Multiple strains of Campylobacter coli, C. jejuni, C. helveticus, C. lari, C. sputorum, and C. upsaliensis isolated from animal, clinical, or food samples have been analyzed by matrix-assisted laser ...desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Whole bacterial cells were harvested from colonies or confluent growth on agar and transferred directly into solvent and then to a spot of dried 3-methoxy-4-hydroxycinnamic acid (matrix). Multiple ions in the 5,000- to 15,000-Da mass range were evident in spectra for each strain; one or two ions in the 9,500- to 11,000-Da range were consistently high intensity. "Species-identifying" biomarker ions (SIBIs) were evident from analyses of multiple reference strains for each of the six species, including the genome strains C. jejuni NCTC 11168 and C. jejuni RM1221. Strains grown on nine different combinations of media and atmospheres yielded SIBI masses within ±5 Da with external instrument calibration. The highest-intensity C. jejuni SIBIs were cytosolic proteins, including GroES, HU/HCj, and RplL. Multiple intraspecies SIBIs, corresponding probably to nonsynonymous nucleotide polymorphisms, also provided some intraspecies strain differentiation. MALDI-TOF MS analysis of 75 additional Campylobacter strains isolated from humans, poultry, swine, dogs, and cats revealed (i) associations of SIBI type with source, (ii) strains previously speciated incorrectly, and (iii) "strains" composed of more than one species. MALDI-TOF MS provides an accurate, sensitive, and rapid method for identification of multiple Campylobacter species relevant to public health and food safety.
Background. Campylobacter species cause a high proportion of bacterial gastroenteritis cases and are a significant burden on health care systems and economies worldwide; however, the relative ...contributions of the various possible sources of infection in humans are unclear. Methods. National-scale genotyping of Campylobacter species was used to quantify the relative importance of various possible sources of human infection. Multilocus sequence types were determined for 5674 isolates obtained from cases of human campylobacteriosis in Scotland from July 2005 through September 2006 and from 999 Campylobacter species isolates from 3417 contemporaneous samples from potential human infection sources. These data were supplemented with 2420 sequence types from other studies, representing isolates from a variety of sources. The clinical isolates were attributed to possible sources on the basis of their sequence types with use of 2 population genetic models, STRUCTURE and an asymmetric island model. Results. The STRUCTURE and the asymmetric island models attributed most clinical isolates to chicken meat (58% and 78% of Campylobacter jejuni and 40% and 56% of Campylobacter coli isolates, respectively), identifying it as the principal source of Campylobacter infection in humans. Both models attributed the majority of the remaining isolates to ruminant sources, with relatively few isolates attributed to wild bird, environment, swine, and turkey sources. Conclusions. National-scale genotyping was a practical and efficient methodology for the quantification of the contributions of different sources to human Campylobacter infection. Combined with the knowledge that retail chicken is routinely contaminated with Campylobacter, these results are consistent with the view that the largest reductions in human campylobacteriosis in industrialized countries will come from interventions that focus on the poultry industry.
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.
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.
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.
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.
spp., especially
and
, are leading bacterial foodborne pathogens worldwide. In the United States, an estimated 0.8 million cases of campylobacteriosis occur annually, mostly involving
...Campylobacteriosis is generally self-limiting, but in severe cases, treatment with antibiotics may be mandated. The increasing incidence of fluoroquinolone resistance in
has rendered macrolides such as erythromycin and azithromycin the drugs of choice for human campylobacteriosis. The prevalence of macrolide resistance in
remains low, but macrolide resistance can be common in
Substitutions in the 23S rRNA gene, specifically A2075G, and less frequently A2074C/G, remain the most common mechanism for high-level resistance to macrolides. In
, resistance mediated by such substitutions is accompanied by a reduced ability to colonize chickens and other fitness costs, potentially contributing to the low incidence of macrolide resistance. Interestingly, similar fitness impacts have not been noted in
Also noteworthy is a novel mechanism first reported in 2014 for a
isolate from China and mediated by
(B) harbored on multidrug resistance genomic islands. The incidence of
(B) appears to reflect clonal expansion of certain strains, and whole-genome sequencing has been critical to the elucidation of
(B)-associated macrolide resistance in
spp. With the exception of one report from Spain,
(B)-mediated macrolide resistance has been restricted to
spp., mostly
, of animal and human origin from China. If
(B)-mediated macrolide resistance does not confer fitness costs in
, the range of this gene may expand in
, threatening to compromise treatment effectiveness for severe campylobacteriosis cases.
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.
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).
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.
Aims
Genetic diversity and antimicrobial resistance of Campylobacter coli and Campylobacter jejuni were investigated along the broiler chicken production chain in central Italy.
Methods and Results
...Campylobacter sp. isolated from cloacal swabs in farms (n = 116) and from the neck skin of chilled and eviscerated carcasses at slaughter (n = 24) were identified as C. coli (n = 99) and C. jejuni (n = 41) by multiplex PCR. Characterization by single amplified fragment length polymorphism (s‐AFLP) revealed a specific genotype of Campylobacter for each farm. Minimal inhibitory concentration showed high prevalence of fluoroquinolones (70%), tetracycline (70%) and erythromycin (30%) resistance among C. coli isolates. Campylobacter jejuni isolates showed lower prevalence of fluoroquinolone (39%) and tetracycline (10%) resistance, and all isolates were susceptible to erythromycin. The S‐AFLP types of the C. coli and C. jejuni isolates were associated with their antimicrobial resistance profiles (P < 0·001).
Conclusions
The genetic diversity detected in Campylobacter isolates suggested that a specific genotype was harboured in each farm. A considerable number of C. coli isolates were resistant to erythromycin.
Significance and Impact of the Study
Campylobacter coli was detected more frequently than C. jejuni in contrast to common findings for poultry. The high prevalence of 30% resistance to erythromycin in C. coli strains isolated from poultry is worrisome, as this is the first antibiotic of choice to treat human campylobacteriosis.
Campylobacter spp. is a major cause of foodborne diseases in humans, particularly when transmitted by the handling or consumption of undercooked poultry meat. Most Campylobacter infections are ...self-limiting, but antimicrobial treatment (e.g., fluoroquinolones and macrolides) is necessary in severe or prolonged cases. The indiscriminate use of these drugs, both in clinical medicine and animal production, has a major impact on public health. The aim of the present study was to identify Campylobacter strains, isolated from turkey and broilers, using both PCR and the matrix-assisted laser desorption-ionization time-of-flight (MALDI-TOF) methods to reveal the accuracy of identification, as well to evaluate the antimicrobial and genetic resistance of the investigated strains. MALDI-TOF and PCR methods were used to show differences, if any, in the specificity of that test. In this study, MALDI-TOF mass spectrometry gave the same results as multiplex PCR, in all cases. The highest rate of resistance (i.e., 100% of turkey and broiler strains) was detected against ciprofloxacin, whereas 58.1% of turkey and 78.6% of broiler strains were resistant to tetracycline. Multidrug-resistant isolates were not found in the study. All ciprofloxacin-resistant strains had a mutation in the gyrA gene, at the Thr-86 position. The presence of the tetO gene was found in 71% of turkey and in 100% of broiler strains. All resistant to tetracycline strains included tetO gene. Additionally, in five turkey and three broiler strains, susceptible to tetracycline, tetO gene was present. These results indicate the high prevalence of Campylobacter strains, which are phenotypically and genetically resistant to fluoroquinolones and tetracycline.
The prevalence and antimicrobial resistance of
Campylobacter spp. in broiler chickens were determined in Shandong Province, China. In total, 275
Campylobacter isolates were obtained from 767 broiler ...cecal samples
, including 208
Campylobacter jejuni, 53
Campylobacter coli, and 14 unidentified
Campylobacter isolates. Minimal inhibitory concentrations of 11 antimicrobial agents were determined using the agar dilution method recommended by CLSI. More than 98% of the tested
Campylobacter isolates were resistant to quinolones (nalidixic acid, ciprofloxacin and enrofloxacin) and tetracyclines (tetracycline and doxycycline). The
C. jejuni isolates also exhibited a high rate of resistance to phenicol antibiotics and a moderate rate of resistance to macrolides and gentamicin. On the contrary, the
C. coli isolates showed a high-level resistance to macrolides and gentamicin and little resistance to phenicol antibiotics. The vast majority of the
Campylobacter isolates were classified as multidrug resistant. These findings reveal a broad extent of antimicrobial resistance in
Campylobacter isolates from poultry in China and underline the need for prudent use of antibiotics in poultry production to minimize the spread of antibiotic resistant
Campylobacter.
In recent years, increasing numbers of consumers have become interested in feeding raw food for their pet dogs as opposed to commercial dry food, in the belief of health advantages. However, raw meat ...and internal organs, possibly contaminated by pathogens such as Campylobacter spp., may pose a risk of transmission of zoonoses to the pet owners. Campylobacter jejuni is the leading cause of bacterial gastroenteritis in humans but C. upsaliensis has also been associated with human disease. In this study we investigated the effect of different feeding strategies on the prevalence of Campylobacter spp. in Finnish dogs. We further characterized the isolates using multilocus sequence typing (MLST), whole-genome (wg) MLST and antimicrobial susceptibility testing. Dogs were sampled before and after a feeding period consisting of commercial raw feed or dry pellet feed. Altogether 56% (20/36) of the dogs yielded at least one Campylobacter-positive fecal sample. C. upsaliensis was the major species detected from 39% of the dogs before and 30% after the feeding period. Two C. jejuni isolates were recovered, both from raw-fed dogs after the dietary regimen. The isolates represented the same genotype (ST-1326), suggesting a common infection source. However, no statistically significant correlation was found between the feeding strategies and Campylobacter spp. carriage. The global genealogy of MLST types of dog and human C. upsaliensis isolates revealed weakly clonal population structure as most STs were widely dispersed. Major antimicrobial resistance among C. upsaliensis isolates was against streptomycin (STR MIC > 4 mg/l). Apart from that, all isolates were highly susceptible against the antimicrobials tested. Mutations were found in the genes rpsL or rpsL and rsmG in streptomycin resistant isolates. In conclusion, increasing trend to feed dogs with raw meat warrants more studies to evaluate the risk associated with raw feeding of pets in transmission of zoonoses to humans.
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