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The recent detection and isolation of the aflagellate Campylobacter ureolyticus (previously known as Bacteroides ureolyticus) from intestinal biopsy specimens and fecal samples of children with newly diagnosed Crohn's disease led us to investigate the pathogenic potential of this bacterium. Adherence and gentamicin protection assays were employed to quantify the levels of adherence to and invasion into host cells. C. ureolyticus UNSWCD was able to adhere to the Caco-2 intestinal epithelial cell line with a value of 5.341% ± 0.74% but was not able to invade the Caco-2 cells. The addition of two proinflammatory cytokines, tumor necrosis factor alpha (TNF-α) and gamma interferon (IFN-γ), to the cell line did not affect attachment or invasion, with attachment levels being 4.156% ± 0.61% (P = 0.270) for TNF-α and 6.472% ± 0.61% (P = 0.235) for IFN-γ. Scanning electron microscopy visually confirmed attachment and revealed that C. ureolyticus UNSWCD colonizes and adheres to intestinal cells, inducing cellular damage and microvillus degradation. Purification and identification of the C. ureolyticus UNSWCD secretome detected a total of 111 proteins, from which 29 were bioinformatically predicted to be secretory proteins. Functional classification revealed three putative virulence and colonization factors: the surface antigen CjaA, an outer membrane fibronectin binding protein, and an S-layer RTX toxin. These results suggest that C. ureolyticus has the potential to be a pathogen of the gastrointestinal tract.

Background: Gastrointestinal infections have been proposed to predict subsequent irritable bowel syndrome (IBS) but large-scale infectious events are rare and long-term data are missing., Methods: We identified 576 individuals with a Salmonella or Campylobacter infection between 2000 and 2009 that were followed by a short postal questionnaire asking for the presence of current symptoms in 2010. In case of agreement (n = 90), an extended postinfectious (PI)-IBS questionnaire was mailed including the Hospital Anxiety Depression Scale and the Patient Health Questionnaire., Key Results: A total of 189 patients reported back (36%); 98 had a Salmonella and 91 had a Campylobacter infection, of which 56 reported persistent symptoms (9.7% of the initial sample). Fifty-one patients returned the PI-IBS questionnaire. Of 48 patients with complete data, 15 reported no or mild symptoms of abdominal pain or discomfort while 17 had moderate and 16 severe symptoms. Twenty-two met Rome IBS criteria, 14 (29%) reported GI symptoms before the infection. Patients with moderate and/or severe PI-IBS symptoms were significantly more often females, were more often infected by Salmonella than by Campylobacter, had more severe symptoms during the initial infection, and had more often GI symptoms prior to the infection. They reported higher anxiety, depression, and somatisation scores, but were not different with respect to acute stool habits., Conclusions & Inferences: Nearly 10% of patients with an intestinal bacterial infection report postinfectious symptoms up to 10 years after the infectious event. They represent a clinically important population with high psychiatric comorbidity and somatic symptom burden., (© 2011 Blackwell Publishing Ltd.)

We studied etiologic structure of bacterial intestinal infections in monkeys of Adler nursery. A total of 533 monkeys with diarrhea syndrome and monkeys dead from intestinal infections, as well as clinically healthy monkeys and animals dead from other pathologies were examined by bacteriological and molecular-genetic methods. Pathogenic enterobacteria Shigella and Salmonella and microaerophile Campylobacter were found in 5 and 19%, respectively. A high percentage (49%) of intestinal diseases of unknown etiology was revealed in monkeys. The fact that the number of detected opportunistic enterobacteria did not differ in healthy and diseased monkeys suggests that they are not involved into the etiology of intestinal disease.

Background: There has been a marked global increase in the incidence of human Campylobacter enteritis in recent years. This study investigated the epidemiological and clinical features of Campylobacter enteritis in adult patients suffering from acute diarrhea., Methods: This was a retrospective review of Campylobacter enteritis in adult patients with acute diarrhea presenting at Beijing University First Hospital, Beijing, China, in the summer and autumn (April to October) of 2005 to 2009. The data collected included the species of campylobacter identified, and the age, gender, clinical manifestations and results of laboratory test on stool samples collected from the patients. Campylobacter sensitivity tests to various antimicrobial agents were conducted on 80 specimens. Chi-square tests were applied using SPSS13.0 software and a two-sided P value of < 0.05 was considered statistically significant., Results: Campylobacter spp. isolated from the stool specimens of 142 patients with diarrhea represented 14.9% of all the cases examined. C. jejuni was identified in 127 patients (89.4%) and C. coli in 15 others (10.6%). The infection incidence was highest in the age range of 21 - 30 years which comprised 21.7% of the total cases examined. Most cases of diarrhea (46 patients) occurred in June. Watery diarrhea (97.2%), abdominal pain (72.5%) and fever (64.8%) were the most common manifestations of enteric campylobacteriosis. Only four patients (2.8%) had bloody diarrhea. The antimicrobial resistance rates were: cefoperazone (100%), levofloxacin (61.3%), gentamicin (12.5%), erythromycin (6.3%), and azithromycin (2.5%)., Conclusions: Campylobacter was prevalent among adults with acute diarrhea from 2005 to 2009 in Beijing, China. The large number of those afflicted by the disease warrants the commission of a large multicenter study to determine the extent of enteric campylobacteriosis in this region.

Background: Campylobacter concisus is an emerging enteric pathogen, yet it is commonly isolated from feces and the oral cavities of healthy individuals. This genetically complex species is comprised of several distinct genomospecies which may vary in pathogenic potential., Results: We compared pathogenic and genotypic properties of C. concisus fecal isolates from diarrheic and healthy humans residing in the same geographic region. Analysis of amplified fragment length polymorphism (AFLP) profiles delineated two main clusters. Isolates assigned to AFLP cluster 1 belonged to genomospecies A (based on genomospecies-specific differences in the 23S rRNA gene) and were predominantly isolated from healthy individuals. This cluster also contained a reference oral strain. Isolates assigned to this cluster induced greater expression of epithelial IL-8 mRNA and more frequently contained genes coding for the zonnula occludins toxin and the S-layer RTX. Furthermore, isolates from healthy individuals induced greater apoptotic DNA fragmentation and increased metabolic activity than those from diarrheic individuals, and isolates assigned to genomospecies A (of which the majority were from healthy individuals) exhibited higher haemolytic activity compared to genomospecies B isolates. In contrast, AFLP cluster 2 was predominated by isolates belonging to genomospecies B and those from diarrheic individuals. Isolates from this cluster displayed greater mean epithelial invasion and translocation than cluster 1 isolates., Conclusion: Two main genetically distinct clusters (i.e., genomospecies) were identified among C. concisus fecal isolates from healthy and diarrheic individuals. Strains within these clusters differed with respect to clinical presentation and pathogenic properties, supporting the hypothesis that pathogenic potential varies between genomospecies. ALFP cluster 2 isolates were predominantly from diarrheic patients, and exhibited higher levels of epithelial invasion and translocation, consistent with known roles for these factors in diarrhoeal disease. Conversely, isolates from healthy humans and AFLP cluster 1 or genomospecies A (which were predominantly isolated from healthy humans) exhibited increased haemolytic ability, apoptotic DNA fragmentation, IL-8 induction, and/or carriage of toxin genes. Given that this cluster contains an oral reference strain, it is possible that some of the AFLP cluster 1 isolates are periodontal pathogens and may cause disease, albeit via a different mechanism than those from AFLP cluster 2.

Objectives: The main objectives of this study were to establish baseline characteristics for milkborne outbreaks, establish an expected milkborne outbreak profile, and identify potential indicators of food terrorism., Materials: This study used 1990-2006 data from the Centers for Disease Control and Prevention Annual Listings of Disease Outbreaks and the Foodborne Outbreak Database (FOOD) to establish epidemiologic baseline characteristics for disease outbreaks associated with fluid milk. FOOD data from 2007 were used to qualitatively validate the potential of the baseline characteristics and the expected outbreak profile., Results: Eighty-three fluid milkborne outbreaks were reported between 1990 and 2006, resulting in 3621 illnesses. The mean number of illnesses per outbreak was 43.6 (illness range: 2-1644). Consumption of unpasteurized milk was associated with 55.4% of reported outbreaks. Campylobacter spp., Escherichia coli, and Salmonella spp. caused 51.2%, 10.8%, and 9.6% of reported outbreaks, respectively. Private homes accounted for 41.0% of outbreak locations. Number ill, outbreak location, and etiology were the primary characteristics which could signal a potential intentional contamination event. In 2007, one pasteurized milk outbreak caused by Listeria was flagged as aberrative compared with the expected outbreak profile., Conclusions: The creation and dissemination of expected outbreak profiles and epidemiologic baseline characteristics allow public health and Homeland Security officials to quickly assess the potential of intentional food contamination. A faster public health and medical system response can result in decreased morbidity and mortality.

Background: Diarrhea is the most common illness among travelers and expatriates in Nepal. Published data on the etiology of travelers' diarrhea (TD) in Nepal are over 13 years old and no prior data exist on antibiotic susceptibility for currently used drugs. We investigated the etiology of diarrhea and antimicrobial susceptibility pattern of bacterial pathogens and compared the results to previous work from the same clinical setting., Methods: A total of 381 cases and 176 controls were enrolled between March 2001 and 2003 in a case-control study. Enrollees were over age 18 years from high socioeconomic countries visiting or living in Nepal. Stool samples were assessed by microbiologic, molecular identification, and enzyme immunoassay (EIA) methods, and antimicrobial susceptibility was determined by disk diffusion. Risk factors were assessed by questionnaires., Results: At least one enteropathogen was identified in 263 of 381 (69%) cases and 47 of 176 (27%) controls (p ≤ 0.001). Pathogens significantly detected among cases were Campylobacter (17%), enterotoxigenic Escherichia coli (ETEC) (15%), Shigella (13%), and Giardia (11%). Cyclospora was detected only in cases (8%) mainly during monsoon season. Although 71% of Campylobacter isolates were resistant to ciprofloxacin, 80% of bacterial isolates overall were sensitive to either ciprofloxacin or azithromycin while 20% were intermediately sensitive or resistant. No bacterial isolates were resistant to both drugs., Conclusions: The most common pathogens causing TD in Nepal were Campylobacter, ETEC, and Shigella. Because resistance to fluoroquinolone or azithromycin was similar, one of these drugs could be used as empiric therapy for TD with the other reserved for treatment failures., (© 2010 International Society of Travel Medicine.)

Campylobacter jejuni is a foodborne pathogen and a leading cause of diarrhoea worldwide. It is believed that a cholera toxin-like toxin (CTLT) produced by C. jejuni may mediate watery diarrhoea. However, the production of a CTLT by C. jejuni is controversial. A cholera toxin gene (ctx) homologue has not been identified in Campylobacter species. We investigated the identity of the CT cross-reactive antigen from Campylobacter species previously and the results are reviewed here. Filtrates of C. jejuni grown in four different liquid media, reported to promote CTLT production, were tested by Chinese hamster ovary (CHO) cell elongation assay for functional toxin and for reactivity with CT antibody using GM1 ganglioside ELISA (GM1 ELISA) and immunoblotting. Protein sequence of the CT antibody-reactive band was determined by matrix-assisted laser desorption ionization-time of flight (MALDI TOF-TOF). Non-jejuni species (C. coli, C. lari, C. foetus, C. hyointestinalis and C. upsaliensis) were investigated by CHO cell assay and immunoblotting. Filtrates from seven C. jejuni reference strains reported to produce CTLT and from 80 clinical strains were negative in the CHO cell assay. However, filtrates from three reference strains and 16 clinical strains were positive by GM1 ELISA. All strains irrespective of GM1 ELISA reactivity, possessed a 53-kDa protein which reacted with CT antibody by immunoblotting. This band was identified as the major outer membrane protein (PorA) of C. jejuni. CT antibody reacted with a C. jejuni recombinant PorA on immunoblotting. All non-C. jejuni strains were negative by CHO cell assay, but the common 53-kDa proteins reacted with CT antibody on immunoblots. The cross-reactivity of PorAs of Campylobacter species with CT may lead to the erroneous conclusion that Campylobacter species produce a functional CTLT.

Campylobacter concisus has garnered increasing attention due to its association with intestinal disease, thus, the pathogenic potential of strains isolated from different intestinal diseases was investigated. A method to isolate C. concisus was developed and the ability of eight strains from chronic and acute intestinal diseases to adhere to and invade intestinal epithelial cells was determined. Features associated with bacterial invasion were investigated using comparative genomic analyses and the effect of C. concisus on host protein expression was examined using proteomics. Our isolation method from intestinal biopsies resulted in the isolation of three C. concisus strains from children with Crohn's disease or chronic gastroenteritis. Four C. concisus strains from patients with chronic intestinal diseases can attach to and invade host cells using mechanisms such as chemoattraction to mucin, aggregation, flagellum-mediated attachment, "membrane ruffling", cell penetration and damage. C. concisus strains isolated from patients with chronic intestinal diseases have significantly higher invasive potential than those from acute intestinal diseases. Investigation of the cause of this increased pathogenic potential revealed a plasmid to be responsible. 78 and 47 proteins were upregulated and downregulated in cells infected with C. concisus, respectively. Functional analysis of these proteins showed that C. concisus infection regulated processes related to interleukin-12 production, proteasome activation and NF-κB activation. Infection with all eight C. concisus strains resulted in host cells producing high levels of interleukin-12, however, only strains capable of invading host cells resulted in interferon-γ production as confirmed by ELISA. These findings considerably support the emergence of C. concisus as an intestinal pathogen, but more significantly, provide novel insights into the host immune response and an explanation for the heterogeneity observed in the outcome of C. concisus infection. Moreover, response to infection with invasive strains has substantial similarities to that observed in the inflamed mucosa of Crohn's disease patients.

Campylobacter concisus infections of the gastrointestinal tract can be accompanied by diarrhea and inflammation, whereas colonization of the human oral cavity might have a commensal nature. We focus on the pathophysiology of C. concisus and the effects of different clinical oral and fecal C. concisus strains on human HT-29/B6 colon cells. Six oral and eight fecal strains of C. concisus were isolated. Mucus-producing HT-29/B6 epithelial monolayers were infected with the C. concisus strains. Transepithelial electrical resistance (R(t)) and tracer fluxes of different molecule size were measured in Ussing chambers. Tight junction (TJ) protein expression was determined by Western blotting, and subcellular TJ distribution was analyzed by confocal laser-scanning microscopy. Apoptosis induction was examined by TUNEL-staining and Western blot of caspase-3 activation. All strains invaded confluent HT-29/B6 cells and impaired epithelial barrier function, characterized by a time- and dose-dependent decrease in R(t) either after infection from the apical side but even more from the basolateral compartment. TJ protein expression changes were sparse, only in apoptotic areas of infected monolayers TJ proteins were redistributed. Solely the barrier-forming TJ protein claudin-5 showed a reduced expression level to 66±8% (P<0.05), by expression regulation from the gene. Concomitantly, Lactate dehydrogenase release was elevated to 3.1±0.3% versus 0.7±0.1% in control (P<0.001), suggesting cytotoxic effects. Furthermore, oral and fecal C. concisus strains elevated apoptotic events to 5-fold. C. concisus-infected monolayers revealed an increased permeability for 332 Da fluorescein (1.74±0.13 vs. 0.56±0.17 10(-6) cm/s in control, P<0.05) but showed no difference in permeability for 4 kDa FITC-dextran (FD-4). The same was true in camptothecin-exposed monolayers, where camptothecin was used for apoptosis induction.In conclusion, epithelial barrier dysfunction by oral and fecal C. concisus strains could mainly be assigned to apoptotic leaks together with moderate TJ changes, demonstrating a leak-flux mechanism that parallels the clinical manifestation of diarrhea.

Background: Campylobacter concisus and other non-Campylobacter jejuni Campylobacter species have been implicated in the initiation of gastrointestinal diseases. In the present study, we investigated the interaction between these bacteria and the human intestinal epithelium and immune cells., Methods: The ability of C. concisus, Campylobacter showae, Campylobacter hominis, and Bacteroides ureolyticus to invade epithelial cells was examined using scanning electron microscopy and gentamicin protection assays. Proinflammatory cytokines generated by epithelial and immune cells in response to these bacteria were determined by enzyme-linked immunosorbent assay. Ussing Chamber, immunofluorescent stain, and Western blot were used to further elucidate the impact of C. concisus on intestinal barrier integrity and functions., Results: Attachment of non-C. jejuni Campylobacter species to Caco-2 or HT-29 cells was mediated by flagellum-dependent and/or -independent processes. C. concisus was able to invade Caco-2 cells, generate a membrane-ruffling effect on the epithelial surface on entry, and damage epithelial barrier functions by preferential attachment to the cell-cell junctions. Proinflammatory cytokine profiles exhibited by epithelial cells, monocytes, and macrophages in response to C. concisus and other non-C. jejuni Campylobacter species were species and strain specific., Conclusions: These findings demonstrate that C. concisus and other non-C. jejuni Campylobacter species may play a role in initiating gastrointestinal diseases.

To determine the virulence factors of Mexican wild-type strains of Campylobacter jejuni and Campylobacter coli, 31 wild-type strains were isolated from food and from humans. The production of cytolethal distending toxin and the adherence and invasion capabilities of these strains were assayed in Vero cells. Hard agar plugs with repellents and attractants were used to examine chemotaxis. Mueller-Hinton agar with supplements was used for motility analysis and to measure hemolytic activity. Nine strains of C. jejuni and eight strains of C. coli exhibited motility, most within a diameter of 2 to 13 mm. Most of the strains reacted to the repellent compounds analyzed, and α- and β-like hemolysis and cytotoxicity in Vero cells were observed for all strains. Isolates adhered to and invaded Vero cells to various degrees. Although strains of C. jejuni exhibited stronger adherence but less invasion compared with strains of C. coli, the difference was not significant (P > 0.05). The strains of C. jejuni and C. coli isolated from food and from patients in Mexico could have major impacts on public health.

Background: Campylobacteriosis is the most frequently reported zoonosis in the EU and the epidemiology of sporadic campylobacteriosis, especially the routes of transmission, is to a great extent unclear. Poultry easily become colonised with Campylobacter spp., being symptom-less intestinal carriers. Earlier it was estimated that internationally between 50% and 80% of the cases could be attributed to chicken as a reservoir. In a Norwegian surveillance programme all broiler flocks under 50 days of age were tested for Campylobacter spp. The aim of the current study was to identify simultaneous local space-time clusters each year from 2002 to 2007 for human cases of campylobacteriosis and for broiler flocks testing positive for Campylobacter spp. using a multivariate spatial scan statistic method. A cluster occurring simultaneously in humans and broilers could indicate the presence of common factors associated with the dissemination of Campylobacter spp. for both humans and broilers., Results: Local space-time clusters of humans and broilers positive for Campylobacter spp. occurring simultaneously were identified in all investigated years. All clusters but one were identified from May to August. Some municipalities were included in clusters all years., Conclusions: The simultaneous occurrence of clusters of humans and broilers positive for Campylobacter spp. combined with the knowledge that poultry meat has a nation-wide distribution indicates that campylobacteriosis cases might also be caused by other risk factors than consumption and handling of poultry meat.Broiler farms that are positive could contaminate the environment with further spread to new broiler farms or to humans living in the area and local environmental factors, such as climate, might influence the spread of Campylobacter spp. in an area. Further studies to clarify the role of such factors are needed.

Multiple transmission pathways exist for many waterborne diseases, including cholera, Giardia, Cryptosporidium, and Campylobacter. Theoretical work exploring the effects of multiple transmission pathways on disease dynamics is incomplete. Here, we consider a simple ODE model that extends the classical SIR framework by adding a compartment (W) that tracks pathogen concentration in the water. Infected individuals shed pathogen into the water compartment, and new infections arise both through exposure to contaminated water, as well as by the classical SIR person-person transmission pathway. We compute the basic reproductive number ([Symbol: see text](0)), epidemic growth rate, and final outbreak size for the resulting "SIWR" model, and examine how these fundamental quantities depend upon the transmission parameters for the different pathways. We prove that the endemic disease equilibrium for the SIWR model is globally stable. We identify the pathogen decay rate in the water compartment as a key parameter determining when the distinction between the different transmission routes in the SIWR model is important. When the decay rate is slow, using an SIR model rather than the SIWR model can lead to under-estimates of the basic reproductive number and over-estimates of the infectious period.

The prevalence of virulence and cytolethal distending toxin (CDT) genes and the cytotoxic activity in Vero and HEp-2 cells was estimated in 29 Campylobacter jejuni and 36 Campylobacter coli from foods, animals and humans isolates. All C. jejuni showed flaA, cadF, cdtA, cdtB, cdtC and cdt cluster genes fragments, except for ceuE (86.2%) and cdt genes (93.1%). Amongst C. coli strains, a lower prevalence of ceuE gene (83.3%) was detected than that for cdtA, cdtB, cdtC genes (97.2%), cdt gene cluster (94.4%) and cdt genes (86.1%); whereas flaA and cadF genes were amplified in all isolates. Despite the high prevalence of CDT genes only 8 (27.6%) C. jejuni and 1 (2.8%) C. coli showed evidence for cytotoxin production in HEp-2 cells. However, how CDT positive and CDT negative strains differ in their biological properties remains unknown, but the relative higher prevalence of cytotoxicity in C. jejuni could be consistent with its predominant epidemiological role in human infections., ((c) 2009 Elsevier Ltd. All rights reserved.)

The effect of growth phase on the adherence to and invasion of Caco-2 epithelial cells by five strains of Campylobacter was studied. No significant differences were observed between the behaviors in the exponential or stationary phases for the most stationary-phase tolerant strains (C. jejuni 118 and C. coli LP2), while the strains that produced a greater reduction in the viability in the stationary phase (C. jejuni 11351, C. jejuni 11168 and C. jejuni LP1), also presented reduced adherence to and invasion of Caco-2 cells. In order to find a possible explanation for the observed differences, the presence of putative virulence factors was studied in the analyzed strains. In spite of the fact that C. jejuni 118 and C. jejuni 11168 strains showed a different adherence to and invasion of Caco-2 cells behavior, they posses identical alleles for ciaB, cadF, and pldA loci. From the virulence factors analyzed, only the flaA locus was different among both strains., ((c) 2010 Elsevier B.V. All rights reserved.)

The persistence of naturally occurring campylobacteria in aerobic compost constructed of manure from beef cattle that were administered chlortetracycline and sulfamethazine (AS700) or from cattle not administered antibiotics (control) was examined. Although there were no differences in population sizes of heterotrophic bacteria, the temperature of AS700 compost was more variable and did not become as high as that of control compost. There were significant differences in water content, total carbon (C), total nitrogen (N), and electrical conductivity but not in the C/N ratio or pH between the two compost treatments. Campylobacteria were readily isolated from pen manure, for up to day 15 from control compost, and throughout the active phase of AS700 compost. Campylobacter DNA (including Campylobacter coli, Campylobacter fetus, Campylobacter hyointestinalis, and Campylobacter jejuni) was detected over the ca. 10-month composting period, and no reductions in quantities of C. jejuni DNA were observed over the duration of the active phase. The utilization of centrifugation in combination with ethidium monoazide (EMA) significantly reduced (>90%) the amplification of C. jejuni DNA that did not originate from cells with intact cell membranes. No differences were observed in the frequency of Campylobacter DNA detection between EMA- and non-EMA-treated samples, suggesting that Campylobacter DNA amplified from compost was extracted from cells with intact cell membranes (i.e., from viable cells). The findings of this study indicate that campylobacteria excreted in cattle feces persist for long periods in compost and call into question the common belief that these bacteria do not persist in manure.

CmeABC, a multidrug efflux system in Campylobacter jejuni, plays an important role in the resistance to different antimicrobials and toxic compounds. Although this efflux system has been well characterized in C. jejuni and to a less extent in C. coli, it is unknown if CmeABC homologs are functional in other Campylobacter spp. In this study, the cmeABC homologs were identified and functionally characterized in five Campylobacter species including C. jejuni, C. coli, C. lari, C. upsaliensis, and C. fetus. Our results indicated that cmeABC is present in all five Campylobacter spp. and the genomic organization of this efflux operon is similar among the Campylobacter spp. Insertional mutagenesis of cmeB increased the susceptibilities of all the five Campylobacter spp. to structurally diverse antimicrobials. Together, these results indicated that the CmeABC efflux system is conserved at both the genomic and functional levels in all five Campylobacter spp. examined in this study, further highlighting the significant role of CmeABC in Campylobacter pathobiology.

This study aims to investigate the genetic diversity of thermotolerant Campylobacter in commercial broiler flocks and in the environment of broiler farms in Belgium. Seven out of 18 investigated flocks became colonized during rearing. Fluorescent amplified fragment length polymorphism (FAFLP), pulsed field gel electrophoresis (PFGE), restriction fragment length polymorphism of the flagellin A gene (flaA-RFLP) and antimicrobial resistance profile (ARP) were used for typing of the isolates. By the combination of FAFLP and PFGE, 22 Campylobacter genotypes could be distinguished. Colonization was almost exclusively with Campylobacter jejuni and unique genotypes were found in each flock. Multiple genotypes were detected in the broilers of 3 flocks, either simultaneously or successively. In 5 flocks, strains that were resistant to at least one antibiotic (mostly tetracycline) were found. The presence of other broiler houses on the farm did not result in a higher probability of colonization. The nipple water was contaminated with the same genotype as the broilers, illustrating its importance for transmission of Campylobacter. The same genotype was detected in a water puddle and in the broiler flock during rearing in 3 flocks. Once, the same genotype was isolated from the ditch water shortly before it was detected in the broilers.

We hypothesized that patients coinfected with zoonotic Salmonella and Campylobacter were frailer than monoinfected Salmonella or Campylobacter patients. The study cohort included all first-time Salmonella/Campylobacter infections in Aarhus and North Jutland counties, Denmark, from 1991 through 2003. Data on comorbidity, hospitalization in relation to the Salmonella/Campylobacter infection, and 1-year mortality were obtained from electronic registries. Among 13,449 individuals, 114 (0.85%) had Salmonella/Campylobacter coinfection, 6567 (48.8%) had Salmonella monoinfection, and 6768 (50.3%) had Campylobacter monoinfection. There were no major differences in age, gender, comorbidity, hospitalization rates, 1-year mortality, or seasonal variation between coinfected patients on the one hand and each of the monoinfected patient groups on the other. The main difference was encountered between the Salmonella serotype distribution as 49.1% of coinfected patients versus 20.3% of monoinfected Salmonella patients had Salmonella serotypes other than Salmonella Enteritidis and Salmonella Typhimurium (odds ratio [95% confidence interval]: 4.07 [2.73-6.06]). In conclusion, Salmonella/Campylobacter coinfected patients were not frailer than monoinfected patients. The difference in Salmonella serotype distribution was compatible with a higher proportion of coinfections acquired during foreign travel.

Diarrhoea illnesses constitute a common cause of morbidity and mortality worldwide. In recent years, Campylobacter spp. has been recognized as the leading cause of bacterial enteritis in both developed and developing countries. The biology of Campylobacters as well as the mechanism by which they cause disease is yet to be fully explained. In addition, non-availability of fast and reliable diagnostic methodology and the growing trend of antibiotic resistance continue to pose significant challenges. The absence of national surveillance programs for campylobacteriosis, particularly in developing countries, makes it difficult to give an accurate picture of the true infection prevalence and the molecular epidemiology of isolates circulating in the populations, a situation which had hitherto existed in the Arabian Gulf region. However, in recent years, emerging data from studies in the Arabian Gulf region has not only enhanced our understanding of the epidemiology of Campylobacter both in humans and poultry in the region, but has also contributed to the overall understanding of the mechanism of Campylobacter enteritis, antibiotic resistance, and improved diagnostic approaches. In this review, we examine these emerging data from the Arabian Gulf region.

We report the findings of the first case-control study conducted in both the Republic of Ireland and Northern Ireland to determine risk factors for sporadic Campylobacter infections. A total of 197 cases and 296 case-nominated controls matched for age, were included. Based on Population Attributable Fraction (PAF), the most important risk factors were consuming chicken [adjusted matched (am) OR 6.8; 95%CI 2.1-21.9], consuming lettuce (amOR 3.3; 95%CI 1.5-7.1) and eating in takeaways (amOR=3.1; 95%CI 1.4-6.6). Contact with sheep (amOR=11; 95%CI 1.6-78), peptic ulcer (amOR=19; 95%CI 3.8-93.7), hiatus hernia (amOR=20.3; 95%CI 2.3-183.3), lower bowel problems (amOR=4.5; 95%CI 1.2-16.8) were also independently associated with infection. Mains water supply showed protective effect (amOR=0.2; 95 CI 0.1-0.9). The findings highlight the continued need for consumer food safety education and further control measures throughout the food chain on the island of Ireland.

Reactive arthritis (ReA) is an inflammatory arthritis that arises after certain gastrointestinal or genitourinary infections, representing a classic interplay between host and environment. It belongs to the group of arthritidies known as the spondyloarthropathies. The classic syndrome is a triad of symptoms, including the urethra, conjunctiva, and synovium; however, the majority of patients do not present with this triad. Diagnostic criteria for ReA exist, but data suggest new criteria are needed. Epidemiologic and prospective studies have been difficult to perform because of over-reliance on the complete classic triad of symptoms and the different terms and eponyms used. Studies assessing various treatment strategies are ongoing.

Infections with Campylobacter spp. occur as a result of consumption of live cells with food. In developing countries those infections are immensely common, particularly during early childhood and 5 to 10 cases can appear during the initial two years of life. The symptoms appear usually after 1-7 days from infection depending on the number of ingested cells and individual sensitivity. Characteristic symptoms of infections caused by Campylobacter spp. infrequently occurring jointly in the clinical form of the disease include: diarrhea, abdominal pain and increased temperature. In the majority of cases the disease is mild and lasts from 2 to 7 days. Usually Campylobacter are excreted with feces during a period of 7-21 days, sometimes even longer. Occasionally in the increased risk group dangerous complications may occur. They include: bacteremia, meningo-myelitis, neurological disturbances and reactive arthritis.

The use of defined primers for polymerase chain reaction (PCR) amplification of interspersed repetitive DNA elements present at distinct locations in prokaryotic genomes is referred to as repetitive element sequence based-polymerase chain reaction (rep-PCR). The initial discovery of repetitive extragenic palindromic (REP) elements occurred in the genomes of Escherichia coli and Salmonella. The family of REP elements is generally between 33 and 40 bp in length, has 500 to 1,000 copies per genome, and comprises about 1% of the bacterial genomes of E. coli or Salmonella. The amplified DNA fragments, when separated by electrophoresis, constitute a genomic fingerprint that can be employed for subspecies discrimination and strain delineation of bacteria and fungi. The application of rep-PCR to microbes has proven a discriminatory and reproducible tool for microbial subtype analyses and for microbial ecology investigations.

Campylobacteriosis is the most frequently reported zoonotic disease in humans within the European Union. The consumption of contaminated chicken meat is considered one of the main sources of human infection. Although there are no official data on the incidence of Campylobacter infection in Italy, the available studies suggest that this infection is a major problem also in Italy. The authors developed a simulation model to quantitatively estimate the expected annual number of human cases of campylobacteriosis in the Italian regions of Abruzzo and Molise, due to the cross-contamination during the handling of Campylobacter jejuni contaminated chicken meat in domestic kitchen. The authors considered two different models for the dose-response relationship, given their crucial effects on the model's outputs. The expected percentage of human population, experiencing Campylobacter gastroenteritis episodes every year in Abruzzo e Molise regions, varied between 0.8% and 1.8%, according to the dose-response model.

Aim: To infect mice with atypical Campylobacter concisus (C. concisus) for the first time., Methods: Three separate experiments were conducted in order to screen the ability of five clinical C. concisus isolates of intestinal origin and the ATCC 33237 type strain of oral origin to colonize and produce infection in immunocompetent BALB/cA mice. The majority of the BALB/cA mice were treated with cyclophosphamide prior to C. concisus inoculation to suppress immune functions. Inoculation of C. concisus was performed by the gastric route., Results: C. concisus was isolated from the liver, ileum and jejunum of cyclophosphamide-treated mice in the first experiment. No C. concisus strains were isolated in the two subsequent experiments. Mice infected with C. concisus showed a significant loss of body weight from day two through to day five of infection but this decreased at the end of the first week. Histopathological examination did not consistently find signs of inflammation in the gut, but occasionally microabscesses were found in the liver of infected animals., Conclusion: Transient colonization with C. concisus was observed in mice with loss of body weight. Future studies should concentrate on the first few days after inoculation and in other strains of mice.

Campylobacter concisus is an opportunistic pathogen commonly found in the human oral cavity. It has also been isolated from clinical sources including gastroenteritis cases. Both secreted and cell-associated hemolytic activities were detected in C. concisus strains isolated from children with gastroenteritis. The secreted hemolytic activity of C. concisus strains was labile and was detected in variable levels from fresh-culture filtrates only. In addition, another secreted hemolysin/cytotoxin with a molecular weight < 10 kDa was detected in a single C. concisus strain (RCH 12). A C. concisus genomic library, constructed from strain RCH 3 in Escherichia coli XL1-Blue, was screened for hemolytic clones. Subcloning and sequence analysis of selected hemolytic clones identified ORFs for genes that enhance hemolytic activity but do not appear to be related to any known hemolysin genes found in Gram-negative bacteria. In a previous study, a stable cell-associated hemolysin was identified as an outer-membrane phospholipase A (OMPLA) encoded by the pldA gene. In this study, we report cloning of the pldA gene of the clinical strain C. concisus RCH 3 and the complementation of phospholipase A activity in an E. coli pldA mutant.

Campylobacter jejuni isolates (n = 340) were collected from nine turkey flocks in three rotations (A, B, and C) at a newly established turkey production facility in North Dakota and at processing. Samples were collected at weeks 1, 4, 9, and 18, as well as at two stages on the processing line at the processing plant. Campylobacter was not isolated from the first flocks in the rotations (A1, B1, and C1), but was detected at week 18 in the second flock groupings and at week 9 in the third flock groupings. The cumulative increase in Campylobacter prevalence observed in each subsequent rotation was attributed to flock rotation through the brooder barn, in which each flock was housed for 4 weeks before moving to a finishing barn; the brooder was the only common building shared by all flocks in each grouping (A, B, and C). C. jejuni isolates recovered were analyzed for the presence of selected virulence genes; 100% of the isolates tested were positive for the flaA, pldA, and cadF genes; 99.7% of the isolates were positive for the cdtB, cdtC, and ciaB genes. The prevalence of the cdtA and cjp05 genes was much lower at 11.2 and 67.5%, respectively. Results of this study indicate flock rotation may increase Campylobacter prevalence; molecular characterization provided information about Campylobacter from a new turkey production facility.

Tetracycline (tet) resistance in Campylobacter isolated from organically raised broilers was investigated in this study. Two hundred forty-five samples from an organic broiler farm were collected weekly from the first week to the end of the production cycle, and they were cultured for thermophilic Campylobacter. Tetracycline resistance of these Campylobacter isolates was identified by the agar dilution method, whereas DNA fingerprinting profiles of tet-susceptible and tet-resistant strains were determined by pulsed-field gel electrophoresis (PFGE). None of the Campylobacter isolates from the third and the fourth week of the production period were resistant to tetracycline, whereas 66.7% of the isolates from the fifth week were resistant to this antibiotic. Although the prevalence of tetracycline resistance reached 100.0% during the sixth and seventh week, less than 34.0% of the isolates from the 10th week were resistant to this antimicrobial agent. In addition, only 13.8% of Campylobacter isolates from the intestinal tracts of these organically raised broilers were resistant to tetracycline. The presence of the tet(O) gene was detected in 98.9% of tet-resistant Campylobacter isolates, and tet-susceptible and tet-resistant Campylobacter strains showed distinct PFGE genotypes. The results suggest that the Campylobacter strains isolated from the early stage of the production were susceptible to tetracycline, but they were subsequently displaced by tet-resistant Campylobacter.

Escherichia coli (E. coli) O157:H7 is a common cause of bloody diarrhea in developed countries. The aim of this study was to determine whether E. coli O157:H7 is a possible pathogen of bloody diarrhea in southern Iran. Out of 719 children with diarrhea, 243 (34%) patients with positive occult blood took part in our study. The polyclonal antibody test and polymerase chain reaction (PCR) were used to identify E. coli O157:H7. Stool cultures showed enteropathogens in 107 patients (44%). Shigella (34.3%) was followed by E. coli (8.6%), campylobacter (2%) and salmonella (0.4%). None of the E. coli species was of O157:H7 serotype. Antibiotic sensitivity of shigella species was 100% to ceftriaxone, ciprofloxacin and ceftazidime, 94% to nalidixic acid and 13% to co-trimoxazole. The results of the study showed that E. coli O157:H7 is not a cause of bloody diarrhea in our area.

Faecal prevalence of gastrointestinal bacterial pathogens, including Campylobacter, Escherichia coli O157:H7, Salmonella, Shigella, Yersinia, as well as Arcobacter, were examined in 317 faecal specimens from 44 animal species in Belfast Zoological Gardens, during July-September 2006. Thermophilic campylobacters including Campylobacter jejuni, Campylobacter coli and Campylobacter lari, were the most frequently isolated pathogens, where members of this genus were isolated from 11 animal species (11 of 44; 25%). Yersinia spp. were isolated from seven animal species (seven of 44; 15.9%) and included, Yersinia enterocolitica (five of seven isolates; 71.4%) and one isolate each of Yersinia frederiksenii and Yersinia kristensenii. Only one isolate of Salmonella was obtained throughout the entire study, which was an isolate of Salmonella dublin (O 1,9,12: H g, p), originating from tiger faeces after enrichment. None of the animal species found in public contact areas of the zoo were positive for any gastrointestinal bacterial pathogens. Also, water from the lake in the centre of the grounds, was examined for the same bacterial pathogens and was found to contain C. jejuni. This study is the first report on the isolation of a number of important bacterial pathogens from a variety of novel host species, C. jejuni from the red kangaroo (Macropus rufus), C. lari from a maned wolf (Chrysocyon brachyurus), Y. kristensenii from a vicugna (Vicugna vicugna) and Y. enterocolitica from a maned wolf and red panda (Ailurus fulgens). In conclusion, this study demonstrated that the faeces of animals in public contact areas of the zoo were not positive for the bacterial gastrointestinal pathogens examined. This is reassuring for the public health of visitors, particularly children, who enjoy this educational and recreational resource.

A novel approach to the quantitative assessment of food-borne risks is proposed. The basic idea is to use Bayesian techniques in two distinct steps: first by constructing a stochastic core model via a Bayesian network based on expert knowledge, and second, using the data available to improve this knowledge. Unlike the Monte Carlo simulation approach as commonly used in quantitative assessment of food-borne risks where data sets are used independently in each module, our consistent procedure incorporates information conveyed by data throughout the chain. It allows "back-calculation" in the food chain model, together with the use of data obtained "downstream" in the food chain. Moreover, the expert knowledge is introduced more simply and consistently than with classical statistical methods. Other advantages of this approach include the clear framework of an iterative learning process, considerable flexibility enabling the use of heterogeneous data, and a justified method to explore the effects of variability and uncertainty. As an illustration, we present an estimation of the probability of contracting a campylobacteriosis as a result of broiler contamination, from the standpoint of quantitative risk assessment. Although the model thus constructed is oversimplified, it clarifies the principles and properties of the method proposed, which demonstrates its ability to deal with quite complex situations and provides a useful basis for further discussions with different experts in the food chain.

Purpose of Review: Molecular pathogenesis of Campylobacter jejuni has lagged behind that of other enteric pathogens. This review summarizes advances in the biology and pathogenesis of C. jejuni., Recent Findings: Multiple genome sequences have defined conserved and hypervariable loci in the C. jejuni genome. Interaction of C. jejuni with eukaryotic cells results in numerous signal transduction changes and release of proinflammatory cytokines. In-vivo models based on immune knockout mice have also revealed new information on pathogenesis., Summary: New information and new methods are available that should provide important tools to further understand pathogenesis of this elusive pathogen.

Campylobacter insulaenigrae is a novel species that has been recently only isolated from marine mammals. This is the first report of C. insulaenigrae causing enteritis and septicaemia in a patient with end-stage hepatic and renal disease.

Determining the survival of zoonotic pathogens in livestock manure and runoff is critical for understanding the environmental and public health risks associated with these wastes. The occurrence and persistence of the bacterial pathogens Escherichia coli O157:H7 and Campylobacter spp. in a passive beef cattle feedlot runoff control-vegetative treatment system were examined over a 26-mo period. Incidence of the protozoans Cryptosporidium spp. and Giardia spp. was also assessed. The control system utilizes a shallow basin to collect liquid runoff and accumulate eroded solids from the pen surfaces; when an adequate liquid volume is attained, the liquid is discharged from the basin onto a 4.5-ha vegetative treatment area (VTA) of bromegrass which is harvested as hay. Basin discharge transported E. coli O157, Campylobacter spp., and generic E. coli into the VTA soil, but without additional discharge from the basin, the pathogen prevalences decreased over time. Similarly, the VTA soil concentrations of generic E. coli initially decreased rapidly, but lower residual populations persisted. Isolation of Cryptosporidium oocysts and Giardia cysts from VTA samples was infrequent, indicating differences in sedimentation and/or transport in comparison to bacteria. Isolation of generic E. coli from freshly cut hay from VTA regions that received basin discharge (12 of 30 vs. 1 of 30 control samples) provided evidence for the risk of contamination; however, neither E. coli O157 or Campylobacter spp. were recovered from the hay following baling. This work indicates that the runoff control system is effective for reducing environmental risk by containing and removing pathogens from feedlot runoff.

Campylobacter jejuni and Campylobacter coli are among the major causes of diarrheal disease worldwide. The motility imparted by the polar flagella of these pathogens is required for colonization of the mucus lining of the gastrointestinal tract. However, recent studies have revealed a more complex role for flagella in Campylobacter pathogenesis that includes the ability to secrete non-flagellar proteins that modulate virulence and the co-regulation of secreted and non-secreted virulence factors with the flagella regulon. Campylobacter flagellins are heavily glycosylated and changes in glycan composition affect autoagglutination and microcolony formation on intestinal epithelial cells; these traits are associated with disease in an animal model. Here, these recent advances in our understanding of the multifaceted role of flagella in Campylobacter virulence are summarized.

Campylobacters are emerging as one of the most significant causes of human infections worldwide, and the role that waterfowl and the aquatic environment have in the spread of disease is beginning to be elucidated. On a world scale campylobacters are possibly the major cause of gastrointestinal infections. Campylobacters are common commensals in the intestinal tract of many species of wild birds, including waterfowl. They are also widely distributed in aquatic environments where their origins may include waterfowl as well as sewage effluents and agricultural runoff. Campylobacters have marked seasonal trends. In temperate aquatic environments they peak during winter, whereas spring-summer is the peak period for human infection. Campylobacter species may survive, and remain potentially pathogenic, for long periods in aquatic environments. The utility of bacterial fecal indicators in predicting the presence of campylobacters in natural waters is questionable. Viable but nonculturable Campylobacter cells may occur, but whether they have any role in the generation of outbreaks of campylobacteriosis is unclear. The routine detection of Campylobacter spp. in avian feces and environmental waters largely relies on conventional culture methods, while the recognition of a particular species or strain is based on serotyping and increasingly on molecular methods. Thus, PCR combined with selective enrichment enhances the detection of campylobacters in water and feces, while DNA sequencing facilitates recognition of particular species and strains.

Campylobacter jejuni is a major cause of bacterial food-borne infection in the industrial world. There is evidence that C. jejuni is present in eggs and hatchery fluff, opening the possibility for vertical transmission from hens to progeny. Poultry operations in Iceland provide an excellent opportunity to study this possibility, since breeding flocks are established solely from eggs imported from grandparent flocks in Sweden. This leaves limited opportunity for grandparents and their progeny to share isolates through horizontal transmission. While Campylobacter was not detected in all grandparent flocks, 13 of the 16 egg import lots consisted of eggs gathered from one or more Campylobacter-positive grandparent flocks. No evidence of Campylobacter was found by PCR in any of the 10 relevant quarantine hatchery fluff samples examined, and no Campylobacter was isolated from the parent birds through 8 weeks, while they were still in quarantine rearing facilities. After the birds were moved to less biosecure rearing facilities, Campylobacter was isolated, and 29 alleles were observed among the 224 isolates studied. While three alleles were found in both Sweden and Iceland, in no case was the same allele found both in a particular grandparent flock and in its progeny. We could find no evidence for vertical transmission of Campylobacter to the approximately 60,000 progeny parent breeders that were hatched from eggs coming from Campylobacter-positive grandparent flocks. If vertical transmission is occurring, it is not a significant source for the contamination of chicken flocks with Campylobacter spp.

Recent outbreaks of Escherichia coli O157:H7, Campylobacter, and Cryptosporidium have heightened awareness of risks associated with contaminated water supply. The objectives of this research were to describe the incidence and distribution of waterborne disease outbreaks in Canada in relation to preceding weather conditions and to test the association between high impact weather events and waterborne disease outbreaks. We examined extreme rainfall and spring snowmelt in association with 92 Canadian waterborne disease outbreaks between 1975 and 2001, using case-crossover methodology. Explanatory variables including accumulated rainfall, air temperature, and peak stream flow were used to determine the relationship between high impact weather events and the occurrence of waterborne disease outbreaks. Total maximum degree-days above 0 degrees C and accumulated rainfall percentile were associated with outbreak risk. For each degree-day above 0 degrees C the relative odds of an outbreak increased by a factor of 1.007 (95% confidence interval [CI] = 1.002 - 1.012). Accumulated rainfall percentile was dichotomized at the 93rd percentile. For rainfall events greater than the 93rd percentile the relative odds of an outbreak increased by a factor of 2.283 (95% [CI] = 1.216 - 4.285). These results suggest that warmer temperatures and extreme rainfall are contributing factors to waterborne disease outbreaks in Canada. This could have implications for water management and public health initiatives.

Campylobacter curvus was isolated from blood cultures of a patient with liver abscesses. Bacterial identification involved Gram staining, biochemical analysis, gas-liquid chromatography, and 16S rRNA sequencing. The difficulty in isolation, identification, and growth of the species confirms previous work that these organisms may be overlooked by conventional detection methods.

In 2004 the Food and Consumer Product Safety Authority (VWA) investigated the hygiene and hygiene facilities on 125 children's farms. In general, both the level of hygiene and the availability of hygiene facilities were good. A previous investigation, carried out in 2002, had highlighted a number of points for improvement, such as the need to improve hand-washing facilities. While the situation was better in 2004, it still did not meet the standard laid down by the VWA. The VWA aspires to achieve 100% implementation of the requirement that children's farms have a Code for Hygiene and an information board. Investigation of faecal samples collected in 2002 showed the presence of STEC O157 on 13 (10.2%) of the visited farms, Salmonella spp. on 19 (14.5%) and Campylobacter spp. on 74 (56.6%). These results show that there is a real risk of becoming infected with a zoonotic pathogen when visiting a children's farm. This emphasizes the importance of strict adherence to hygiene measures by workers and visitors on children's farms in The Netherlands.

In this study comprising isolates from 2001 to 2003, resistance was considerably more widespread among Campylobacter jejuni from humans infected abroad than infected within Norway. The discrepancy was particularly notable for fluoroquinolone resistance (67.4% vs. 6.5%). This is probably a reflection of a low resistance prevalence in Norwegian broiler isolates (1.2% fluoroquinolone resistant).

The FDA Center for Veterinary Medicine (CVM) (Bartholomew et al., 2005) recently proposed an approach to risk management based on the linear modeling framework: Risk = K x Exposure. They suggest that, once K has been estimated from historical data, it can be used to predict how limiting future exposure will reduce future risk. They illustrate the approach for fluoroquinolone-resistant campylobacter in chicken. However, despite its appealing simplicity, the proposed approach confuses a possibly meaningless descriptive statistical ratio with a valid predictive causal relation. In general, the historical ratio K = (Risk/Exposure) may not predict how changing future exposures will affect future risks, and hence it does not necessarily provide an appropriate guide to current risk management actions. We identify several limitations of the proposed framework, including omission of frequency and severity of human health harm in quantifying "Risk" and omission of microbial load from "Exposure." Finally, we show that an extended linear modeling approach that considers impacts of changing animal antibiotic use on susceptible as well as on resistant bacteria is consistent with the conclusion that reducing "Exposure" can greatly increase "Risk."

Campylobacter concisus has been as frequently isolated from human diarrhea as the important enteropathogen Campylobacter jejuni, but it also occurs in the feces of healthy individuals. The role of C. concisus in human disease has been difficult to determine, since the species comprises at least two phenotypically indistinguishable but genetically distinct taxa (i.e., genomospecies) that may vary in pathogenicity. We examined 62 C. concisus strains by amplified fragment length polymorphism (AFLP) profiling and correlated the results with clinical data. All C. concisus strains gave unique AFLP profiles, and numerical analysis of these data distributed the strains among four clusters. The clustering was of taxonomic significance: two clusters contained, respectively, the type strain (of oral origin) and a reference strain (from diarrhea) of each of the known genomospecies. Genomospecies 2 strains were more frequently isolated from immunocompetent patients and/or patients without concomitant infections that presented with fever, chronic diarrhea, and gut inflammation than was genomospecies 1, clustering with the type strain of oral origin. Bloody diarrhea was recorded only with C. concisus genomospecies 2 infections. We identified two additional C. concisus genomospecies: genomospecies 3 comprised a single strain from an immunocompetent patient, and genomospecies 4 contained five isolates from severely immunodeficient patients, i.e., organ transplantation recipients or those with hematological malignancies. All genomospecies 4 strains were of the same protein profile group and failed to react with a C. concisus species-specific PCR assay based on 23S rRNA gene sequences: the taxonomic position of this group requires closer investigation. Campylobacter concisus is genetically and taxonomically diverse and contains at least four distinct genomospecies that may exhibit differences in their spectra of virulence potential.

Only about half the cases of intestinal infectious disease have a routinely detectable causative agent diagnosed. Increasingly, evidence indicates that Campylobacter species other than C. jejuni and C. coli are associated with such cases. However, evidence is less clear, from epidemiological studies, for the pathogenic nature of these unusual campylobacters. This is particularly true for organisms like C. concisus and is compounded by poor methods for routine recovery and identification. Moreover, the application of typing methods for C. concisus has indicated a heterogeneous population and there is preliminary evidence to suggest differences in the pathogenic potential of strain types. However, considerable further work is needed with more discriminatory genotyping methods, before accurate assessment of the risk of C. concisus infection to human health can be determined.

Oral Campylobacter species are rarely reported to cause extraoral infections. Here we present three cases of extraoral abscess caused by an oral Campylobacter sp. and a Streptococcus sp. The Campylobacter species were all isolated anaerobically and identified by sequencing analysis of the 16S rRNA gene. The cases included a breast abscess caused by Campylobacter rectus and a non-group A beta-hemolytic streptococcus in a patient with lymphoma, a liver abscess caused by Campylobacter curvus and an alpha-hemolytic streptococcus in a patient with complicated ovarian cancer, and a postobstructive bronchial abscess caused by C. curvus and group C beta-hemolytic Streptococcus constellatus in a patient with lung cancer. The abscesses were drained or resected, and the patients were treated with antibiotics with full resolution of the lesions. The C. curvus cases are likely the first reported infections by this organism, and the C. rectus case represents the second such reported extraoral infection.

The use of fluoroquinolones (FQs) in poultry production is an important issue in public health today. In February 2002, two prominent U.S. poultry companies pledged to stop using FQs for flock-wide treatment. One year later, we began a survey of Campylobacter isolates on chicken products from these two companies and from two producers claiming total abstention from antibiotic use. Using both standard isolation methods and new methods modified to enhance detection of FQ-resistant Campylobacter, we compared rates of FQ-resistant Campylobacter among these products. Four major findings were drawn from this study: a) antibiotic-free brands were not more likely to be contaminated with Campylobacter; b) a high percentage of products from the two conventional brands were contaminated with FQ-resistant Campylobacter (43 and 96%); c) these conventional brands had significantly higher odds of carrying resistant strains compared with antibiotic-free products; and d) supplementing media with FQs increased the sensitivity of detecting FQ-resistant strains among mixed populations of Campylobacter, thus reducing a bias toward underestimating the prevalence of FQ-resistant Campylobacter on samples. These results suggest that FQ resistance may persist in the commercial poultry environment in the absence of FQ-selective pressure and that these strains contaminate a larger proportion of foods than reported previously.