Kalupahana R.S.,University of Peradeniya |
Kottawatta K.S.A.,University of Peradeniya |
Kanankege K.S.T.,University of Peradeniya |
Van Bergen M.A.P.,Central Veterinary Institute of Wageningen UR |
And 5 more authors.
Applied and Environmental Microbiology | Year: 2013
The onset and prevalence of Campylobacter colonization in broilers and layers at commercial farms with low biosecurity in tropical climates were tested. Despite the presence of positive animals at the same farms, the broiler flocks tested negative until, on average, 21 days. Prelaying flocks showed a higher prevalence than laying flocks. © 2013, American Society for Microbiology.
Jore S.,National Veterinary Institute |
Viljugrein H.,National Veterinary Institute |
Brun E.,National Veterinary Institute |
Heier B.T.,Norwegian Institute of Public Health |
And 13 more authors.
Preventive Veterinary Medicine | Year: 2010
The objective of this study was to examine incidences of Campylobacter in broilers and humans, and to describe seasonal variation and long-term trends by comparing longitudinal surveillance data in six Northern European countries (Denmark, Finland, Iceland, Norway, Sweden and the Netherlands). Due to high degree of seasonality and autocorrelation, seasonally adjusted (de-seasonalized) and trend adjusted data (de-trended) were used for comparing incidences within and between the six countries. De-seasonalized time series were obtained by fitting the incidence time series to mean monthly temperature and then removing this effect from the data. Long-term trends were fitted to the de-seasonalized time series. The incidence of Campylobacter colonization in broiler flocks and incidence of campylobacteriosis in humans showed a concordant seasonality for all the countries. There was a strong association between the incidence in both broilers and humans in a given month and the mean temperature of the northern hemisphere in the same month, as well as the preceding month, as shown by the cross-correlations and the chosen Generalized Additive Model. Denmark and Sweden showed a steadily decreasing trend for Campylobacter in broilers and human campylobacteriosis in the period 2001-2007. In Iceland, there was a decreasing trend for campylobacteriosis in humans from 1999 to 2007, whilst the broiler trend for Campylobacter was stable from 2001 to 2004, then falling thereafter. In Norway, the human campylobacteriosis trend showed a steady increase throughout the period. On the other hand, the Norwegian broiler trend for Campylobacter showed a decrease from 2001 until 2004, but was thereafter stable. There was no significant decrease or increase in incidence for human campylobacteriosis in the Netherlands, and the trend for Campylobacter in broilers was close to stable. The seasonality seen in broiler and human closely follows the temperature, and was probably caused, at least partly, by temperature related factors. © 2009 Elsevier B.V. All rights reserved.
Dingle K.E.,University of Oxford |
Blaser M.J.,New York University |
Tu Z.-C.,New York University |
Pruckler J.,Enteric Diseases Laboratory Branch |
And 8 more authors.
Journal of Clinical Microbiology | Year: 2010
Reptile Campylobacter fetus isolates and closely related strains causing human disease were characterized by multilocus sequence typing. They shared ∼90% nucleotide sequence identity with classical mammalian C. fetus, and there was evidence of recombination among members of these two groups. The reptile group represents a possible separate genomospecies capable of infecting humans. Copyright © 2010, American Society for Microbiology. All Rights Reserved.
Gaasbeek E.J.,Central Veterinary Institute of Wageningen UR |
Gaasbeek E.J.,University Utrecht |
Wagenaar J.A.,Central Veterinary Institute of Wageningen UR |
Wagenaar J.A.,University Utrecht |
And 8 more authors.
Journal of Bacteriology | Year: 2010
The species Campylobacter jejuni is naturally competent for DNA uptake; nevertheless, nonnaturally transformable strains do exist. For a subset of strains we previously showed that a periplasmic DNase, encoded by dns, inhibits natural transformation in C. jejuni. In the present study, genetic factors coding for DNase activity in the absence of dns were identified. DNA arrays indicated that nonnaturally transformable dns-negative strains contain putative DNA/RNA nonspecific endonucleases encoded by CJE0566 and CJE1441 of strain RM1221. These genes are located on C. jejuni integrated elements 2 and 4. Expression of CJE0566 and CJE1441 from strain RM1221 and a homologous gene from strain 07479 in DNase-negative Escherichia coli and C. jejuni strains indicated that these genes code for DNases. Genetic transfer of the genes to a naturally transformable C. jejuni strain resulted in a decreased efficiency of natural transformation. Modeling suggests that the C. jejuni DNases belong to the Serratia nuclease family. Overall, the data indicate that the acquisition of prophageencoded DNA/RNA nonspecific endonucleases inhibits the natural transformability of C. jejuni through hydrolysis of DNA. Copyright © 2010, American Society for Microbiology. All Rights Reserved.
Doorduyn Y.,National Institute of Public Health and the Environment |
Van Den Brandhof W.E.,National Institute of Public Health and the Environment |
Van Duynhoven Y.T.H.P.,National Institute of Public Health and the Environment |
Breukink B.J.,National Institute of Public Health and the Environment |
And 4 more authors.
Epidemiology and Infection | Year: 2010
A case-control study comprising 1315 Campylobacter jejuni cases, 121 Campylobacter coli cases and 3409 frequency-matched controls was conducted in The Netherlands in 2002-2003. Risk factors for both C. jejuni and C. coli enteritis were consumption of undercooked meat and barbecued meat, ownership of cats and use of proton pump inhibitors. Consumption of chicken was a predominant risk factor for C. jejuni enteritis, but many additional risk factors were identified. Unique risk factors for C. coli infections were consumption of game and tripe, and swimming. Contact with farm animals and persons with gastroenteritis were predominant risk factors for C. jejuni enteritis in young children (0-4 years). Important risk factors for the elderly (60 years) were eating in a restaurant, use of proton pump inhibitors and having a chronic intestinal illness. Consumption of chicken in spring, steak tartare in autumn and winter and barbecued meat in rural areas showed strong associations with C. jejuni infections. This study illustrates that important differences in risk factors exist for different Campylobacter spp. and these may differ dependent on age, season or degree of urbanization. Copyright © 2010 Cambridge University Press.
van der Graaf-van Bloois L.,University Utrecht |
van der Graaf-van Bloois L.,Collaborating Center for Campylobacter |
van Bergen M.A.P.,Central Veterinary Institute of Wageningen UR |
van Bergen M.A.P.,Collaborating Center for Campylobacter |
And 10 more authors.
Journal of Microbiological Methods | Year: 2013
Phenotypic differentiation between Campylobacter fetus (C. fetus) subspecies fetus and C. fetus subspecies venerealis is hampered by poor reliability and reproducibility of biochemical assays. AFLP (amplified fragment length polymorphism) and MLST (multilocus sequence typing) are the molecular standards for C. fetus subspecies identification, but these methods are laborious and expensive. Several PCR assays for C. fetus subspecies identification have been described, but a reliable comparison of these assays is lacking.The aim of this study was to evaluate the most practical and routinely implementable published PCR assays designed for C. fetus species and subspecies identification. The sensitivity and specificity of the assays were calculated by using an extensively characterized and diverse collection of C. fetus strains. AFLP and MLST identification were used as reference. Two PCR assays were able to identify C. fetus strains correctly at species level. The C. fetus species identification target, gene nahE, of one PCR assay was used to develop a real-time PCR assay with 100% sensitivity and 100% specificity, but the development of a subspecies venerealis specific real-time PCR (ISC. fe1) failed due to sequence variation of the target insertion sequence and prevalence in other Campylobacter species. None of the published PCR assays was able to identify C. fetus strains correctly at subspecies level. Molecular analysis by AFLP or MLST is still recommended to identify C. fetus isolates at subspecies level. © 2013 Elsevier B.V.
van Bunnik B.A.D.,Central Veterinary Institute of Wageningen UR |
van Bunnik B.A.D.,Wageningen University |
Katsma W.E.A.,Central Veterinary Institute of Wageningen UR |
Wagenaar J.A.,Central Veterinary Institute of Wageningen UR |
And 5 more authors.
Preventive Veterinary Medicine | Year: 2012
In this study the effect of acidification of the drinking water of broiler chickens on both direct and indirect transmission of Campylobacter was evaluated. In the direct transmission experiment both susceptible and inoculated animals were housed together. In the indirect transmission experiment the susceptible animals were spatially separated from the inoculated animals and no direct animal to animal contact was possible. The transmission parameter β was estimated for the groups supplied with acidified drinking water and for the control groups. The results showed that acidification of the drinking water had no effect on direct transmission (β=3.7day-1 for both control and treatment). Indirect transmission however was influenced by acidification of the drinking water. A significant decrease in transmission was observed (p<0.05), with control vs. treatment point estimates being β=0.075day-1 vs. β=0.011day-1.Apart from providing quantitative estimations of both direct and indirect transmission of . Campylobacter in broilers, this study also demonstrates the use of an experimental setup for indirect transmission of . Campylobacter between broilers to assess the efficacy of candidate measures to reduce transmission. © 2012 Elsevier B.V.
Ang C.W.,VU University Amsterdam |
Ang C.W.,Erasmus Medical Center |
Dijkstra J.R.,Central Veterinary Institute of Wageningen UR |
de Klerk M.A.,Erasmus Medical Center |
And 8 more authors.
PLoS ONE | Year: 2010
Background: Anti-ganglioside antibodies with a pathogenic potential are present in C. jejuni-associated Guillain-Barré syndrome (GBS) patients and are probably induced by molecular mimicry. Immunization studies in rabbits and mice have demonstrated that these anti-ganglioside antibodies can be induced using purified lipo-oligosaccharides (LOS) from C. jejuni in a strong adjuvant. Methodology/Principal Findings: To investigate whether natural colonization of chickens with a ganglioside-mimicking C. jejuni strain induces an anti-ganglioside response, and to investigate the diversity in anti-ganglioside response between and within genetically different chicken lines, we orally challenged chickens with different C. jejuni strains. Oral challenge of chickens with a C. jejuni strain from a GBS patient, containing a LOS that mimics ganglioside GM1, induced specific IgM and IgG anti-LOS and anti-GM1 antibodies. Inoculation of chickens with the Penner HS:3 serostrain, without a GM1-like structure, induced anti-LOS but no anti-ganglioside antibodies. We observed different patterns of anti-LOS/ganglioside response between and within the five strains of chickens. Conclusions: Natural infection of chickens with C. jejuni induces anti-ganglioside antibodies. The production of antibodies is governed by both microbial and host factors. © 2010 Ang et al.
Gilbert M.J.,University Utrecht |
Kik M.,University Utrecht |
Timmerman A.J.,University Utrecht |
Severs T.T.,University Utrecht |
And 6 more authors.
PLoS ONE | Year: 2014
Campylobacter, Arcobacter, and Helicobacter species have been isolated from many vertebrate hosts, including birds, mammals, and reptiles. Multiple studies have focused on the prevalence of these Epsilonproteobacteria genera in avian and mammalian species. However, little focus has been given to the presence within reptiles, and their potential zoonotic and pathogenic roles. In this study, occurrence, diversity, and host association of intestinal Epsilonproteobacteria were determined for a large variety of reptiles. From 2011 to 2013, 444 cloacal swabs and fecal samples originating from 417 predominantly captive-held reptiles were screened for Epsilonproteobacteria. Campylobacter, Arcobacter , and Helicobacter genus specific PCRs were performed directly on all samples. All samples were also cultured on selective media and screened for the presence of Epsilonproteobacteria. Using a tiered approach of AFLP, atpA, and 16S rRNA sequencing, 432 Epsilonproteobacteria isolates were characterized at the species level. Based on PCR, Campylobacter, Arcobacter, and Helicobacter were detected in 69.3% of the reptiles; 82.5% of the chelonians, 63.8% of the lizards, and 58.0% of the snakes were positive for one or more of these genera. Epsilonproteobacteria were isolated from 22.1% of the reptiles and were isolated most frequently from chelonians (37.0%), followed by lizards (19.6%) and snakes (3.0%). The most commonly isolated taxa were Arcobacter butzleri, Arcobacter skirrowii, reptile-associated Campylobacter fetus subsp. testudinum, and a putative novel Campylobacter taxon. Furthermore, a clade of seven related putative novel Helicobacter taxa was isolated from lizards and chelonians. This study shows that reptiles carry various intestinal Epsilonproteobacteria taxa, including several putative novel taxa. © 2014 Gilbert et al.
Van Der Graaf-Van Bloois L.,University Utrecht |
Van Der Graaf-Van Bloois L.,Collaborating Center for Campylobacter |
Miller W.G.,U.S. Department of Agriculture |
Yee E.,U.S. Department of Agriculture |
And 6 more authors.
Journal of Clinical Microbiology | Year: 2014
Classifications of the Campylobacter fetus subspecies fetus and venerealis were first described in 1959 and were based on the source of isolation (intestinal versus genital) and the ability of the strains to proliferate in the g enital tract of cows. Two phenotypic assays (1% glycine tolerance and H2S production) were described to differentiate the subspecies. Multiple molecular assays have been applied to differentiate the C. fetus subspecies, but none of these tests is consistent with the phenotypic identification methods. In this study, we defined the core genome and accessory genes of C. fetus, which are based on the closed genomes of five C. fetus strains. Phylogenetic analysis of the core genomes of 23 C. fetus strains of the two subspecies showed a division into two clusters. The phylogenetic core genome clusters were not consistent with the phenotypic classifications of the C. fetus subspecies. However, they were consistent with the molecular characteristics of the strains, which were determined by multilocus sequence typing, sap typing, and the presence/absence of insertion sequences and a type I restriction modification system. The similarity of the genome characteristics of three of the phenotypically defined C. fetus subsp. fetus strains to C. fetus subsp. venerealis strains, when considering the core genome and accessory genes, requires a critical evaluation of the clinical relevance of C. fetus subspecies identification by phenotypic assays. Copyright © 2014, American Society for Microbiology. All Rights Reserved.