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See detailClassification of sporadic Creutzfeldt-Jakob disease based on clinical and neuropathological characteristics
Abrahantes, J. C.; Aerts, M.; van Everbroeck, B. et al

in European Journal of Epidemiology (2007), 22(7), 457-465

Creutzfeldt-Jakob disease (CJD) is a rare and fatal neurodegenerative disease of unknown cause. Patients are usually aged between 50 and 75 and typical clinical features include rapidly progressive ... [more ▼]

Creutzfeldt-Jakob disease (CJD) is a rare and fatal neurodegenerative disease of unknown cause. Patients are usually aged between 50 and 75 and typical clinical features include rapidly progressive dementia associated with myoclonus and a characteristic electroencephalographic pattern. Neuropathological examination reveals cortical spongiform change, hence the term 'spongiform encephalopathy'. Several statistical techniques were applied to classify patients with sporadic CJD (sCJD), based on clinical and neuropathological investigation. We focus on the classification of neuropathologically confirmed sCJD patients. In order to obtain a classification rule that correctly classifies this type of patients and at the same time controls the overall error rate, we apply several classification techniques, which in general, produce comparable results. The boosting method produces the best results and the variable 14-3-3 protein in cerebrospinal fluid plays the most important role in the prediction of neuropathologically confirmed sCJD. [less ▲]

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See detailSanitary control in bovine embryo transfer - How far should we go? A review
Van Soom, A.; Imberechts, H.; Delahaut, P. et al

in Veterinary Quarterly (The) (2007), 29(1), 2-17

Embryo transfer is a globally executed technique which, when properly done, has both economic and sanitary advantages. International guidelines are available to prevent infection of the embryo with ... [more ▼]

Embryo transfer is a globally executed technique which, when properly done, has both economic and sanitary advantages. International guidelines are available to prevent infection of the embryo with pathogens, both originating from the donor animals as from the environment. This manuscript describes the bacteria, viruses, protozoa, fungi and prions that are of major concern in the context of embryo transfer in cattle. In addition, the actual scientific knowledge on these pathogens is evaluated in terms of the current international and national guidelines and legislation. [less ▲]

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See detailActualisation et validation interne d’un outil d’aide à la décision clinique de l’encéphalopathie spongiforme bovine en Belgique
Plouvier, Bénédicte ULg; Berkvens, D.; Mennens, K. et al

in Epidémiologie et Santé Animale (2006), 50

The use of regression and classification trees is a usual decision support tool for diseases with low prevalence as well for diseases which diagnosis test not exist actually (emerging diseases). These ... [more ▼]

The use of regression and classification trees is a usual decision support tool for diseases with low prevalence as well for diseases which diagnosis test not exist actually (emerging diseases). These trees make it possible to classify observations (clinical and other) on the basis of a set of predictive variables (categorical or continuous). New data concerning the clinical suspicions of the bovine spongiform encephalopathy were collected in Belgium from November, 2002 until January, 2005. These data make it possible to update and estimate of previous performance characteristics of regression and classification trees. Several modifications of regression and classification tress are proposed and discussed in order to improve epidemiological passive network in Belgium. [less ▲]

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See detailFirst chronic wasting disease surveillance of roe deer (Capreolus capreolus) in North part of Belgium
De Bosschere, H.; Saegerman, Claude ULg; Neukermans, A. et al

in Veterinary Quarterly (The) (2006), 28

Cases of chronic wasting disease (CWD) in wild cervids have yet not been reported in Europe, whereas the disease is considered enzootic in free-ranging mule deer, Rocky mountain elk and white-tailed deer ... [more ▼]

Cases of chronic wasting disease (CWD) in wild cervids have yet not been reported in Europe, whereas the disease is considered enzootic in free-ranging mule deer, Rocky mountain elk and white-tailed deer in the area of Colorado, Wyoming, and Nebraska. New foci of CWD continue to be detected in other parts of the United States. However, no large-scale active epidemiosurveillance of European wild cervids is yet installed in Europe. In accordance with the opinion of the European Scientific Steering Committee, a preliminary (active) surveillance scheme was installed, in order to improve the knowledge of the CWD status of wild cervids (roe deer) in the Northern part of Belgium. Spleen samples (n=206) and brain samples (n=222) of roe deer collected in the Northern part of Belgium, were examined for CWD using the antigen-capture enzyme-linked immunoassay (EIA) of IDEXX. Afterwards, the EIA was systematically confirmed by immunohistochemistry using three antibodies, namely R524, 2G11 and 12F10. There were no indications on the occurrence of TSE in any of the samples. A Bayesian framework was used for the estimation of the true prevalence of CWD in the Northern part of Belgium that was estimated to have a median value of zero with a 95th percentile value of 0.0049 and 0.0045 for spleen and brain samples respectively. [less ▲]

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See detailPopulation-level retrospective study of neurologically expressed disorders in ruminants before the onset of bovine spongiform encephalopathy (BSE) in Belgium, a BSE risk III country.
Saegerman, Claude ULg; Berkvens, D.; Claes, L. et al

in Journal of Clinical Microbiology (2005), 43(2), 862-9

A retrospective epidemiological study (n = 7,875) of neurologically expressed disorders (NED) in ruminants before the onset of the bovine spongiform encephalopathy epidemic (years studied, 1980 to 1997 ... [more ▼]

A retrospective epidemiological study (n = 7,875) of neurologically expressed disorders (NED) in ruminants before the onset of the bovine spongiform encephalopathy epidemic (years studied, 1980 to 1997) was carried out in Belgium. The archives of all veterinary laboratories and rabies and transmissible spongiform encephalopathy (TSE) epidemiosurveillance networks were consulted. For all species, a significantly higher number of NED with virological causes (rabies) was reported south of the Sambre-Meuse Valley. During the period 1992 to 1997, for which the data were complete, (i) the predicted annual incidence of NED varied significantly as a function of species and area (higher numbers in areas where rabies was present) but was always above 100 cases per million, and (ii) the mean incidence of suspected TSE cases and, among them, those investigated by histopathological examination varied significantly as a function of species and area. The positive predictive value of a presumptive clinical diagnosis of NED ranged from 0.13 (game) to 0.63 (sheep). Knowledge of the positive predictive value permits the definition of a reference point before certain actions (e.g., awareness and training campaigns) are undertaken. It also shows the usefulness of a systematic necropsy or complementary laboratory tests to establish an etiological diagnosis. TSE analysis of a small, targeted historical sampling (n = 48) permitted the confirmation of one case and uncovered another case of scrapie. The results of the present study help to develop and maintain the quality of the worldwide clinical epidemiological networks for TSE, especially in countries that in the past imported live animals, animal products, and feedstuffs from countries with TSE cases. [less ▲]

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See detailEstimation de la prévalence réelle de l'encéphalopathie spongiforme bovine en Belgique en 2002 et 2003
Penders, Julie; Praet, Nicolas; Berckvens, D. et al

in Epidémiologie et Santé Animale (2005), 47

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See detailDecision support tools for clinical diagnosis of disease in cows with suspected bovine spongiform encephalopathy.
Saegerman, Claude ULg; Speybroeck, N.; Roels, S. et al

in Journal of Clinical Microbiology (2004), 42(1), 172-8

Reporting of clinically suspected cattle is currently the most common method for detecting cases of bovine spongiform encephalopathy (BSE). Improvement of clinical diagnosis and decision-making remains ... [more ▼]

Reporting of clinically suspected cattle is currently the most common method for detecting cases of bovine spongiform encephalopathy (BSE). Improvement of clinical diagnosis and decision-making remains crucial. A comparison of clinical patterns, consisting of 25 signs, was made between all 30 BSE cases, confirmed in Belgium before October 2002, and 272 suspected cases that were subsequently determined to be histologically, immunohistochemically, and scrapie-associated-fiber negative. Seasonality in reporting suspected cases was observed, with more cases being reported during wintertime when animals were kept indoors. The median duration of illness was 30 days. The 10 most relevant signs of BSE were kicking in the milking parlor, hypersensitivity to touch and/or sound, head shyness, panic-stricken response, reluctance to enter in the milking parlor, abnormal ear movement or carriage, increased alertness behavior, reduced milk yield, teeth grinding, and temperament change. Ataxia did not appear to be a specific sign of BSE. A classification and regression tree was constructed by using the following four features: age of the animal, year of birth, number of relevant BSE signs noted, and number of clinical signs, typical for listeriosis, noted. The model had a sensitivity of 100% and a specificity of 85%. This approach allows the use of an interactive decision-support tool, based entirely on odds ratios, a statistic independent of disease prevalence. [less ▲]

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See detailPutative roles of the CNF2 and CDTIII toxins in experimental infections with necrotoxigenic Escherichia coli type 2 (NTEC2) strains in calves
Van Bost, S.; Roels, S.; Oswald, E. et al

in Microbes & Infection (2003), 5(13), 1189-1193

Newborn colostrum-restricted calves were orally inoculated with an Escherichia coli strain, identified originally as non-pathogenic, and into which the plasmid pVir was conjugally transferred. This ... [more ▼]

Newborn colostrum-restricted calves were orally inoculated with an Escherichia coli strain, identified originally as non-pathogenic, and into which the plasmid pVir was conjugally transferred. This resulted in diarrhea, intestinal lesions and extra-intestinal invasion, suggesting that factors affecting these pathogenic properties are located on pVir. In order to analyze the respective roles of the toxins CNF2 and CDTIII in the pathogenesis, colostrum-restricted calves were inoculated with isogenic mutants in the cnf2 and the cdt-III genes. The loss of cnf2 is associated with a reduction in the pathogenicity, since diarrhea does not occur in calves challenged, in spite of successful colonization of the intestine. Nevertheless, the mutant strain remains able to invade the bloodstream and to localize in the internal organs. Conversely, the calves inoculated with mutant in the cdt-III gene evolved in the same way as wild-type strain-inoculated calves with regard to clinical signs and macroscopic or microscopic lesions. (C) 2003 Editions scientifiques et medicales Elsevier SAS. All rights reserved. [less ▲]

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See detailDifferential diagnosis of neurologically expressed disorders in Western European cattle
Saegerman, Claude ULg; Claes, L.; Dewaele, Albert et al

in Revue Scientifique et Technique (International Office of Epizootics) (2003), 22(1), 83-102

A classification of neurological or neurologically expressed disorders that occur in Western European cattle aged 12 month and over has been established on the basis of aetiology, frequency and conditions ... [more ▼]

A classification of neurological or neurologically expressed disorders that occur in Western European cattle aged 12 month and over has been established on the basis of aetiology, frequency and conditions of appearance, age and type of animals concerned and the main clinical signs observed. Neurologically expressed disorders have been classified according to different groups of causes: biological, non-biological and non-specific or unknown. Differential diagnosis of neurologically expressed disorders is an essential element in the clinical epidemiological surveillance of bovine spongiform encephalopathy. A growing number of aetiologies are described in the scientific literature. The identification and centralised management of neurological disorders will make it possible, one the one hand, to take account of the inherent variability in the clinical forms encountered and in the diagnostic approaches of the observers and, on the other hand, to identify new risk factors in order to control them. [less ▲]

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See detailDiagnostic différentiel des troubles à expression nerveuse dans l’espèce bovine en Europe occidentale
Saegerman, Claude ULg; Claes, L.; Dewaele, A. et al

in Revue Scientifique et Technique (International Office of Epizootics) (2003), 22(1), 61-82

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See detailAmélioration de la détection d’une maladie émergente : exemple de l’ encépahlopathie spongiforme bovine
Saegerman, Claude ULg; Berkvens, D.; Speybroeck, N. et al

in Epidémiologie et Santé Animale (2003), 44

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See detailMycobacterium bovis meningitis in a cow with clinical signs of BSE.
Roels, S.; Walravens, K.; Saegerman, Claude ULg et al

in Veterinary Record : Journal of the British Veterinary Association (2003), 152(26), 807-8

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See detailNecrotoxigenic Escherichia Coli Type-2 Invade and Cause Diarrhoea During Experimental Infection in Colostrum-Restricted Newborn Calves
Van Bost, Sigrid; Roels, S.; Mainil, Jacques ULg

in Veterinary Microbiology (2001), 81(4), 315-29

There exists experimental evidence that necrotoxigenic Escherichia coli (NTEC) strains producing the cytotoxic necrotising factor 1 cause intestinal and extra-intestinal disease in piglets. On the other ... [more ▼]

There exists experimental evidence that necrotoxigenic Escherichia coli (NTEC) strains producing the cytotoxic necrotising factor 1 cause intestinal and extra-intestinal disease in piglets. On the other hand, no experimental model has been developed with NTEC strains producing the cytotoxic necrotising factor 2. In all, 14 colostrum-restricted calves were orally challenged with two strains isolated from the faeces of a diarrheic calf (B20a) or from the heart blood of a septicaemic calf (1404). All calves had diarrhoea which lasted until euthanasia in eight of them. In those calves, diarrhoea was correlated with the faecal excretion of the challenge strains. At necropsy, vascular congestion of the intestinal mucosa, hypertrophy of the mesenteric lymph nodes (MLN) and some congestion of the lungs were observed. Bacteriology confirmed the colonisation of the intestine by the challenge strains which were also recovered from the heart blood, the lungs and/or the liver. Histological sections confirmed enterocolitis, lymphadenitis and limited bronchopneumonia. In the intestinal tissue sections, bacteria testing positive in an in situ DNA hybridisation assay with a CNF2 probe were observed. Those results were confirmed by immunohistochemistry with a polyclonal anti-O78 and a monoclonal anti-F17b antisera. Three of the five control calves receiving either saline or a CNF(-), F17a strain (25KH09) had no clinical signs or lesions. The other two presented a profuse liquid diarrhoea but those calves were positive for the presence of K99(+) E. coli. In this model, both NTEC2 strains were thus, able to colonise the intestine, to cause long-lasting diarrhoea and to invade the blood stream with localisation in various internal organs in colostrum-restricted conventional newborn calves. [less ▲]

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See detailLe diagnostic immunologique rapide des encéphalopathies spongiformes transmissibles
Pastoret, Paul-Pierre ULg; Gouffaux, M.; Saegerman, Claude ULg et al

in Annales de Médecine Vétérinaire (2001), 145

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See detailEpdémiosurveillance de l'encéphalopathie spongiforme bovine en Belgique : bilan de l'année 1999
Saegerman, Claude ULg; Dechamps, P.; Roels, S. et al

in Annales de Médecine Vétérinaire (2001), 145

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See detailClinical Signs, Reproduction of Attaching/Effacing Lesions, and Enterocyte Invasion after Oral Inoculation of an O118 Enterohaemorrhagic Escherichia Coli in Neonatal Calves
Stordeur, P.; China, B.; Charlier, G. et al

in Microbes & Infection (2000), 2(1), 17-24

Attaching and effacing (AE) lesions are produced among others by enteropathogenic Escherichia coli and enterohaemorrhagic E. coli (EHEC), which differs from the former by the production of cytotoxins ... [more ▼]

Attaching and effacing (AE) lesions are produced among others by enteropathogenic Escherichia coli and enterohaemorrhagic E. coli (EHEC), which differs from the former by the production of cytotoxins active on various cell cultures, the verocytotoxins, or shigacytotoxins. EHEC are associated with diarrhoea and dysentery in humans and in ruminants, mainly calves from two to eight weeks of age. Clinical signs and/or lesions have been reproduced experimentally with EHEC strains belonging to serotypes O5:K4/Nm, O26:K-:H11, O111:Nm, and O157:H7 which are isolated from cattle and/or humans. The purpose of this work was to develop an experimental model of infection in newborn calves with a bovine EHEC strain isolated from a calf which of died of diarrhoea, and belonging to the O118:H16 serotype, which is also common to both cattle and humans. The bovine O118:H16 EHEC strain was able to colonize the gut of three newborn calves, and to induce diarrhoea twenty-four hours after challenge and to produce AE lesions in the small and/or large intestines. AE lesions were detected microscopically and ultrastructurally in the small intestine of one calf and in the whole intestinal track of two calves. Internalization of bacteria and also of pedestal-bacteria complex inside of the enterocyte was observed in two of the three calves. The significance of this stage is unknown but may be related to the invasion of the calf by the bacteria. The challenge strain was isolated from the mesenteric lymph nodes of the same two calves but not from other organs or from heart blood. No blood was observed in the faeces of any of the three calves, nor were any lesions in the internal organs, which may have been related to the production of a verotoxin whose role is still unknown in cattle. [less ▲]

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See detailNatural case of bovine herpesvirus 1 meningoencephalitis in an adult cow.
Roels, S.; Charlier, G.; Letellier, C. et al

in Veterinary Record : Journal of the British Veterinary Association (2000), 146(20), 586-8

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See detailEpidemiologische bewaking van boviene spongiforme encefalopathie in Belgïe: Jaaroverzicht voor 1998
Saegerman, Claude ULg; Dechamps, P.; Vanopdenbosch, E. et al

in Vlaams Diergeneeskundig Tijdschrift (2000), 69

In 1998 werden 6 runderen tussen de 54 en 71 maanden ouderdom, afkomstig van de provincies West-Vlaanderen (3 gevallen), Oost-Vlaanderen (2 gevallen) en Luik (1 geval), gediagnostiseerd als gevallen van ... [more ▼]

In 1998 werden 6 runderen tussen de 54 en 71 maanden ouderdom, afkomstig van de provincies West-Vlaanderen (3 gevallen), Oost-Vlaanderen (2 gevallen) en Luik (1 geval), gediagnostiseerd als gevallen van boviene spongiforme encephalopathie (BSE). De hypotheses betreffende de oorsprong van de infectie op zijn de volgende : het optreden van sporadische gevallen zonder duidelijk definieerbare oorzaak; de mogelijke kruiscontaminatie tussen voeder voor monogastrische dieren met daarin dierlijk meel en voeder voor herkauwers waarin geen dierlijk meel is verwerkt en dit tijdens het fabricatieproces, de stockage, het transport of de distributie; het gebruik van dierlijk beendermeel in het voeder voor runderen geproduceerd voor de ban (van kracht vanaf 27/7/1994). Algemeen kan men dus stellen dat in België de aanwezigheid van gecontamineerd diermeel als risicofactor voor BSE niet kan worden uitgesloten. De oorsprong van deze diermelen kon nog niet gedetermineerd worden. [less ▲]

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See detailEpidémiosurveillance de l'encéphalopathie spongiforme bovine en Belgique : bilan de l'année 1998
Saegerman, Claude ULg; Dechamps, P.; Vanopdenbosch, E. et al

in Annales de Médecine Vétérinaire (1999), 143

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