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1.
AIM: To identify potential reservoirs and transmission routes of human pathogenic Campylobacter spp. METHODS AND RESULTS: An enrichment PCR method for the detection and identification of Campylobacter jejuni and/or Campylobacter coli in faecal, food and river water samples was applied to 1450 samples of 12 matrix types obtained from a defined geographical area. PCR-positive samples were cultured to yield isolates for typing, and the data for 616 C. jejuni isolates obtained. Serotyping and SmaI macrorestriction profiling using pulsed field gel electrophoresis revealed a high level of diversity within the isolates from each matrix. Campylobacter jejuni and C. coli subtypes indistinguishable from those obtained from human cases were detected in most of the matrices examined. No Campylobacter isolates were isolated from possum faeces. CONCLUSIONS: Ten of the 12 matrices examined may be involved in the transmission of human campylobacteriosis as they contained Campylobacter subtypes also isolated from clinical cases. SIGNIFICANCE AND IMPACT OF THE STUDY: Results indicate that, for this rural population, a range of potential transmission routes that could lead to campylobacteriosis exist. Their relative importance needs to be assessed from an exposure assessment standpoint.  相似文献   

2.
AIM: To analyse Campylobacter jejuni typing data to define statistically which potential reservoirs and transmission sources contain isolates that are most similar to one another and to isolates from human infections. METHODS AND RESULTS: Serotyping and SmaI macrorestriction profiling data for C. jejuni isolates from human campylobacteriosis cases, chicken carcass rinses, duck, sheep, dairy and beef cattle faeces, river water, and sheep, beef and pork offal obtained from a defined rural area of New Zealand were compared using the Czekanowski proportional similarity index. Subtypes of isolates from ruminant animals, whether derived from their faeces or offals, were generally similar to one another. The spectrum of isolate subtypes from human cases was more similar to that from ruminant faeces than the other matrices considered. Isolate subtypes from chicken rinses, pork offal, water and duck faeces were not highly similar to those from other matrices. CONCLUSIONS: Results from a combination of phenotypic and genotypic approaches suggest that, for this rural population, exposures associated with a rural lifestyle may be significant sources of human campylobacteriosis. SIGNIFICANCE AND IMPACT OF THE STUDY: The Czekanowski index was applied to subtyping data and supported the greater importance of contact with livestock in campylobacteriosis cases associated with a rural setting, in comparison with urban studies that have identified poultry-related factors.  相似文献   

3.
To determine the significance of poultry and bovine as infectious sources of Campylobacter jejuni in Japan, the serotype distribution and pulsed-field gel electrophoresis (PFGE) patterns of poultry and bovine isolates were compared with those of isolates from patients with diarrhea in Akita (Japan). Serotypes O:2 and O:4-complex were common in human, poultry, and bovine isolates, and serotype O:23,36,53 was common in human and bovine isolates. SmaI PFGE patterns of isolates belonging to these serotypes were generated. Eight PFGE patterns were shared by poultry and human isolates and three patterns were shared by human and bovine isolates. Further analysis of the isolates having the same SmaI PFGE pattern by KpnI PFGE confirmed that four patterns and two patterns were still shared by poultry and human isolates, and bovine and human isolates, respectively. Thus, serotypic and genotypic data indicated a possible link between sporadic human campylobacteriosis and C. jejuni from retail poultry and bovine bile and feces, suggesting that bovine serves as an infectious source of C. jejuni in Japan, as is observed in other countries.  相似文献   

4.
AIMS: To identify campylobacters isolated from clinically healthy cattle at species level by a multiplex polymerase chain reaction (m-PCR). The heterogeneity among Campylobacter jejuni and Campylobacter coli isolates was also investigated by using a restriction fragment length polymorphism (RFLP) analysis of flagellin (flaA) gene. METHODS AND RESULTS: Samples of intestinal contents, gall bladders, liver and faeces were collected from a total number of 1154 healthy cattle. The samples were inoculated onto Preston enrichment broth and agar. Of 1154 samples, 301 (26.1%) were positive for Campylobacter spp. Using an m-PCR assay for species identification, 179 (59.5%) were positive with C. jejuni specific primers while 30 (10%) were positive with C. coli specific primers. None of the liver samples examined was positive for C. jejuni or C. coli by mPCR. All the isolates identified as C. jejuni and C. coli were successfully subtyped by flaA typing. Of the 209 isolates tested, 28 different flaA types were found. Twenty-three flaA types were identified among 179 C. jejuni isolates and the remaining five from C. coli isolates. CONCLUSIONS: Although the overall results suggest that the degree of heterogeneity among the flaA genes of thermophilic Campylobacter strains isolated from healthy cattle is relatively high, they should be treated cautiously as the number of band types for C. coli was low and band type 8 in C. jejuni was represented by a high percentage (%58). SIGNIFICANCE AND IMPACT OF THE STUDY: The findings of the present study suggest that healthy cattle can play role in the contamination of environment and human food chain by Campylobacter spp.  相似文献   

5.
AIMS: To determine the frequency of coinfection with multiple strains in sporadic cases of human Campylobacter infection. Method and RESULTS: During 1999 10 single colonies of Campylobacter were cultured from each of 53 positive faecal samples. Five isolates were taken from nonselective agar after passive filtration of faecal suspensions and five isolates were taken from selective agar plates. All isolates were sero- and phage typed and their antibiotic resistance determined. Pulsed-field gel electrophoresis and flagellin gene typing were performed on selected isolates. One patient was infected with Camp. coli, the remainder with strains of Camp. jejuni. The majority of patients was infected with a single strain of Campylobacter, but from each of four samples, 7.5%, two strains of Camp. jejuni, confirmed by molecular typing, were identified. CONCLUSION: Coinfection occurs in sporadic cases of campylobacteriosis. SIGNIFICANCE AND IMPACT OF THE STUDY: This study has implications in outbreak investigation when distinct strains have been isolated from epidemiologically related patients and/or the suspected source or vehicle.  相似文献   

6.
AIM: The research focused on the determination of the toxicity variation associated with Campylobacter jejuni isolated from humans and chickens. METHODS AND RESULTS: Campylobacter jejuni isolates were obtained from chicken carcasses and from humans exhibiting symptoms of campylobacteriosis. Using HeLa cells as the in vitro model, toxicity was determined for each isolate. The mean toxicity level of the chicken isolates was significantly lower than that of the human isolates (P < 0.001). There was a wide range of toxicity in C. jejuni isolated from chickens and the percentage of isolates exhibiting low toxicity remaining relatively constant. All C. jejuni isolates from humans possessed either medium or high levels of toxicity. CONCLUSIONS: All wildtype C. jejuni isolates obtained from poultry carcasses may not be equally important as a human foodborne pathogen. SIGNIFICANCE AND IMPACT OF STUDY: Campylobacter jejuni remains a primary foodborne pathogen and increased efforts are needed to determine the impact of wildtype isolates in causing human illness. The present research indicates that all isolates may not be equally important in regards to disease potential. The information found should be included in efforts to develop C. jejuni detection, control and infection modelling.  相似文献   

7.
AIMS: The purpose of this study was to determine the susceptibility of Campylobacter jejuni and Campylobacter coli isolates to antimicrobial agents and to investigate the presence of plasmid DNA. METHODS AND RESULTS: A total of 15 clinical isolates from children faeces, and 29 animal isolates of Campylobacter jejuni (n=22) and Campylobacter coli (n=22) were tested for susceptibility to 9 antimicrobial agents using a disc diffusion method, and screened for the presence of plasmid DNA by agarose gel electrophoresis. Of the 44 isolates, 56.8% were resistant to sulphonamide, 25% to norfloxacin, 18.2% to erythromicin, ciprofloxacin and ampicillin, and 13.6% to tetracycline. All isolates were susceptible to gentamicin, chloramphenicol and cefotaxime. Plasmids were detected in one Camp. jejuni (4.54%) strain isolated from sheep and in six (27.27%) Camp. coli strains isolated from rhesus monkey(3), swine(2), and poultry(1) with sizes ranging from 3.4 to 50 kb. CONCLUSIONS: The majority of the human isolates were susceptible to antibiotics commonly used for the treatment of campylobacteriosis. SIGNIFICANCE AND IMPACT OF THE STUDY: The origin and spread of Campylobacter resistance to antibiotics are discussed, with particular respect to the current situation in Brazil.  相似文献   

8.
We compared Campylobacter jejuni strains isolated from the patient stools associated with two food-borne diarrheal outbreak cases by the serotypic methods (Lior and Penner systems) and the genotypic methods (restriction fragment length polymorphism (RFLP) of flaA gene and pulsed-field gel electrophoresis (PFGE)). Fla-RFLP was based on the digestion of 410 bp DNA fragment by MboI restriction enzyme amplified from a 5' portion of C. jejuni flaA gene. Six distinctive fla-RFLP patterns were identified by examining 29 serotype reference strains and 58 strains isolated from the patients infected with C. jejuni independently. In the first outbreak case, 4 isolates were shown to be the same patterns each other by the fla-RFLP and PFGE, and by the Lior serotyping, except the Penner system that serotyped into 2 distinct types. On the other hand, in the second case, out of 10 isolates, 5 isolates were identical by the both genotypic and the both serotypic methods, and 4 isolates were not differentiated by the fla-RFLP and Penner system, but were separated into 4 types by PFGE in a little difference. The rest isolate was completely different from the other isolates by the all of methods used now. The findings suggest that the second case occurred by the infection of at least 3 different strains of C. jejuni.  相似文献   

9.
AIMS: To study the prevalence of Campylobacter spp. in the faecal material of reindeer, and to identify the isolates by means of a polyphasic approach. In addition, to study the genetic diversity of Camp. hyointestinalis subsp. hyointestinalis reindeer isolates by pulsed-field gel electrophoresis (PFGE). METHODS AND RESULTS: The material, collected during the slaughter period in autumn 1998, comprised 399 faecal contents from the reindeer (Rangifer tarandus), a semi-domesticated, meat-producing ruminant of northern Finland. These samples came from 16 herds in the areas of eight reindeer slaughterhouses. Samples were cultured by methods suitable for isolation of fastidious Campylobacter species. Of all samples, 6% (24/399) were Campylobacter-positive. Phenotypic characteristics, SDS-PAGE protein patterns, dot blot DNA-DNA hybridization, 23S rDNA restriction fragment polymorphism analysis and PFGE identified the isolates as Camp. hyointestinalis subsp. hyointestinalis. CONCLUSIONS: Campylobacter hyointestinalis subsp. hyointestinalis was the only Campylobacter species isolated from reindeer in this study. The isolates showed high genomic diversity in PFGE with the restriction enzymes SmaI and KpnI. SIGNIFICANCE AND IMPACT OF THE STUDY: PFGE analysis is a useful subtyping method for epidemiological studies. Contaminated reindeer meat can be a source for human infections.  相似文献   

10.
AIMS: The aim of the study was to measure the survival of 19 Campylobacter jejuni strains of different origins, including two reference strains, four poultry-derived isolates, nine human isolates and four water isolates, in sterilized drinking water. METHODS AND RESULTS: Pure cultures of 19 C. jejuni strains were inoculated in sterile drinking water and incubated at 4 degrees C for 64 days. Survival was determined by culturability on both selective (Karmali agar) and non-selective [Columbia blood agar (CBA)] media. Culturability was shown to be strain and origin-dependent. Campylobacter jejuni showed prolonged survival on a non-selective than on a selective medium. CONCLUSIONS: The origin of the strain is a determining factor for the survival of C. jejuni in drinking water at 4 degrees C. Poultry isolates showed a prolonged survival, which could be an indication that these strains could play an important role in the transmission of campylobacteriosis through water. In addition, culture conditions are an important factor for evaluating the survival of C. jejuni in drinking water at 4 degrees C. The non-selective agar (CBA) allowed growth of C. jejuni over a longer period of time than the selective agar (Karmali). Furthermore, an enrichment broth (Bolton) allowed the recovery of all 19 C. jejuni strains during the 64 days of incubation at 4 degrees C. SIGNIFICANCE AND IMPACT OF THE STUDY: This study highlighted differences in culturability depending on culture conditions and on strain origin.  相似文献   

11.
AIMS: The main objectives of this study were to investigate the diversity of Campylobacter genotypes circulating in Senegal and to determine the frequency of antibiotic resistance. METHODS AND RESULTS: Strains of Campylobacter jejuni isolated from poultry (n = 99) and from patients (n = 10) and Campylobacter coli isolated from poultry (n = 72) were subtyped by pulsed-field gel electrophoresis (PFGE). The pulsotypes obtained after digestion by SmaI and KpnI revealed a significant genetic diversity in both species, but without any predominant pulsotypes. However, farm-specific clones were identified in the majority of poultry houses (76.5%). Human and poultry isolates of C. jejuni had common PFGE patterns. High quinolone-resistance rates were observed for C. jejuni (43.4%) and C. coli (48.6%) isolates obtained from poultry. CONCLUSIONS: The results showed a genetic diversity of Campylobacter between farms indicating multiple sources of infection; but specific clones had the ability to colonize the broiler farms. The antimicrobial resistance patterns were not related to any specific PFGE pattern suggesting that resistance was due to the selective pressure of antibiotic usage. Campylobacter with similar genotypes were circulating in both human and poultry. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is important for the understanding of the epidemiology of Campylobacter in broiler farms in Senegal. It also emphasizes the need for a more stringent policy in the use of antimicrobial agents in food animals.  相似文献   

12.
AIMS: The aim of this investigation was to compare the usefulness of two previously published flagellin PCR-RFLP typing (Fla-typing) techniques for the subtyping of Campylobacter jejuni strains, in terms of ease of use and discriminatory power. METHODS AND RESULTS: Six groups of isolates, which were epidemiologically unrelated but with similar Fla-types, and five groups of epidemiologically related poultry isolates, with similar PFGE profiles, were used in the comparison. The Fla-typing methods used varied in the number and length of fla-genes amplified and the restriction enzymes used. In addition, the use of separately amplified PCR fragments of both the flaA and flaB genes to generate RFLP profiles was investigated. CONCLUSION: The results clearly demonstrated that both previously published methods exhibit some advantages over the other. However, optimal discrimination was obtained by the use of separately amplified PCR fragments of both fla-genes. SIGNIFICANCE AND IMPACT OF THE STUDY: The subtyping of Camp. jejuni isolates is considered essential for epidemiological purposes. Genotyping methods are now more frequently used but have yet to be standardized. Fla-typing is a rapid and easy to use method with acceptable discriminatory power. However, the discriminatory power of the currently published Fla-typing techniques may be further improved by incorporating RFLP profiles of both fla-genes.  相似文献   

13.
Campylobacter jejuni and C. coli isolates from poultry, cattle, and humans were studied using pulsed-field gel electrophoresis (PFGE) and PCR of candidate livestock-associated marker genes. Human isolates showed 5.7 and 61% overlap with cattle and poultry isolates, respectively, by use of PFGE. No unambiguous association was found between marker genes (the Cj1321 and Cj1324 genes) and livestock-associated isolates.  相似文献   

14.
Abstract PCR-mediated fingerprinting with combined repetitive and arbitrary DNA primers (ERIC-2 and 1026) was used to type Campylobacter jejuni from a milk-associated outbreak, and from sporadic cases of the same and allied HS serotypes. The 14 outbreak strains had identical or similar DNA band profiles whereas the 25 strains from sporadic infections were more heterogeneous with 18 different DNA profiles. Although PCR-based DNA fingerprints lacked serotype specificity, the method was fast, simple to perform and reproducible, provided defined technical protocols were adhered to precisely. Profiles were highly discriminatory but did not consistently match types based on other molecular methods. We conclude that AP-PCR has demonstrable potential for initial rapid investigation of outbreaks, and when used in conjunction with PFGE analysis of DNA restriction profiles, provides a high resolution strategy for accurately defining subtypes of C. jejuni .  相似文献   

15.
Campylobacter infections are the most common cause of bacterial enteritis in humans, and nearly 8% of such infections are caused by Campylobacter coli. Most studies have concentrated on Campylobacter jejuni, frequently isolated from intensively farmed poultry and livestock production units, and few studies have examined the spread and relatedness of Campylobacter across a range of geographical and host boundaries. Systematic sampling of a 100-km2 area of mixed farmland in northwest England yielded 88 isolates of C. coli from a range of sample types and locations, and water was heavily represented. Screening for antibiotic resistance revealed a very low prevalence of resistance, while genotyping performed by using three methods (flaA PCR restriction fragment length polymorphism [RFLP], pulsed-field gel electrophoresis [PFGE], and fluorescent amplified fragment length polymorphism [fAFLP]) provided insights into the genomic relatedness of isolates from different locations and hosts. Isolates were classified into 23 flaA groups, 34 PFGE groups, and five major fAFLP clusters. PFGE banding analysis revealed a high level of variability and no clustering by sample type. fAFLP and flaA analyses successfully grouped the isolates by sample type. We report preliminary findings suggesting that there is a strain of C. coli which may have become adapted to survival or persistence in water and that there is a group of mainly water-derived isolates from which unusual flaA PCR fragments were recovered.  相似文献   

16.
AIMS: To use a published polymerase chain reaction (PCR) method for the detection and identification of thermotolerant Campylobacter species (Camp. jejuni, Camp. coli and Camp. lari) in tandem with a Most Probable Number (MPN) technique to enumerate these species in water samples. METHODS AND RESULTS: An initial study of 42 river water samples compared the use of conventional culture and PCR methods for the detection of Campylobacter in MPN enrichment tubes. It was found that all samples positive by culture were also positive by PCR. Thirty-seven percent more MPN tubes were positive by PCR compared with culture. The MPN/PCR technique was subsequently applied to 96 additional samples collected from rivers, drinking, roof and shallow ground water. Campylobacter was especially prevalent in river water (60% positive) and shallow ground water (75% positive) samples. Drinking water (29.2% positive) and roof water (37.5% positive) also contained Campylobacter, but the numbers detected were very low (maximum 0.3 and 0.56 MPN 100 ml-1, respectively). CONCLUSION: River waters contained Campylobacter at higher levels than any other water type and in a high percentage of the samples. Although Campylobacter was present in treated drinking water, the levels detected were low. SIGNIFICANCE AND IMPACT OF THE STUDY: These results suggest that water may act as a significant transmission route for human campylobacteriosis.  相似文献   

17.
AIMS: To apply and evaluate LG (LPS genes) genotyping, which is a genotyping method based on a cluster of genes involved in the synthesis of surface lipopolysaccharides (LPS) in Campylobacter species, for typing of Campylobacter jejuni isolates obtained from Danish broiler chickens. Furthermore, the LG genotyping method was used to study the genetic stability of four C. jejuni strains after gastrointestinal passage through experimentally infected chickens. METHODS AND RESULTS: In the present study, the LG genotyping method was modified with respect to the restriction enzymes used. To validate the method, 63 Penner serotype reference strains and 107 C. jejuni chicken isolates, representing the most common Penner serotypes of C. jejuni in Danish poultry, were selected for typing. The method was successfully used for typing all isolates and the LG genotype profiles were reproducible. There were no changes in the LG genotype of the C. jejuni strains obtained after experimental passage through chickens. CONCLUSIONS: All C. jejuni strains obtained from broiler chickens were typeable by the LG genotyping method. Application of the RsaI restriction enzyme improved the method in terms of ease and consistency of analyses and increase of discriminatory power. SIGNIFICANCE AND IMPACT OF THE STUDY: The LG genotyping method is a valuable tool for typing C. jejuni isolates obtained from poultry. However, the association between Penner serotyping based on passive haemagglutination of heat-stable antigens and LG genotyping was low when applied to poultry isolates. This is in contrast to previous studies on isolates of human origin that reported a high correlation between results obtained by the two typing methods (Shi et al. 2002).  相似文献   

18.
In developing countries, as well as in many western countries, members of the genus Campylobacter are recognized as one of the most common cause of acute bacterial enteritis. Campylobacter jejuni and Campylobacter coli isolation rates have been shown to be equal to, and sometimes higher than those of other enteric pathogens. The Microbiology Laboratory of the local Public Health Authority in Prahova County conducted a one and a half-year laboratory-based survey of Campylobacter infections in patients suffering from gastrointestinal symptoms. From a total of 3284 stool samples screened, the culture-positive ones confirmed the bacterial etiology for 551 diarrhea cases. Campylobacter was found in 345 specimens, being the most frequently isolated enteropathogen. C. jejuni outnumbered C. coli species (239 vs. 106 isolates). Salmonella isolates were the second local cause of diarrhea. The highest isolation rate of Campylobacter was found in children 5 years of age (262 strains). The prevalence of campylobacteriosis declined with age. The isolation rate of Campylobacter (10.5%), the unimodal age-specific distribution of cases, as well as the identification of polymicrobial infections among the screened population were epidemiological aspects resembling reports on campylobacteriosis in developing countries. The susceptibility of Campylobacter isolates to various antimicrobial agents, including macrolides and fluoroquinolones was also assessed. Among the screened isolates, Erythromycin retained a good activity, while an increased ciprofloxacin resistance was observed. The information gathered through this local study sustains the importance of Campylobacter in the etiology of autochthonous infectious diarrhea. A development of a national surveillance program regarding the most important foodborne pathogens would be beneficial for improving prevention and controlling measures.  相似文献   

19.
The emergence of antimicrobial resistance in Campylobacter spp. has been a growing public health concern globally. The objectives of this study were to determine the prevalence, antimicrobial susceptibility, and genetic relatedness of Campylobacter spp. recovered by the National Antimicrobial Resistance Monitoring System (NARMS) retail meat program. Retail meat samples (n = 24,566) from 10 U.S. states collected between 2002 and 2007, consisting of 6,138 chicken breast, 6,109 ground turkey, 6,171 ground beef, and 6,148 pork chop samples, were analyzed. A total of 2,258 Campylobacter jejuni, 925 Campylobacter coli, and 7 Campylobacter lari isolates were identified. Chicken breast samples showed the highest contamination rate (49.9%), followed by ground turkey (1.6%), whereas both pork chops and ground beef had <0.5% contamination. The most common resistance was to doxycycline/tetracycline (46.6%), followed by nalidixic acid (18.5%), ciprofloxacin (17.4%), azithromycin and erythromycin (2.8%), telithromycin (2.4%), clindamycin (2.2%), and gentamicin (<0.1%). In a subset of isolates tested, no resistance to meropenem and florfenicol was seen. C. coli isolates showed higher resistance rates to antimicrobials, with the exception of doxycycline/tetracycline, than those seen for C. jejuni. Pulsed-field gel electrophoresis (PFGE) fingerprinting resulted in 1,226 PFGE profiles among the 2,318 isolates, with many clones being widely dispersed throughout the 6-year sampling period.  相似文献   

20.
Seven cases of Campylobacter infection, each of them involving two isolates, were analysed. Study of their biochemical profiles and susceptibility patterns allowed the identification of Camp. jejuni and Camp. coli isolates and the effective typing of Camp. jejuni strains into biotypes. Genotyping was carried out by comparing chromosomal DNA restriction patterns obtained by cleavage with Bgl II and Eco RV and by Southern hybridization experiments. These studies revealed clonal homogeneity between both isolates in five of the seven cases studied, indicating that in these cases Campylobacter infection was caused by a single strain. Infection with two different strains was characterized in only two of the seven cases studied, two different species belonging to Camp. coli and Camp. jejuni ssp. jejuni biotype 1 being identified. Genetic analysis proved to be the most reliable technique to achieve precise identification of strains and to elucidate clonal heterogeneity among Campylobacter isolates obtained from a single patient.  相似文献   

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