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Find video protocols related to scientific articles indexed in Pubmed.
Leptospira spp. in rodents and shrews in Germany.
Int J Environ Res Public Health
PUBLISHED: 04-30-2014
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Leptospirosis is an acute, febrile disease occurring in humans and animals worldwide. Leptospira spp. are usually transmitted through direct or indirect contact with the urine of infected reservoir animals. Among wildlife species, rodents act as the most important reservoir for both human and animal infection. To gain a better understanding of the occurrence and distribution of pathogenic leptospires in rodent and shrew populations in Germany, kidney specimens of 2973 animals from 11 of the 16 federal states were examined by PCR. Rodent species captured included five murine species (family Muridae), six vole species (family Cricetidae) and six shrew species (family Soricidae). The most abundantly trapped animals were representatives of the rodent species Apodemus flavicollis, Clethrionomys glareolus and Microtus agrestis. Leptospiral DNA was amplified in 10% of all animals originating from eight of the 11 federal states. The highest carrier rate was found in Microtus spp. (13%), followed by Apodemus spp. (11%) and Clethrionomys spp. (6%). The most common Leptospira genomospecies determined by duplex PCR was L. kirschneri, followed by L. interrogans and L. borgpetersenii; all identified by single locus sequence typing (SLST). Representatives of the shrew species were also carriers of Leptospira spp. In 20% of Crocidura spp. and 6% of the Sorex spp. leptospiral DNA was detected. Here, only the pathogenic genomospecies L. kirschneri was identified.
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A transgenic probiotic secreting a parasite immunomodulator for site-directed treatment of gut inflammation.
Mol. Ther.
PUBLISHED: 04-16-2014
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New treatment strategies for inflammatory bowel disease are needed and parasitic nematode infections or application of helminth components improve clinical and experimental gut inflammation. We genetically modified the probiotic bacterium Escherichia coli Nissle 1917 to secrete the powerful nematode immunomodulator cystatin in the gut. This treatment was tested in a murine colitis model and on post-weaning intestinal inflammation in pigs, an outbred model with a gastrointestinal system similar to humans. Application of the transgenic probiotic significantly decreased intestinal inflammation in murine acute colitis, associated with increased frequencies of Foxp3(+) Tregs, suppressed local interleukin (IL)-6 and IL-17A production, decreased macrophage inflammatory protein-1?/?, monocyte chemoattractant protein -1/3, and regulated upon activation, normal T-cell expressed, and secreted expression and fewer inflammatory macrophages in the colon. High dosages of the transgenic probiotic were well tolerated by post-weaning piglets. Despite being recognized by T cells, secreted cystatin did not lead to changes in cytokine expression or macrophage activation in the colon. However, colon transepithelial resistance and barrier function were significantly improved in pigs receiving the transgenic probotic and post-weaning colon inflammation was reduced. Thus, the anti-inflammatory efficiency of a probiotic can be improved by a nematode-derived immunoregulatory transgene. This treatment regimen should be further investigated as a potential therapeutic option for inflammatory bowel disease.
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F1 and tbilisi are closely related brucellaphages exhibiting some distinct nucleotide variations which determine the host specificity.
Genome Announc
PUBLISHED: 02-01-2014
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We report on the 41,143-bp genome of brucellaphage F1, a podovirus that infects several Brucella species. The F1 genome is almost identical to the genome of brucellaphage Tb. However, some structural proteins of the phages exhibit extensive polymorphisms and might be responsible for their different host ranges.
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Epidemiology of Giardia duodenalis infection in ruminant livestock and children in the Ismailia province of Egypt: insights by genetic characterization.
Parasit Vectors
PUBLISHED: 01-15-2014
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Giardia duodenalis is a common flagellated protozoan parasite that infects the small intestine of a wide range of vertebrate hosts. This study aimed to determine whether tracing of G. duodenalis isolates by current genetic typing tools is possible using an exemplary set of samples from infected cattle, buffalo and children from the Ismailia province, Egypt.
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Comparison between two commercially available serological tests and polymerase chain reaction in the diagnosis of Cryptosporidium in animals and diarrhoeic children.
Parasitol. Res.
PUBLISHED: 07-20-2013
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For the detection of Cryptosporidium species in 804 animals and 165 diarrhoeic children (<10 years) in Egypt, two copro-antigen tests, the RIDASCREEN® Cryptosporidium test [enzyme immunoassay (EIA)] and the RIDA®QUICK Cryptosporidium/Giardia Combi [immuno-chromatographic test (ICT)] as well as polymerase chain reaction (PCR) were used. Prevalence of Cryptosporidium was 15.0, 19.5 and 32.3 % in animals and 2.4, 6.7 and 49.1 % in children using EIA, ICT and PCR, respectively.Using PCR as reference method, animal samples sensitivity (Se) of the EIA was 46.5 % when questionable samples were considered positive, whereas specificity (Sp) was 100 %. Se of the ICT was 60.4 % while Sp was 100 %. Positive predictive values (PPVs) for both EIA and ICT test were 100 %, and negative predictive values (NPVs) for EIA were 79.7 and 84.1 % for ICT. For the children samples, the Se of EIA was 5 %, Sp was 100 %, PPV was 100 % and NPV was 52.2 %, while the Se of ICT was 13.6 %, Sp was 100 %, PPV was 100 % and NPV was 54.6 %.The Kappa score of agreement between PCR and ICT was 67.4 %, 54.1 % between PCR and EIA and 84.4 % between ICT and EIA. Until the second serial dilution of the EIA and ICT test, 9?×?10(3) oocysts/?l of Cryptosporidia was detected, whereas in PCR, they were detected until the sixth serial dilution. Copro-antigen tests were easy to perform and less time-consuming but less sensitive compared to PCR. They obviously are best applicable for screening and epidemiological studies of large numbers of subjects, for batch specimen processing and in isolated or rural areas where reliable tests like PCR are unfeasible. When in children, a single stool sample is used for the diagnosis of clinical cases; better results can be obtained when non-standardized PCR due low specificity is coupled with copro-antigen tests.
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Interlaboratory comparison of intact-cell matrix-assisted laser desorption ionization-time of flight mass spectrometry results for identification and differentiation of Brucella spp.
J. Clin. Microbiol.
PUBLISHED: 07-12-2013
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Classical microbiological diagnosis of human brucellosis is time-consuming, hazardous, and subject to variable interpretation. Intact-cell matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) was evaluated for the routine identification of Brucella spp. Analysis of mass peak patterns allowed accurate identification to the genus level. However, statistical models based on peak intensities were needed for definite species differentiation. Interlaboratory comparison confirmed the reproducibility of the results.
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Enterococcus faecium NCIMB 10415 supplementation affects intestinal immune-associated gene expression in post-weaning piglets.
Vet. Immunol. Immunopathol.
PUBLISHED: 06-03-2013
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In a Salmonella challenge study of weaned piglets supplemented with the probiotic Enterococcus faecium NCIMB 10415 (SF68), we observed a delayed, post-infection proliferative response of purified blood mononuclear cell fractions towards Salmonella antigens. In order to clarify this observation, we examined the patterns of immune-associated gene expression in long-term feeding trials of both pre- and post-weaning piglets. Piglets supplemented with E. faecium NCIMB 10415 showed a post-weaning dysregulation in the expression patterns of both pro- and anti-inflammatory cytokine expression in intestinal tissues and spleen. Piglets of the supplemented group showed significantly reduced levels of IL-8, IL-10 and the co-stimulatory molecule CD86 mRNA expression in ileal Peyers patches. The expression of CTLA4, an inhibitor of T-cell activation/proliferation, showed similar levels of expression in all tissues examined, particularly in ileal Peyers patches post-weaning where IL-8, IL-10 and CD86 transcript levels were significantly reduced relative to control animals. Blood serum cytokine protein levels showed elevated TGF? in pre-weaning piglets which, together with IL-6, may have suppressed IFN? production in the probiotic-fed animals. In a second Salmonella challenge study, post-weaning, E. faecium-fed animals showed significantly elevated levels of IL-8 gene expression in mesenteric lymph nodes, but reduced levels in the spleen. At early times post-infection, the probiotic-fed group showed similar levels of IL-10, CD86 and CTLA4 mRNA expression as the control animals in intestinal Peyers Patches, despite high relative levels of IL-8 expression in mesenteric lymph nodes. The sum of the observations suggests that supplementation of pre-weaning piglets with E. faecium affects intestinal immune-associated gene expression, which is aggravated post-weaning when the animals receive increased levels of the probiotic in feed. We suggest the post-weaning reductions in gene expression may delay the host response to infections, and provide pathogenic bacteria such as Salmonella with a "window of opportunity", leading to the increased bacterial loads and shedding observed in challenge trials. Possible mechanisms explaining these effects of E. faecium NCIMB 10415 are discussed.
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No protective effects of high-dosage dietary zinc oxide on weaned pigs infected with Salmonella enterica serovar typhimurium DT104.
Appl. Environ. Microbiol.
PUBLISHED: 02-22-2013
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Twenty-eight-day-old weaned pigs were fed diets with a low (LZn), medium (MZn), or high (MZn) Zn concentration (50 to 80, 150, or 2,500 mg Zn/kg of diet, respectively) provided as zinc oxide (ZnO)(24 pigs per group). They were infected orally with Salmonella enterica serovar Typhimurium DT104 on day 32. Salmonellae were cultivated from feces (up to 42 days postinfection [dpi]) and organs (2 and 42 dpi). Activation of the adaptive systemic and mucosal immune systems was investigated by recording anti-Salmonella IgG levels and levels of B and T lymphocyte subpopulations in blood and gut-associated lymphatic tissue. Growth performance was recorded as well. Salmonellae were shed at higher levels and for longer periods in the HZn group (P < 0.05), with no differences in the tissues. At 2 dpi, the relative percentages of CD4(+) T helper cells (P < 0.01) and of CD2(+) T and NK cells (P < 0.01) in blood were reduced from the relative cell counts obtained at 0 dpi, irrespective of the Zn group. The lowest percentage of cytotoxic T cells was found 14 dpi in the HZn group relative to the MZn (P < 0.05) and LZn (P < 0.01) groups. Supplementation of the feed with 2,500 mg Zn/kg of diet immediately after weaning could positively affect the immune responses of piglets infected with Salmonella Typhimurium, but for a short period only. After 2 weeks, all positive effects disappeared, and rather negative effects, such as higher shedding of salmonellae, lower T cell frequencies, and worse performance, occurred. Thus, supplementation with ZnO at high levels in the pig industry should be limited to 2 to 3 weeks.
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Distribution of Leptospira serogroups in dogs from Berlin, Germany.
Vector Borne Zoonotic Dis.
PUBLISHED: 02-21-2013
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Leptospirosis is a bacterial zoonosis in which dogs can act as a reservoir for human infection. The annual vaccination of dogs can prevent leptospirosis caused by serovars included in the vaccine. To date, all available vaccines in Germany include only the serovars Icterohaemorrhagiae and Canicola, the most commonly found serovars prior to the introduction of the leptospirosis vaccines. Yet, the involvement of additional serovars in the clinical presentation of leptospirosis in dogs has been described. The objective of this sero-epidemiological study was to examine the different Leptospira serovars currently circulating in a population of dogs suspicious for leptospirosis from Berlin. In 329 dogs presenting at the Small Animal Clinic in Berlin, the predominant serogroup was Australis (24%), followed by Grippotyphosa (20%) and Pomona (9%). A total of 18% of the dogs were diagnosed with clinical leptospirosis; here the most prevalent serogroups were also Australis (28%), Grippotyphosa (18%), and Pomona (14%). The serovar prevalence data presented here confirm that a change of pattern of infecting Leptospira serovars in dogs has taken place in Berlin. This data corresponds to further sero-epidemiological studies from other regions in Germany. To ensure human and canine health, available vaccines should be adapted to include the most important circulating serovars.
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Trichinella detection: identification and statistical evaluation of sources of error in the magnetic stirrer method for pooled sample digestion.
Vet. Parasitol.
PUBLISHED: 02-05-2013
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Proficiency testing (PT) is the use of inter-laboratory comparisons to determine the performance of individual laboratories for specific tests or measurements, and to monitor a laboratorys performance. Participation in proficiency testing provides laboratories with an objective means of assessing and demonstrating the reliability of the data they are producing. To ensure the reliability of Trichinella detection and meat hygiene within the European Union and afford optimal protection to the consumer, PT is conducted under the direction of the European National Reference Laboratories for Trichinella. Evaluation of data from the national PT showed that lab-internal shortcomings are frequent. These shortcomings are specifically related to: (1) improper sample collection and preparation; (2) incorrect transposition and application of the protocol as laid down in Annex I, Chapter I, Nr. 3 (a-g) of the Commission Regulation (EC) No. 2075/2005; (3) insufficient sedimentation times; and (4) improper equipment.(e.g. Prost and Nowakowski, 1990; Rossi and Pozio, 2008; Forbes and Gajadhar, 1999; Rossi and Pozio, 2008). To test the hypothesis that both method based errors as well as internal lab errors can influence the accuracy and precision of the magnetic stirrer method for pooled sample digestion (MSM), we initiated a study to evaluate the analytical uncertainty of the MSM. Results presented here are based on: (i) data from PT in Germany (2008, 2009, and 2010); (ii) within-lab performance conducting high volumes of MSM; (iii) larval recovery experiments; and (iv) statistical evaluation of data resulting from these procedures. Quantitative data from the PT show that on average only 60% of Trichinella larvae were detected. Even laboratories that showed relatively good performance (>80% larva recovery, no false negative or false positive results), frequently reported samples with an unexpectedly low larval count (loss of >2 larvae). In our own laboratory, high numbers of repeated analyses of standards and re-analyses of residual fluids indicated that these outliers could be described by a binomial distribution based on a laboratory-specific Trichinella-detection probability. Results of recovery experiments indicate that only a part of the total larval losses can be attributed to lab-internal shortcomings inasmuch as a significant number of L1 could be isolated from the residual and washing fluids.
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Intraspecies biodiversity of the genetically homologous species Brucella microti.
Appl. Environ. Microbiol.
PUBLISHED: 12-30-2011
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Brucellosis is one of the major bacterial zoonoses worldwide. In the past decade, an increasing number of atypical Brucella strains and species have been described. Brucella microti in particular has attracted attention, because this species not only infects mammalian hosts but also persists in soil. An environmental reservoir may pose a new public health risk, leading to the reemergence of brucellosis. In a polyphasic approach, comprising conventional microbiological techniques and extensive biochemical and molecular techniques, all currently available Brucella microti strains were characterized. While differing in their natural habitats and host preferences, B. microti isolates were found to possess identical 16S rRNA, recA, omp2a, and omp2b gene sequences and identical multilocus sequence analysis (MLSA) profiles at 21 different genomic loci. Only highly variable microsatellite markers of multiple-locus variable-number tandem repeat (VNTR) analysis comprising 16 loci (MLVA-16) showed intraspecies discriminatory power. In contrast, biotyping demonstrated striking differences within the genetically homologous species. The majority of the mammalian isolates agglutinated only with monospecific anti-M serum, whereas soil isolates agglutinated with anti-A, anti-M, and anti-R sera. Bacteria isolated from animal sources were lysed by phages F1, F25, Tb, BK2, Iz, and Wb, whereas soil isolates usually were not. Rough strains of environmental origin were lysed only by phage R/C. B. microti exhibited high metabolic activities similar to those of closely related soil organisms, such as Ochrobactrum spp. Each strain was tested with 93 different substrates and showed an individual metabolic profile. In summary, the adaptation of Brucella microti to a specific habitat or host seems to be a matter of gene regulation rather than a matter of gene configuration.
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The sylvatic Trichinella cycle and its implications for Trichinella control in Germany.
Berl. Munch. Tierarztl. Wochenschr.
PUBLISHED: 12-24-2011
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Trichinellosis is a food-borne, zoonotic disease caused by a parasitic organism. Pork containing muscle larvae represents the most important source of human trichinellosis. In Germany, each slaughtered domestic swine is systematically sampled and examined for Trichinella spp. European Union legislation (EC (No.) 2075/2005) condones the approach of a risk-oriented meat inspection for Trichinella in pigs which is accompanied by monitoring programmes for pig holdings and reservoir animals. Here we discuss the current epidemiological situation of Trichinella in the sylvatic cycle in Germany and the implications for the implementation of risk-based sampling.
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Comparing validation of four ELISA-systems for detection of Salmonella derby- and Salmonella infantis-infected pigs.
Berl. Munch. Tierarztl. Wochenschr.
PUBLISHED: 08-19-2011
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The objective of this study was the comparative evaluation of four indirect Salmonella ELISA tests at study time approved in Germany to detect Salmonella infection in pigs.Three tests are based on a LPS-antigen mix and directed against specific IgG antibodies. The fourth test is based on a purified S. Typhimurium whole-cell lysate antigen and discriminates between Salmonella-specific IgM-, IgA-, and IgG- antibodies. In a longitudinal study, two groups of six weeks old hybrid piglets were orally infected with a porcine S. Infantis or S. Derby strain. Clinical and bacteriological parameters were monitored weekly during an observation period of 130 days after infection and serum samples were investigated in parallel with the respective ELISAs. Apparently, the LPS-based ELISA systems used in this study failed to recognize S. Infantis-infected pigs although those animals shed the pathogen in high amounts throughout the study until day 81 post infection (p. i.). In contrast, the isotype-specific Salmonella Typhimurium whole-cell-lysate based ELISA was capable of detecting Salmonella-infected pigs from day ten p. i. at all tested serotypes and revealed the highest sensitivity in detection of S. Infantis-infected pigs. Furthermore, it became apparent that the often used surveillance cut-off value of 40 OD% is not appropriate for intra-vitam detection of S. Infantis- and S. Derby-infected pigs. In contrast, the cut-off values of the ELISAs given by the suppliers result in considerable higher detection rates.
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Implications of laboratory diagnosis on brucellosis therapy.
Expert Rev Anti Infect Ther
PUBLISHED: 08-04-2011
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Brucellosis is a worldwide zoonosis with a huge economic impact on animal husbandry and public health. The diagnosis of human brucellosis can be protracted because the disease primarily presents as fever of unknown origin with unspecific clinical signs and symptoms. The isolation rate of the fastidious etiologic agent from blood cultures is low, and therefore laboratory diagnosis is mainly based on serologic and molecular testing. However, seronegative brucellosis patients have been described, and antibody titers of diagnostic significance are difficult to define. Whether the molecular detection of Brucella DNA in clinical samples should be followed by long-term antibiotic treatment or not is also a matter of debate. The aim of this article is to review and discuss the implications of laboratory test results in the diagnosis of human brucellosis on disease therapy.
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A potential novel Brucella species isolated from mandibular lymph nodes of red foxes in Austria.
Vet. Microbiol.
PUBLISHED: 04-15-2011
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The wild red fox (Vulpes vulpes) is a known indicator species for natural foci of brucellosis. Here, we describe phenotypic and molecular characteristics of two atypical Brucella strains isolated from two foxes hunted 2008 in Eastern Austria. Both strains agglutinated with monospecific anti-Brucella A serum and were positive in ELISA with monoclonal antibodies directed against various Brucella lipopolysaccharide epitopes. However, negative nitrate reductase- and negative oxidase-reaction were atypical traits. Affiliation to the genus Brucella was confirmed by 16S rRNA gene sequencing and by detection of the Brucella specific insertion element IS711 and gene bcsp31 using real-time PCR. Both fox strains showed identical IS711 Southern blot profiles but were distinct from known brucellae. The number of IS711 copies detected was as high as found in B. ovis or marine mammal Brucella strains. Molecular analyses of the recA and omp2a/b genes suggest that both strains possibly represent a novel Brucella species.
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Comparison of two PCR systems for the rapid detection of Leptospira spp. from kidney tissue.
Curr. Microbiol.
PUBLISHED: 08-16-2010
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In this study we compared two routine PCR systems for the detection of Leptospira spp. and assessed their performance when directly applied to kidney samples from small mammals. Although the kappa value of 0.9 indicated a high level of agreement between the tests, the outer membrane lipoprotein gene lipl32 based PCR was more robust and showed a higher number of positive kidney samples.
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Differential phenotyping of Brucella species using a newly developed semi-automated metabolic system.
BMC Microbiol.
PUBLISHED: 06-28-2010
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A commercial biotyping system (Taxa Profile™, Merlin Diagnostika) testing the metabolization of various substrates by bacteria was used to determine if a set of phenotypic features will allow the identification of members of the genus Brucella and their differentiation into species and biovars.
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Increased prevalence of Trichinella spp., northeastern Germany, 2008.
Emerging Infect. Dis.
PUBLISHED: 05-29-2010
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In 2008, a Trichinella spp. outbreak occurred on a small family-owned pig farm in Mecklenburg-Western Pomerania in northeastern Germany. To obtain epidemiologic information on this outbreak, we determined that after 2005 the prevalence of Trichinella spp. in wild boars has increased in this region of Germany. We discuss the potential role of the raccoon dog in the increase in Trichinella spp. prevalence in the sylvatic cycle in this region. We believe that this increase could pose a threat to pigs kept in back yard conditions, and we provide recommendations to ensure public health safety.
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Outbreak of leptospirosis among triathlon participants in Germany, 2006.
BMC Infect. Dis.
PUBLISHED: 04-10-2010
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In August 2006, a case of leptospirosis occurred in an athlete after a triathlon held around Heidelberg and in the Neckar river. In order to study a possible outbreak and to determine risk factors for infection an epidemiological investigation was performed.
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Survival of Brucella spp. in mineral water, milk and yogurt.
Int. J. Food Microbiol.
PUBLISHED: 03-18-2010
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Knowledge of the number of organisms in a food product at the time of consumption is crucial to assess the risk from a deliberate contamination of food samples with Brucella. To date, very little data on the survival times of Brucella in different food matrices is available. This study was conducted to assess the survival times of Brucella spp. in water, milk and yogurt. These food products were inoculated with bacteria, serial dilutions of the food samples plated and the number of surviving bacteria counted. Under normal storage conditions Brucella survived in UHT milk for 87 days, for 60 days in water and less than a week in yogurt. Also, when milk was inoculated with low bacterial numbers, Brucella multiplied by five log units within three weeks. Further we could not confirm that a high fat content in food has a protective effect on Brucella survival. Brucella survived in 3.5% and 10.0% fat yogurt for four and two days, respectively. These results show that appropriate methods for the rapid detection of this pathogen from food matrices are required.
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Trichinella diagnostics and control: mandatory and best practices for ensuring food safety.
Vet. Parasitol.
PUBLISHED: 12-16-2009
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Because of its role in human disease, there are increasing global requirements for reliable diagnostic and control methods for Trichinella in food animals to ensure meat safety and to facilitate trade. Consequently, there is a need for standardization of methods, programs, and best practices used in the control of Trichinella and trichinellosis. This review article describes the biology and epidemiology of Trichinella, and describes recommended test methods as well as modified and optimized procedures that are used in meat inspection programs. The use of ELISA for monitoring animals for infection in various porcine and equine pre- and post-slaughter programs, including farm or herd certification programs is also discussed. A brief review of the effectiveness of meat processing methods, such as freezing, cooking and preserving is provided. The importance of proper quality assurance and its application in all aspects of a Trichinella diagnostic system is emphasized. It includes the use of international quality standards, test validation and standardization, critical control points, laboratory accreditation, certification of analysts and proficiency testing. Also described, are the roles and locations of international and regional reference laboratories for trichinellosis where expert advice and support on research and diagnostics are available.
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Transmission risk of human trichinellosis.
Vet. Parasitol.
PUBLISHED: 12-16-2009
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Trichinella is a food-borne parasitic zoonoses and human cases are still reported in Europe mainly due to the consumption of pig meat originating from small backyard farms. Infections originating from industrialized pig farming have not been reported for decades in Europe, due to control measures to prevent the transmission of Trichinella from wildlife by indoor housing and good management practices. Therefore, risk-based monitoring programs might replace individual carcass control in industrialized pig farming as described in EU legislation SANCO 2075/2005. Transmission of Trichinella species between wildlife and the risk that may pose to humans via consumption of contaminated pork meat has not been studied quantitatively. One pathway by which human trichinellosis can occur is the rat-pig-human route. To evaluate the transmission risk though this pathway the dose responses of rat, pig, and human were studied. Experimental T. spiralis infection was performed in rats with doses of as few as 10 parasites and the data set was analysed using a newly developed dose response model that describes larvae per gram (LPG). Experimental T. spiralis infection in pig was analysed in a similar way. Furthermore nine published outbreaks of human trichinellosis were analysed to determine the dose response in humans. The risk of human trichinellosis via the rat-pig-human transmission was simulated by the Monte Carlo method. A pair of female and male parasites representing the lowest infection pressure from the environment, led to the probability of human trichinellosis by consumption of 100g of raw pork meat equal to 5% via the studied rat-pig-human pathway. In the absence of rodent control near the farm, a low infection pressure from wildlife presents a relatively high risk of human trichinellosis via consumption of uncooked pork meat.
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Brucella inopinata sp. nov., isolated from a breast implant infection.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 08-06-2009
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A Gram-negative, non-motile, non-spore-forming coccoid bacterium (strain BO1(T)) was isolated recently from a breast implant infection of a 71-year-old female patient with clinical signs of brucellosis. Affiliation of strain BO1(T) to the genus Brucella was confirmed by means of polyamine pattern, polar lipid profile, fatty acid profile, quinone system, DNA-DNA hybridization studies and by insertion sequence 711 (IS711)-specific PCR. Strain BO1(T) harboured four to five copies of the Brucella-specific insertion element IS 711, displaying a unique banding pattern, and exhibited a unique 16S rRNA gene sequence and also grouped separately in multilocus sequence typing analysis. Strain BO1(T) reacted with Brucella M-monospecific antiserum. Incomplete lysis was detected with bacteriophages Tb (Tbilisi), F1 and F25. Biochemical profiling revealed a high degree of enzymic activity and metabolic capabilities. In multilocus VNTR (variable-number tandem-repeat) analysis, strain BO1(T) showed a very distinctive profile and clustered with the other exotic Brucella strains, including strains isolated from marine mammals, and Brucella microti, Brucella suis biovar 5 and Brucella neotomae. Comparative omp2a and omp2b gene sequence analysis revealed the most divergent omp2 sequences identified to date for a Brucella strain. The recA gene sequence of strain BO1(T) differed in seven nucleotides from the Brucella recA consensus sequence. Using the Brucella species-specific multiplex PCR assay, strain BO1(T) displayed a unique banding pattern not observed in other Brucella species. From the phenotypic and molecular analysis it became evident that strain BO1( T) was clearly different from all other Brucella species, and therefore represents a novel species within the genus Brucella. Because of its unexpected isolation, the name Brucella inopinata with the type strain BO1(T) (=BCCN 09-01(T)=CPAM 6436(T)) is proposed.
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Molecular epidemiology of Brucella genotypes in patients at a major hospital in central Peru.
J. Clin. Microbiol.
PUBLISHED: 08-05-2009
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The multiple-locus variable-number repeat analysis of 90 human Brucella melitensis isolates from a large urban area in central Peru revealed variations at 4 (Bruce07, Bruce09, Bruce18, and Bruce42) out of 16 loci investigated, of which 1 (Bruce42) also is used for species identification. Ten genotypes were identified, separated by the number of Bruce42 repeats into two groups that may have distinct phenotypic characteristics. Whereas genotypes with five or six Bruce42 repeats were cultured mainly from adult patients, genotypes with three Bruce42 repeats were isolated from children and young adolescents as well as from adults. In addition, the isolates with three Bruce42 repeats were obtained more often from patients with splenomegaly (P = 0.02) or hepatomegaly (P = 0.006). An annual variation in the diversity of genotypes was observed, possibly reflecting changes in sources of fresh dairy products, supply routes to city shops and markets, and the movement of infected dairy goat herds.
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MLVA genotyping of human Brucella isolates from Peru.
Trans. R. Soc. Trop. Med. Hyg.
PUBLISHED: 07-28-2009
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Recent human Brucella melitensis isolates from Peru were genotyped by multiple locus variable number repeat analysis. All 24 isolates originated from hospitalized patients living in the central part of Peru and consisted of six genomic groups comprising two to four isolates and nine unique genotypes. The isolates were most closely related to the two previously genotyped isolates from Mexico, with a maximum distance of 2 to 4. The Peruvian strains were clearly distinct from the East and West Mediterranean groups of B. melitensis genotypes, suggesting that they may constitute a unique Latin American cluster.
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Advancement of a multiplex PCR for the differentiation of all currently described Brucella species.
J. Microbiol. Methods
PUBLISHED: 07-16-2009
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To facilitate routine laboratories in the effective diagnosis of brucellosis, we report a robust and rapid multiplex PCR assay, which allows for the differentiation of all nine currently recognised Brucella species. This includes the recently described species B. microti, B. inopinata, B. ceti and B. pinnipedialis.
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Enterobacteriaceae populations during experimental Salmonella infection in pigs.
Vet. Microbiol.
PUBLISHED: 05-26-2009
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Salmonella infection might affect other intestinal Enterobacteriaceae populations and possible correlations between single Enterobacteriaceae populations would help to predict subclinical Salmonella infections in pigs. In one experimental setup, weaned piglets (n=40) were infected with Salmonella and sacrificed at 3h, 24h, 72 h or 28 days post-infection (p.i.). Dilutions of intestinal contents and mucosal tissues were plated on agar plates for determinations of Enterobacteriaceae. In another experimental setup, weaned piglets (n=12) were infected with Salmonella and probed over a period of 28 days p.i., and dilutions of rectal contents were also tested for Enterobacteriaceae populations. The occurrence of single Enterobacteriaceae populations was correlated with the occurrence of other tested Enterobacteriaceae populations as well as with clinical parameters of the piglets. Salmonella (infection strain), Escherichia coli (hemolytic and non-hemolytic) and another six non-E. coli/non-Salmonella Enterobacteriaceae (NENSE) genera with eight species were identified. In general, the absolute numbers of E. coli, Salmonella and NENSE populations decreased with increasing age of the animals. In the jejunum, the numbers of NENSE, E. coli and Salmonella were all highly positively correlated with each other. The occurrence of hemolytic E. coli had no obvious effects on the occurrence of other Enterobacteriaceae. Furthermore, only few associations of Enterobacteriaceae populations with clinical parameters were observed. In conclusion, we did not observe evidences for either a competition between or benefits for specific Enterobacteriaceae populations during Salmonella infection indicating that changes in the composition of the intestinal Enterobacteriaceae microflora are not useful indicators of subclinical Salmonella infections.
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Biological risks associated with consumption of reptile products.
Int. J. Food Microbiol.
PUBLISHED: 03-27-2009
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The consumption of a wide variety of species of reptiles caught from the wild has been an important source of protein for humans world-wide for millennia. Terrapins, snakes, lizards, crocodiles and iguanas are now farmed and the consumption and trade of their meat and other edible products have recently increased in some areas of the world. Biological risks associated with the consumption of products from both farmed and wild reptile meat and eggs include infections caused by bacteria (Salmonella spp., Vibrio spp.), parasites (Spirometra, Trichinella, Gnathostoma, pentastomids), as well as intoxications by biotoxins. For crocodiles, Salmonella spp. constitute a significant public health risk due to the high intestinal carrier rate which is reflected in an equally high contamination rate in their fresh and frozen meat. There is a lack of information about the presence of Salmonella spp. in meat from other edible reptilians, though captive reptiles used as pets (lizards or turtles) are frequently carriers of these bacteria in Europe. Parasitic protozoa in reptiles represent a negligible risk for public health compared to parasitic metazoans, of which trichinellosis, pentastomiasis, gnathostomiasis and sparganosis can be acquired through consumption of contaminated crocodile, monitor lizard, turtle and snake meat, respectively. Other reptiles, although found to harbour the above parasites, have not been implicated with their transmission to humans. Freezing treatment inactivates Spirometra and Trichinella in crocodile meat, while the effectiveness of freezing of other reptilian meat is unknown. Biotoxins that accumulate in the flesh of sea turtles may cause chelonitoxism, a type of food poisoning with a high mortality rate in humans. Infections by fungi, including yeasts, and viruses widely occur in reptiles but have not been linked to a human health risk through the contamination of their meat. Currently there are no indications that natural transmissible spongiform encephalopathies (TSEs) occur in reptilians. The feeding of farmed reptiles with non-processed and recycled animal products is likely to increase the occurrence of biological hazards in reptile meat. Application of GHP, GMP and HACCP procedures, respectively at farm and slaughterhouse level, is crucial for controlling the hazards.
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Influence of a probiotic strain of Enterococcus faecium on Salmonella enterica serovar Typhimurium DT104 infection in a porcine animal infection model.
Appl. Environ. Microbiol.
PUBLISHED: 03-06-2009
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The beneficial effects of probiotic Enterococcus spp. in different hosts, such as mice and humans, have previously been reported in several studies. However, studies of large domestic animals, as well as challenge studies with pathogenic microorganisms, are very rare. Here, we investigated the influence of oral treatment of pigs with the probiotic bacterium Enterococcus faecium NCIMB 10415 on Salmonella enterica serovar Typhimurium DT104 infections in weaning piglets. Clinical symptoms, fecal excretion, the organ distribution of Salmonella, and the humoral immune response (immunoglobulin G [IgG], IgM, and IgA levels) in serum were examined. A pool of 89 piglets was randomly divided into probiotic and control groups. The probiotic group received a feed supplement containing E. faecium starting on day 14 postpartum prior to challenge with Salmonella serovar Typhimurium DT104 at 28 days postpartum. After challenge with Salmonella serovar Typhimurium DT104, piglets in both groups showed no severe clinical signs of salmonellosis. However, fecal excretion and colonization of Salmonella in organs were significantly greater in piglets fed E. faecium. Likewise, the humoral immune response against Salmonella (serum IgM and IgA levels) was significantly greater in the probiotic group animals than in control animals. The results of this study suggest that E. faecium NCIMB 10415 treatment enhanced the course of infection in weaning piglets challenged with Salmonella serovar Typhimurium DT104. However, the probiotic treatment also appeared to result in greater production of specific antibodies against Salmonella serovar Typhimurium DT104.
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Identification of Encephalitozoon cuniculi genotype III and two novel genotypes of Enterocytozoon bieneusi in swine.
Parasitol. Int.
PUBLISHED: 02-19-2009
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Samples of intestinal content from thirty fattened pigs of six farms slaughtered at an abattoir in North-Western Germany, and faecal samples of four pigs kept as laboratory animals at the Federal Institute for Risk Assessment (BfR, Berlin, Germany) were investigated for the occurrence of microsporidia by light microscopy, PCR and sequencing. A modified Webers trichrome staining and the immunohistochemistry (the Avidin-Biotin-Peroxidase-Complex technique with a polyclonal anti-Encephalitozoon cuniculi-serum and monoclonal antibodies against Encephalitozoon intestinalis and Enterocytozoon bieneusi) was used as a screening method for the light microscopical detection of these pathogenic eukaryotes. By this light microscopically methods microsporidia suspected organisms were found in all samples (100%). By the use of PCR, microsporidia were identified in fourteen samples (41.2%). The prevalence of microsporidia infections among the farms diversifies from 0 to 80% as considered by PCR. E. bieneusi was the most prevalent species and was identified in twelve fattened pigs (40%) from five of the six tested farms (83.3%) and in two of the four laboratory animals (50%). Three of the E. bieneusi species belonged to the genotype O, one to the genotype E, and one to the genotype F. Two isolates were identified as novel genotypes and two samples showed a mixed infection of different genotypes. In three faecal samples of the pigs from two farms E. cuniculi genotype III was identified. One sample contained both microsporidia species. To our knowledge, this is the first time that the genotype III of E. cuniculi was identified in swine.
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Resurgence of field fever in a temperate country: an epidemic of leptospirosis among seasonal strawberry harvesters in Germany in 2007.
Clin. Infect. Dis.
PUBLISHED: 02-06-2009
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Although leptospirosis is a reemerging zoonosis of global importance, outbreaks related to agricultural exposures are primarily situated in tropical countries. In July 2007, a suspected leptospirosis outbreak was recognized among strawberry harvesters from Eastern Europe who were working in Germany. An investigation was initiated to identify the outbreak source and the risk factors for infection.
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Epidemiology, diagnosis, treatment, and control of trichinellosis.
Clin. Microbiol. Rev.
PUBLISHED: 01-13-2009
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Throughout much of the world, Trichinella spp. are found to be the causative agents of human trichinellosis, a disease that not only is a public health hazard by affecting human patients but also represents an economic problem in porcine animal production and food safety. Due to the predominantly zoonotic importance of infection, the main efforts in many countries have focused on the control of Trichinella or the elimination of Trichinella from the food chain. The most important source of human infection worldwide is the domestic pig, but, e.g., in Europe, meats of horses and wild boars have played a significant role during outbreaks within the past 3 decades. Infection of humans occurs with the ingestion of Trichinella larvae that are encysted in muscle tissue of domestic or wild animal meat. Early clinical diagnosis of trichinellosis is rather difficult because pathognomonic signs or symptoms are lacking. Subsequent chronic forms of the disease are not easy to diagnose, irrespective of parameters including clinical findings, laboratory findings (nonspecific laboratory parameters such as eosinophilia, muscle enzymes, and serology), and epidemiological investigations. New regulations laying down rules for official controls for Trichinella in meat in order to improve food safety for consumers have recently been released in Europe. The evidence that the disease can be monitored and to some extent controlled with a rigorous reporting and testing system in place should be motivation to expand appropriate programs worldwide.
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Molecular epidemiology of Cryptosporidium in livestock animals and humans in the Ismailia province of Egypt.
Vet. Parasitol.
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The zoonotic potential of Cryptosporidium was studied in one of the most densely populated provinces of Egypt regarding livestock and people. In a representative survey, faecal samples from cattle, buffalo and stool samples from diarrhoeic children (<10 years) were investigated. Parameters assumed to be related to cryptosporidiosis were recorded for animals and children. Animal samples (804) were examined by the Copro-antigen RIDA(®)QUICK test, followed by PCRs targeting the 18S rDNA and gp60 genes for antigen-positive and 10% randomly selected negative samples. All 165 human samples were tested by both methods. The overall estimated prevalence of Cryptosporidium in ruminants was 32.2%, without significant difference between animal species. PCR identified 65.7% Cryptosporidium parvum, 11.8% Cryptosporidium ryanae, 4.1% Cryptosporidium bovis, and combinations of C. parvum plus C. ryanae (11.2%), C. parvum plus C. bovis (5.3%) and of C. parvum plus Cryptosporidium andersoni (1.8%), also without significant differences in species occurrence between cattle and buffalos. The human Cryptosporidium spp. prevalence was 49.1%, of which 60.5% were Cryptosporidium hominis, 38.2% C. parvum and 1.2% C. parvum plus C. bovis. Analysis of gp60 variants allocated C. parvum found in animals to the zoonotic subtype family IIa (18.9%, subtype IIaA15G1R1 only) and to IId (81.1%, mostly IIdA20G1). In humans 50% were classified as subtype family IIa (IIaA15G1R1 and IIaA15G2R1) and 50% were IIdA20G1. C. andersoni occurred only in cattle older than 1 year. In contrast, mono-infections with one of the three single Cryptosporidium species and the three combinations with C. parvum were more prevalent in cattle and buffaloes younger than 1 year, particularly in those younger than 3 months, and were predominantly subtype family IId. In human samples no Cryptosporidium were identified in children younger than 7 months. Neither place of residence nor the source of drinking-water had measurable effects on prevalence. Remarkably, however, all children with C. parvum subtype family IIa and 86% with subtype family IId had contact to animals. High prevalence and identical genotypes of C. parvum in animals and humans indicate zoonotic transmission due to contact with animals, involving IIdA20G1 as the most frequent subtype.
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[Surveillance systems for status monitoring of Trichinella-free declared pig farms: concepts and their confidence for freedom from disease].
Berl. Munch. Tierarztl. Wochenschr.
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Trichinella surveillance data in Germany show for indoor housed pigs hardly any cases. Nevertheless, obligatory testing is in place for each slaughtered pig. According to EU legislation systematic Trichinella testing can be replaced by a risk-based surveillance system if the risk of Trichinella infection in fattening pigs is negligible. The probability to detect a positive herd (herd sensitivity) was taken as an indicator for the effectiveness of the surveillance. Four different diagnostic methods: a) digestion method, b) E/S-ELISA, c) Western Blot, and d) ELISA sequentially combined with Western Blot, were compared regarding herd sensitivity and specificity for different herd and sample sizes and different levels of prevalence. In a further step three potential surveillance systems were compared with regard to their suitability for herd classification: (i) classical Trichinella examination by artificial digestion method, (ii) ELISA screening followed by classical Trichinella examination and (iii) ELISA screening followed by Western Blot. Results show that: 1) testing by the artificial digestion method (i) provides only low sensitivity of detection for positive herds at present levels of prevalence despite perfect specificity. 2) The ELISA alone provides a high sensitivity of detection even at low sample sizes but at the cost of a very low herd specificity, converging towards zero at increasing sample sizes. In surveillance system (ii), a large number of farms would still need to be tested with the classical digestion method, as they would be misclassified as positive by the ELISA. 3) The Western Blot as well as ELISA screening followed by Western Blot offer a high probability of correct herd classification. The latter diagnostic system appears to be the most suitable for a risk based surveillance (iii) and provides--despite reduced sample sizes--a higher probability for a correct herd classification than the traditional Trichinella examination.
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Experimental infection of weaned piglets with Campylobacter coli--excretion and translocation in a pig colonisation trial.
Vet. Microbiol.
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Campylobacter (C.) is one of the most common food-borne pathogen causing bacterial enteric infections in humans. Consumption of meat and meat products that have been contaminated with Campylobacter are the major source of infection. Pigs are a natural reservoir of Campylobacter spp. with C. coli as the dominant species. Even though some studies focussed on transmission of C. coli in pig herds and the excretion in faeces, little is known about the colonisation and excretion dynamics of C. coli in a complex gut microbiota present in weaned piglets and the translocation to different tissues. Therefore, an experimental trial was conducted to evaluate the colonisation and translocation ability of the porcine strain C. coli 5981 in weaned pigs. Thus, ten 35 days old piglets were intragastrically inoculated with strain C. coli 5981 (7 × 10(7)CFU/animal) encoding resistances against erythromycin and neomycin. Faecal samples were taken and C. coli levels were enumerated over 28 days. All piglets were naturally colonised with C. coli before experimental inoculation, and excretion levels ranged from 10(4) to 10(7)CFU/g faeces. However, no strain showed resistances against the additional antimicrobials used. Excretion of C. coli 5981 was seen for all piglets seven days after inoculation and highest counts were detectable ten days after inoculation with 10(6)CFU/g faeces. Post-mortem, translocation and subsequent invasion of luminal C. coli was observed for gut tissues of the small intestine and for the gut associated lymphatic tissues, such as jejunal mesenteric lymph nodes and tonsils as well as for spleen and gall bladder. In conclusion, this pig colonisation trial offers the opportunity to study C. coli colonisation in weaned piglets using the porcine strain C. coli 5981 without the need for gnotobiotic or specific pathogen-free animals.
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No beneficial effects evident for Enterococcus faecium NCIMB 10415 in weaned pigs infected with Salmonella enterica serovar Typhimurium DT104.
Appl. Environ. Microbiol.
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Salmonella enterica serovar Typhimurium DT 104 is the major pathogen for salmonellosis outbreaks in Europe. We tested if the probiotic bacterium Enterococcus faecium NCIMB 10415 can prevent or alleviate salmonellosis. Therefore, piglets of the German Landrace breed that were treated with E. faecium (n = 16) as a feed additive and untreated controls (n = 16) were challenged with S. Typhimurium 10 days after weaning. The presence of salmonellae in feces and selected organs, as well as the immune response, were investigated. Piglets treated with E. faecium gained less weight than control piglets (P = 0.05). The feeding of E. faecium had no effect on the fecal shedding of salmonellae and resulted in a higher abundance of the pathogen in tonsils of all challenged animals. The specific (anti-Salmonella IgG) and nonspecific (haptoglobin) humoral immune responses as well as the cellular immune response (T helper cells, cytotoxic T cells, regulatory T cells, ?? T cells, and B cells) in the lymph nodes, Peyers patches of different segments of the intestine (jejunal and ileocecal), the ileal papilla, and in the blood were affected in the course of time after infection (P < 0.05) but not by the E. faecium treatment. These results led to the conclusion that E. faecium may not have beneficial effects on the performance of weaned piglets in the case of S. Typhimurium infection. Therefore, we suggest a critical discussion and reconsideration of E. faecium NCIMB 10415 administration as a probiotic for pigs.
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Cross-border molecular tracing of brucellosis in Europe.
Comp. Immunol. Microbiol. Infect. Dis.
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To assess the general impact of endemic countries on the re-emergence of brucellosis in non-endemic regions of the European Union, the genetic fingerprints of Brucella melitensis strains imported to Germany were compared to ovine strains from Turkey in a molecular epidemiological study. Genotyping of 66 Brucella strains (based on Multiple Locus of Variable number of tandem repeats Analysis) isolated from German travellers and Turkish immigrants living in Germany revealed epidemiological concordance with 20 sheep isolates originating from Eastern Anatolia, Turkey. In summary, cross-border molecular tracing confirmed brucellosis being a zoonosis of concern for European public health.
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