacter. Spotty liver disease is an acute, randomly distributed, focal, necrotic hepatitis causing mortality in up to 10% of a flock and a 10%-15% fall in egg production. It occurs mainly in free-range hens or hens reared on the ground at around the time of peak lay. The incidence of the disease has increased in countries where there is an increase in keeping free-range laying hens. It is similar to the condition avian vibrionic hepatitis which was reported in America, Europe and Australasia in the 1950s to 1970s and the agent isolated from cases of avian vibrionic hepatitis and C.hepaticus appear to be very similar. It is not known if C.hepaticus is zoonotic but whole genome sequencing shows that it is most closely related to the known zoonotic campylobacters Campylobacter jejuni and Campylobacter coli. Human exposure to C.hepaticus is likely through similar exposure routes. Analysis of the whole genome showed a reduction in the genes for iron metabolism compared to C.jejuni. A requirement for iron was confirmed as it showed reduced growth in an iron depletion assay and this may explain its tissue tropism. With a move towards free-range egg production in many countries, the incidence of C.hepaticus hepatitis is likely to increase, but the identification of the causal agent will provide opportunities for the development of control methods.

Prevalence, antimicrobial resistance profiles and virulence-associated genes of thermophilic Campylobacter spp. isolated from ducks in a Chinese slaughterhouse

A total of 220 Campylobacter isolates was recovered from 656 samples along a commercial duck slaughter line after a panel of confirmation tests including selective culture methods, biochemical identification and multiplex PCR in southwestern China. The prevalence of Campylobacter spp. was 33.5%, including 16.6% of Campylobacter jejuni, 15.7% of Campylobacter coli and 3.6% of other Campylobacter species. A high level of resistance was observed to tetracycline (96.4%) and clindamycin (92.3%), followed by azithromycin (66.8%), erythromycin (47.3%), nalidixic acid (44.5%), chloramphenicol (42.7%), gentamicin (41.4%), and ciprofloxacin (37.3%). Forty-seven classes of antimicrobial resistance profile were found, and multidrug resistant (MDR) strains occupied 75.9% of the Campylobacter isolates. Virulence-associated genes of cadF (100%), cheY (92.7%) and cdtB (92.3%) were commonly observed in the Campylobacter isolates, followed by flaA (77.2%), iamA (71.8%), cdtA (60%), cdtC (54.1%) and ciaB (42.7%). Virulence gene of virB11 (7.7%) was less frequently detected. Totally, 48 virulence gene profiles were generated among Campylobacter isolates. Our results confirmed the prevalence of Campylobacter spp. in the duck slaughterhouse, which were MDR and harbored several putative virulence-associated genes that might pose harm to human.