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result(s) for
"Campylobacter coli - pathogenicity"
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Prevalence and antimicrobial resistance of Campylobacter jejuni and Campylobacter coli isolated from children and environmental sources in urban and suburban areas
by
Spica, Dorota
,
Klawe, Jacek J.
,
Andrzejewska, Małgorzata
in
Agar
,
Animals
,
Anti-Bacterial Agents - pharmacology
2017
Background
Campylobacteriosis is a dominant bacterial cause of foodborne infection and is considered the main public health problem in Europe and many other countries worldwide. In the study lasting from 2011 to 2013 we compared the prevalence and antimicrobial resistance of
Campylobacter jejuni
and
Campylobacter coli
isolated from children, domestic animals, poultry meat and surface water in Northern Poland.
Results
During a 3-years study 1973 samples were analysed. The results proved the presence of
Campylobacter
spp. in 306 (15.5%) samples. The percentage of
Campylobacter
-positive samples differed among the sample types, from 0% (freshwater beaches) to 38.6% (poultry meat in 2011). Prevalence of
Campylobacter
spp. in children isolates was 9.6%. It decreased from 13.2% in 2011 to 8.0% in 2013. It should be highlighted with a particular concern that
Campylobacter jejuni
was detected in 20.0% of fountains. All children and poultry meat isolates were susceptible to azithromycin. Two
C. coli
(3.7%) and four
C. jejuni
(3.3%) isolated from poultry meat were resistant to erythromycin. The highest percentage of
C. jejuni
isolates with resistance to ciprofloxacin were found in samples from 80% dogs and 85% ponds. Among isolates resistant to two antimicrobials 74.7%
C. jejuni
and 59.2%
C. coli
isolates were resistant to ciprofloxacin as well as to tetracycline. Only one cat
C. coli
isolate was resistant to both azithromycin and erythromycin. One
C. jejuni
isolate from a fountain was resistant to four antimicrobial agents (erythromycin, azithromycin, tetracycline and ciprofloxacin).
Conclusions
The study proved that surface water, poultry meat and pets constituted potential sources of
Campylobacter
to children. Fountains can be a direct source of children campylobacteriosis but can also pollute other environments with multidrug-resistant
Campylobacter
. The high resistance to some antimicrobials among the isolates may lead to increasing numbers of difficult-to-treat campylobacteriosis cases among children.
Journal Article
Genomic diversity of Campylobacter jejuni and Campylobacter coli isolated from the Ethiopian dairy supply chain
2024
Campylobacteriosis outbreaks have previously been linked to dairy foods. While the genetic diversity of Campylobacter is well understood in high-income countries, it is largely unknown in low-income countries, such as Ethiopia. This study therefore aimed to conduct the first genomic characterization of Campylobacter isolates from the Ethiopian dairy supply chain to aid in future epidemiological studies. Fourteen C . jejuni and four C . coli isolates were whole genome sequenced using an Illumina platform. Sequences were analyzed using the bioinformatics tools in the GalaxyTrakr platform to identify MLST types, and single nucleotide polymorphisms, and infer phylogenetic relationships among the studied isolates. Assembled genomes were further screened to detect antimicrobial resistance and virulence gene sequences. Among 14 C . jejuni , ST 2084 and ST 51, which belong to the clonal complexes ST-353 and ST-443, respectively, were identified. Among the 4 sequenced C . coli isolates, two isolates belonged to ST 1628 and two to ST 830 from the clonal complex ST-828. The isolates of C . jejuni ST 2084 and ST 51 carried β-lactam resistance gene blaOXA-605 , a fluoroquinolone resistance-associated mutation T86I in the gryA gene, and a macrolide resistance-associated mutation A103V in 50S L22 . Only ST 2084 isolates carried the tetracycline resistance gene tetO . Conversely, all four C . coli ST 830 and ST 1628 isolates carried tetO , but only ST 1628 isolates also carried blaOXA-605 . Lastly, C . jejuni ST 2084 isolates carried a total of 89 virulence genes, and ST 51 isolates carried up to 88 virulence genes. Among C . coli , ST 830 isolates carried 71 genes involved in virulence, whereas two ST 1628 isolates carried up to 82 genes involved in virulence. Isolates from all identified STs have previously been isolated from human clinical cases, demonstrating a potential food safety concern. This finding warrants further monitoring of Campylobacter in dairy foods in Ethiopia to better understand and manage the risks associated with Campylobacter contamination and transmission.
Journal Article
Comparative genomics and virulence potential of Campylobacter coli strains isolated from different sources over 25 years in Brazil
by
Soares, Siomar de Castro
,
Ceballos, Victor Augusto Sallum
,
Gomes, Carolina Nogueira
in
Animals
,
Antimicrobial resistance
,
Biological Microscopy
2024
Background
Campylobacter
spp. have been reported as a common cause of gastroenteritis in humans in many countries. However, in Brazil there is insufficient data to estimate the impact of
Campylobacter
in public health. In light of the importance of this foodborne pathogen, the aim of this study was to perform comparative analyses on 80 Brazilian
Campylobacter coli
genomes isolated from human feces, animals, the environment, and food. Methods include Average Nucleotide Identity (ANI), Gegenees, genomic plasticity, presence of pathogenicity, resistance, and metabolic islands. In addition, virulence analysis in
Galleria mellonella
were also performed for 18 selected
C. coli
strains.
Results
The ANI values confirmed that all strains belonged to the
C. coli
species. Phylogenetic analyses demonstrated the evolutionary relationships among the studied strains, highlighting the genetic diversity among them. The differences in shared and deleted regions of the studied genomes were demonstrated, with 16 genomic islands identified, including 4 metabolic islands, 4 resistance islands, and 8 pathogenicity islands. We detected genes associated with chemotaxis, exotoxin production, antimicrobial resistance, stress response, defense mechanisms, and intracellular survival among these islands, highlighting the pathogenic potential of these strains. Two strains isolated from human and one from animal showed high virulence, killing 100% of
Galleria mellonella
larvae. Two strains isolated from the environment and two isolated from food killed 70–90% of the larvae and were classified as virulent. Three strains isolated from animal, two from human, two from the environment and one from food killed 30% to 60% of the larvae and were considered of intermediate virulence.
Campylobacter jejuni
ATCC 33291, one strain isolated from human and one from food killed 10 to 20% of the larvae and were considered of low virulence. One strain isolated from food did not kill any larvae and was considered avirulent.
Conclusions
The results obtained highlighted the genetic diversity, pathogenic and virulence potential of many of the
C. coli
strains studied, contributing for a more complete characterization of this important pathogen recognized as a cause of human gastroenteritis.
Journal Article
The role of virulence genes in Campylobacter pathogenicity: a perspective from the Gulf Cooperation Council countries
by
Khalifa, Hazim O.
,
Mohamed, Mohamed-Yousif Ibrahim
,
Habib, Ihab
in
Animals
,
Bacteria
,
Campylobacter
2025
Campylobacter spp., primarily C. jejuni and C. coli , are leading causes of bacterial gastroenteritis worldwide. This review provides an overview of literature on the prevalence and distribution of virulence genes in C. jejuni and C. coli isolated from both food samples and humans across GCC countries. The reviewed evidence highlights a gap in our understanding of how differences in the virulence profile affect the pathogenicity of Campylobacter . Research has shown that C. coli is the predominant species found in retail chicken carcasses in the UAE, while C. jejuni is more common in chicken carcasses across other GCC countries. Studies also reveal distinct genotypes of C. jejuni and C. coli , each with varying pathogenicity. These findings underscore the need for further research on the role of virulence genes in shaping the pathogenicity of Campylobacter, which is essential for developing effective intervention and control strategies in the GCC region.
Journal Article
Whole genome sequencing reveals extended natural transformation in Campylobacter impacting diagnostics and the pathogens adaptive potential
2020
Campylobacter
is the major bacterial agent of human gastroenteritis worldwide and represents a crucial global public health burden. Species differentiation of
C. jejuni
and
C. coli
and phylogenetic analysis is challenged by inter-species horizontal gene transfer. Routine real-time PCR on more than 4000
C. jejuni
and
C. coli
field strains identified isolates with ambiguous PCR results for species differentiation, in particular, from the isolation source eggs. K-mer analysis of whole genome sequencing data indicated the presence of
C. coli
hybrid strains with huge amounts of
C. jejuni
introgression. Recombination events were distributed over the whole chromosome. MLST typing was impaired, since
C. jejuni
sequences were also found in six of the seven housekeeping genes. cgMLST suggested that the strains were phylogenetically unrelated. Intriguingly, the strains shared a stress response set of
C. jejuni
variant genes, with proposed roles in oxidative, osmotic and general stress defence, chromosome maintenance and repair, membrane transport, cell wall and capsular biosynthesis and chemotaxis. The results have practical impact on routine typing and on the understanding of the functional adaption to harsh environments, enabling successful spreading and persistence of
Campylobacter
.
Journal Article
Staphylococcus aureus enhances biofilm formation, aerotolerance, and survival of Campylobacter strains isolated from retail meats
by
Karki, Anand B.
,
Ballard, Kaylee
,
Sheaff, Robert J.
in
631/326
,
631/326/1320
,
Aerobic conditions
2021
In retail meat products,
Campylobacter jejuni
,
C. coli
, and
Staphylococcus aureus
have been reported in high prevalence. The polymicrobial interaction between
Campylobacter
and other bacteria could enhance
Campylobacter
survival during the adverse conditions encountered during retail meat processing and storage. This study was designed to investigate the potential role of
S. aureus
from retail meats in enhancing the survival of
Campylobacter
exposed to low temperature, aerobic conditions, and biofilm formation. Results indicated that viable
S. aureus
cells and filter-sterilized cell-free media obtained from
S. aureus
prolonged the survival of
Campylobacter
at low temperature and during aerobic conditions. Biofilm formation of
Campylobacter
strains was significantly enhanced in the presence of viable
S. aureus
cells, but the results were inconclusive when extracts from cell-free media were used. In conclusion, the presence of
S. aureus
cells enhances survivability of
Campylobacter
strains in adverse conditions such as low temperature and aerobic conditions. Further investigations are warranted to understand the interaction between
Campylobacter
and
S. aureus
, and effective intervention strategies are needed to reduce the incidence of both foodborne pathogens in retail meat products.
Journal Article
Molecular Detection of Virulence‐Associated Markers in Campylobacter coli and Campylobacter jejuni Isolates From Water, Cattle, and Chicken Faecal Samples From Kajiado County, Kenya
by
Bebora, Lilly C.
,
Aboge, Gabriel O.
,
Wanja, Daniel W.
in
Animals
,
Annealing
,
Bacterial Proteins - genetics
2024
Campylobacter is a zoonotic foodborne pathogen that is often linked with gastroenteritis and other extraintestinal infections in humans. This study is aimed at determining the genetic determinants of virulence‐encoding genes responsible for flagellin motility protein A ( flaA ), Campylobacter adhesion to fibronectin F ( cadF ), Campylobacter invasion antigen B ( ciaB ) and cytolethal distending toxin (cdt) A ( cdtA ) in Campylobacter species. A total of 29 Campylobacter coli isolates (16 from cattle, 9 from chicken, and 4 from water samples) and 74 Campylobacter jejuni isolates (38 from cattle, 30 from chicken, and 6 from water samples) described in an earlier study in Kajiado County, Kenya, were examined for the occurrence of virulence‐associated genes using polymerase chain reaction (PCR) and amplicon sequencing. The correlations among virulence genes were analyzed using Pearson’s correlation coefficient ( R ) method. Among the 103 Campylobacter strains screened, 89 were found to harbour a single or multiple virulence gene(s), giving an overall prevalence of 86.4%. C. jejuni strains had the highest prevalence of multivirulence at 64.9% (48/74), compared to C . coli (58.6%, 17/29). The ciaB and flaA genes were the most common virulence genes detected in C . jejuni (81.1% [60/74] and 62.2% [46/74], respectively) and in C. coli (each at 62.1%; 18/29). Campylobacter isolates from chicken harboured the most virulence‐encoding genes. C. jejuni strains from chicken and cattle harboured the highest proportions of the cdtA and ciaB genes, respectively. All the C. coli strains from water samples harboured the cadF and flaA genes. The results obtained further revealed a significant positive correlation between cadF and flaA ( R = 0.733). C. jejuni and C. coli strains from cattle, chicken, and water harbour virulence markers responsible for motility/colonization, invasion, adherence, and toxin production, evoking their important role in campylobacteriosis development among humans and livestock. The identification of cattle, chicken, and water samples as reservoirs of virulent Campylobacter spp. highlights the possible risk to human health. These data on some virulence genes of Campylobacter will assist food safety and public health officials in formulating policy statements.
Journal Article
Characterization of Antimicrobial Susceptibility and Its Association with Virulence Genes Related to Adherence, Invasion, and Cytotoxicity in Campylobacter jejuni and Campylobacter coli Isolates from Animals, Meat, and Humans
by
San Martín, Betty
,
Vidal, Maricel
,
Martínez, María Cristina
in
Adhesins, Bacterial - genetics
,
Adhesins, Bacterial - metabolism
,
Animals
2016
The aim of this research was to statistically analyze the association between antimicrobial susceptibility/resistance to erythromycine, gentamicin, ciprofloxacin, and tetracycline and 11 virulence genes associated with adherence, invasion, and cytotoxicity in 528 isolates of
Campylobacter coli
and
Campylobacter jejuni
obtained from retail meat and fecal samples from food-producing animals and human patients. A high percentage of
Campylobacter
strains were resistant to antimicrobials, specifically ciprofloxacin and tetracycline. Moreover, we observed a wide distribution of virulence genes within the analyzed strains.
C. jejuni
strains were more susceptible to antimicrobials, and showed greater number of virulence genes than
C. coli
strains. Genes related to invasion capability, such as
racR, ciaB,
and
pldA,
were associated with antimicrobial-susceptible strains in both species. The genes
cdtA
and
dnaJ,
a citotoxin unit and an adherence-related gene, respectively, were associated with antimicrobial-resistant strains in both species. In conclusion,
Campylobacter
strains show a statistically significant association between antimicrobial susceptibility and the presence of virulence genes.
Journal Article
Clinical impact of the type VI secretion system on virulence of Campylobacter species during infection
2019
Background
The clinical course of
Campylobacter
infection varies in symptoms and severity depending on host factors, virulence of the pathogen and initiated therapy. The type VI secretion system (T6SS) has been identified as a novel virulence factor, which mediates contact-dependent injection of enzymes and toxins into competing bacteria or host cells and facilitates the colonisation of a host organism. We aimed to compare the clinical course of
Campylobacter
infection caused by strains with and without the T6SS and identify possible associations between this putative virulence factor and the clinical manifestations of disease.
Methods
From April 2015 to January 2017, patients with detection of
Campylobacter
spp. were identified at the University Hospital of Basel and the University Children’s Hospital of Basel and included in this case-control study. Presence of the T6SS gene cluster was assayed by PCR targeting the
hcp
gene, confirmed with whole genome sequencing. Pertinent clinical data was collected by medical record review. Differences in disease- and host-characteristics between T6SS-positive (case) and –negative (control) were compared in a uni- and multi-variable analysis. Hospital admission, antibiotic therapy, admission to intensive care unit, development of bacteraemia and in-hospital mortality were considered as clinical endpoints.
Results
We identified 138 cases of
Campylobacter jejuni
infections and 18 cases of
Campylobacter coli
infections from a paediatric and adult population. Analyses were focused on adult patients with
C. jejuni
(
n
= 119) of which 16.8% were T6SS-positive. Comparisons between T6SS-positive and -negative
C. jejuni
isolates did not reveal significant differences regarding clinical manifestations or course of disease. All clinical endpoints showed a similar distribution in both groups. A higher score in the Charlson Comorbidity Index was associated with T6SS-positive
C. jejuni
isolates (
p
< 0.001) and patients were more likely to have a solid organ transplant and to be under immunosuppressive therapy.
Conclusions
Our study does not provide evidence that T6SS is associated with a more severe clinical course. Interestingly, T6SS-positive isolates are more commonly found in immunocompromised patients: an observation which merits further investigation.
Journal Article
Genetic characterisation of virulence genes associated with adherence, invasion and cytotoxicity in Campylobacter spp. isolated from commercial chickens and human clinical cases
by
Reddy, Samantha
,
Zishiri, Oliver T.
in
Adherence
,
Agriculture, Dairy & Animal Science
,
Anatomy & Morphology
2018
Virulence-associated genes have been recognised and detected in Campylobacter species. The majority of them have been proven to be associated with pathogenicity. This study aimed to detect the presence of virulence genes associated with pathogenicity and responsible for invasion, expression of adherence, colonisation and production of the cytolethal distending toxin (cdt) in Campylobacter jejuni and Campylobacter coli. Commercial chicken faecal samples were randomly sampled from chicken farms within the Durban metropolitan area in South Africa. Furthermore, human clinical Campylobacter spp. isolates were randomly sampled from a private pathology laboratory in South Africa. Out of a total of 100 chicken faecal samples, 78% (n = 78) were positive for Campylobacter growth on modified charcoal cefoperazone deoxycholate and from the random laboratory collection of 100 human clinical isolates, 83% (n = 83) demonstrated positive Campylobacter spp. growth following culturing methods. These samples were screened for the presence of the following virulence genes: cadF, hipO, asp, ciaB, dnaJ, pldA, cdtA, cdtB and cdtC. As expected, the cadF gene was present in 100% of poultry (n = 78) and human clinical isolates (n = 83). Campylobacter jejuni was the main species detected in both poultry and human clinical isolates, whilst C. coli were detected at a significantly lower percentage (p < 0.05). Eight per cent of the C. jejuni from human clinical isolates had all virulence genes that were investigated. Only one C. coli isolate demonstrated the presence of all the virulence genes investigated; however, the pldA virulence gene was detected in 100% of the C. coli isolates in poultry and a high percentage (71%) in human clinical C. coli isolates as well. The detection of cdt genes was found at higher frequency in poultry than human clinical isolates. The high prevalence rates of virulence genes detected in poultry and human clinical isolates demonstrate their significance in the pathogenicity of Campylobacter species.
Journal Article