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  1. Article ; Online: Modelling the evolution of Schmallenberg virus seroprevalence in a sheep flock after natural infection.

    Claine, François / Coupeau, Damien / Wiggers, Laetitia / Muylkens, Benoît / Kirschvink, Nathalie

    Preventive veterinary medicine

    2018  Volume 154, Page(s) 132–138

    Abstract: Modelling the long-term seroprevalence evolution against Schmallenberg virus (SBV) is of first interest to plan vaccination strategies and to predict viral resurgence. The objectives of this study were first to estimate the duration of colostral immunity ...

    Abstract Modelling the long-term seroprevalence evolution against Schmallenberg virus (SBV) is of first interest to plan vaccination strategies and to predict viral resurgence. The objectives of this study were first to estimate the duration of colostral immunity and the persistence of active immunity in a sheep flock that encountered two episodes of natural SBV infection and then to model the evolution of SBV seroprevalence by considering immune status as well as zootechnical variables. The entire sheep flock of the University of Namur composed by around 400 ewes producing 600 lambs a year and characterized by an annual 24.0% renewal rate was used for this study from January 2012 until December 2016. Antibody titers were estimated by performing Virus Neutralization Test (VNT) from blood and colostrum samples collected in lambs and adult sheep. Colostral antibodies against SBV of lambs born to seropositive ewes were detectable during four months. A significant increase of anti-SBV antibody titers was observed in lambs' serum as well as in ewes' colostrum between the time of first viral episode (2011) and the time of SBV reemergence (2012) suggesting a booster effect of viral resurgence on immune status. In naturally SBV infected adult sheep, the active immunity was estimated to last at least four years. These results combined with flock management data allowed to develop a mathematical model to predict the evolution of SBV seroprevalence at a herd scale. The accuracy of this model was assessed by VNT experiment performed at the end of the study. By applying this model to the sheep flock of the University of Namur, it was estimated that an annual 24.0% renewal rate led to total seronegativity, and so high susceptibility to viral resurgence, in 50 months after time of last natural infection. The third SBV episode detected in this research sheep flock within the expected time demonstrated huge within-flock susceptibility.
    MeSH term(s) Animals ; Antibodies, Viral/blood ; Bunyaviridae Infections/epidemiology ; Bunyaviridae Infections/veterinary ; Bunyaviridae Infections/virology ; Female ; Orthobunyavirus ; Seroepidemiologic Studies ; Sheep ; Sheep Diseases/epidemiology ; Sheep Diseases/virology
    Chemical Substances Antibodies, Viral
    Language English
    Publishing date 2018-03-31
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 43399-8
    ISSN 1873-1716 ; 0167-5877
    ISSN (online) 1873-1716
    ISSN 0167-5877
    DOI 10.1016/j.prevetmed.2018.03.024
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: Epigenetic Silencing of MicroRNA-126 Promotes Cell Growth in Marek's Disease.

    Gennart, Isabelle / Petit, Astrid / Wiggers, Laetitia / Pejaković, Srđan / Dauchot, Nicolas / Laurent, Sylvie / Coupeau, Damien / Muylkens, Benoît

    Microorganisms

    2021  Volume 9, Issue 6

    Abstract: During latency, herpesvirus infection results in the establishment of a dormant state in which a restricted set of viral genes are expressed. Together with alterations of the viral genome, several host genes undergo epigenetic silencing during latency. ... ...

    Abstract During latency, herpesvirus infection results in the establishment of a dormant state in which a restricted set of viral genes are expressed. Together with alterations of the viral genome, several host genes undergo epigenetic silencing during latency. These epigenetic dysregulations of cellular genes might be involved in the development of cancer. In this context, Gallid alphaherpesvirus 2 (GaHV-2), causing Marek's disease (MD) in susceptible chicken, was shown to impair the expression of several cellular microRNAs (miRNAs). We decided to focus on gga-miR-126, a host miRNA considered a tumor suppressor through signaling pathways controlling cell proliferation. Our objectives were to analyze the cause and the impact of miR-126 silencing during GaHV-2 infection. This cellular miRNA was found to be repressed at crucial steps of the viral infection. In order to determine whether miR-126 low expression level was associated with specific epigenetic signatures, DNA methylation patterns were established in the miR-126 gene promoter. Repression was associated with hypermethylation at a CpG island located in the miR-126 host gene epidermal growth factor like-7 (
    Language English
    Publishing date 2021-06-21
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2720891-6
    ISSN 2076-2607
    ISSN 2076-2607
    DOI 10.3390/microorganisms9061339
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Role of DNA Methylation and CpG Sites in the Viral Telomerase RNA Promoter during Gallid Herpesvirus 2 Pathogenesis.

    Pejaković, Srđan / Mbouombouo Mfossa, André Claude / Wiggers, Laëtitia / Kheimar, Ahmed / Coupeau, Damien / Kaufer, Benedikt B / Muylkens, Benoît

    Journal of virology

    2020  Volume 94, Issue 23

    Abstract: Gallid herpesvirus type 2 (GaHV-2) is an oncogenic alphaherpesvirus that induces malignant T-cell lymphoma in chicken. GaHV-2 encodes a viral telomerase RNA subunit (vTR) that plays a crucial role in virus-induced tumorigenesis, enhances telomerase ... ...

    Abstract Gallid herpesvirus type 2 (GaHV-2) is an oncogenic alphaherpesvirus that induces malignant T-cell lymphoma in chicken. GaHV-2 encodes a viral telomerase RNA subunit (vTR) that plays a crucial role in virus-induced tumorigenesis, enhances telomerase activity, and possesses functions independent of the telomerase complex. vTR is driven by a robust viral promoter, highly expressed in virus-infected cells, and regulated by two c-Myc response elements (c-Myc REs). The regulatory mechanisms involved in controlling vTR and other genes during viral replication and latency remain poorly understood but are crucial to understanding this oncogenic herpesvirus. Therefore, we investigated DNA methylation patterns of CpG dinucleotides found in the vTR promoter and measured the impact of methylation on telomerase activity. We demonstrated that telomerase activity was considerably increased following viral reactivation. Furthermore, CpG sites within c-Myc REs showed specific changes in methylation after
    MeSH term(s) Animals ; Carcinogenesis/genetics ; Cell Line ; Chickens ; DNA Methylation/physiology ; Gene Expression Regulation, Viral ; Herpesvirus 2, Gallid/enzymology ; Herpesvirus 2, Gallid/genetics ; Herpesvirus 2, Gallid/pathogenicity ; Marek Disease/virology ; Mutagenesis, Site-Directed ; Mutation ; Promoter Regions, Genetic ; RNA ; RNA, Viral/genetics ; Telomerase/genetics ; Virus Replication
    Chemical Substances RNA, Viral ; telomerase RNA ; RNA (63231-63-0) ; Telomerase (EC 2.7.7.49)
    Language English
    Publishing date 2020-11-09
    Publishing country United States
    Document type Journal Article
    ZDB-ID 80174-4
    ISSN 1098-5514 ; 0022-538X
    ISSN (online) 1098-5514
    ISSN 0022-538X
    DOI 10.1128/JVI.01488-20
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Improved measurements of phosphorus loss to watercourses from agricultural areas

    Wiggers, L

    Phosphorus loss from soil to water / 1997.

    1997  

    Keywords water resources ; water management ; natural resources ; waste management ; pollution ; environmental degradation
    Language English
    Size p. 394-396.
    Publisher CAB International, c1997.
    Publishing place Wallingford, UK ; New York
    Document type Article
    Note Proceedings of a workshop held September 29-31, 1995, Wexford, Ireland / edited by H. Tunney, O.T. Carton, P.C. Brookes, and A.E. Johnson.
    ISBN 0851991564 ; 9780851991566
    Database NAL-Catalogue (AGRICOLA)

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  5. Article ; Online: Schmallenberg virus infection of ruminants

    Claine F / Coupeau D / Wiggers L / Muylkens B / Kirschvink N

    Veterinary Medicine: Research and Reports, Vol 2015, Iss default, Pp 261-

    challenges and opportunities for veterinarians

    2015  Volume 272

    Abstract: François Claine, Damien Coupeau, Laetitia Wiggers, Benoît Muylkens, Nathalie Kirschvink Veterinary Department, Faculty of Sciences, Namur Research Institute for Life Sciences (NARILIS), University of Namur (UNamur), Namur, Belgium Abstract: In 2011, ... ...

    Abstract François Claine, Damien Coupeau, Laetitia Wiggers, Benoît Muylkens, Nathalie Kirschvink Veterinary Department, Faculty of Sciences, Namur Research Institute for Life Sciences (NARILIS), University of Namur (UNamur), Namur, Belgium Abstract: In 2011, European ruminant flocks were infected by Schmallenberg virus (SBV) leading to transient disease in adult cattle but abortions and congenital deformities in calves, lambs, and goat kids. SBV belonging to the Simbu serogroup (family Bunyaviridae and genus Orthobunyavirus) was first discovered in the same region where bluetongue virus serotype 8 (BTV-8) emerged 5 years before. Both viruses are transmitted by biting midges (Culicoides spp.) and share several similarities. This paper describes the current knowledge of temporal and geographical spread, molecular virology, transmission and susceptible species, clinical signs, diagnosis, prevention and control, impact on ruminant health, and productivity of SBV infection in Europe, and compares SBV infection with BTV-8 infection in ruminants. Keywords: Schmallenberg virus, Europe, ruminants, review
    Keywords Veterinary medicine ; SF600-1100
    Language English
    Publishing date 2015-06-01T00:00:00Z
    Publisher Dove Medical Press
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: Test selection for antibody detection according to the seroprevalence level of Schmallenberg virus in sheep.

    Pejaković, Srđan / Wiggers, Laëtitia / Coupeau, Damien / Kirschvink, Nathalie / Mason, James / Muylkens, Benoît

    PloS one

    2018  Volume 13, Issue 4, Page(s) e0196532

    Abstract: Schmallenberg virus (SBV), initially identified in Germany in 2011, spread rapidly throughout Europe causing significant economic losses in ruminant livestock. The ability to correctly detect emerging and re-emerging diseases such as SBV with reliable ... ...

    Abstract Schmallenberg virus (SBV), initially identified in Germany in 2011, spread rapidly throughout Europe causing significant economic losses in ruminant livestock. The ability to correctly detect emerging and re-emerging diseases such as SBV with reliable tests is of high importance. Firstly, we tested diagnostic performance, specificity, and sensitivity of three different assays used in SBV antibody detection using control sheep samples of determined status. After obtaining the results from the control samples, we assessed the potential of the assays to detect previously infected animals in field situations. The samples were investigated using IDEXX Schmallenberg virus Antibody Test Kit, ID Screen Schmallenberg virus Competition Multi-species ELISA and Serum Neutralisation Test (SNT). Analysis of control samples revealed that SNT was the most suitable test, which was therefore used to calculate concordance and test performance for the two other ELISA tests. To evaluate whether different assay performances had an impact under field conditions, sheep samples from two different contexts were tested: the emergence of SBV in Ireland and the re-emergence of SBV in Belgium. Comparing the results obtained from different assays to the non-reference standard assay SNT, we showed considerable differences in estimates of their sensitivity to detect SBV antibodies and to measure seroprevalence of the sheep flocks. Finally, a calculation of the number of randomly selected animals that needs to be screened from a finite flock, showed that SNT and ID.Vet are the most suitable to detect an introduction of the disease in low seroprevalence situations. The IDEXX ELISA test was only able to detect SBV antibodies in a higher seroprevalence context, which is not optimal for monitoring freedom of disease and surveillance studies.
    MeSH term(s) Animals ; Antibodies, Viral/blood ; Belgium ; Bunyaviridae Infections/blood ; Bunyaviridae Infections/veterinary ; Enzyme-Linked Immunosorbent Assay/veterinary ; Germany ; Immunologic Tests ; Ireland ; Neutralization Tests/instrumentation ; Neutralization Tests/methods ; Orthobunyavirus ; Sensitivity and Specificity ; Seroepidemiologic Studies ; Sheep/blood ; Sheep/virology ; Sheep Diseases/blood ; Sheep Diseases/virology
    Chemical Substances Antibodies, Viral
    Language English
    Publishing date 2018
    Publishing country United States
    Document type Journal Article
    ISSN 1932-6203
    ISSN (online) 1932-6203
    DOI 10.1371/journal.pone.0196532
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: S segment variability during the two first years of the spread of Schmallenberg virus.

    Coupeau, Damien / Claine, François / Wiggers, Laetitia / Kirschvink, Nathalie / Muylkens, Benoît

    Archives of virology

    2016  Volume 161, Issue 5, Page(s) 1353–1358

    Abstract: A large sheep flock screened over a two-year period showed active spreading of Schmallenberg virus (SBV) during the summers of 2011 and 2012. Transplacental infections were observed during the two associated lambing periods (the winters of 2012 and 2013). ...

    Abstract A large sheep flock screened over a two-year period showed active spreading of Schmallenberg virus (SBV) during the summers of 2011 and 2012. Transplacental infections were observed during the two associated lambing periods (the winters of 2012 and 2013). Analysis of small (S) segment sequences of 38 SBV-positive samples, collected during periods of viral spreading and lambing revealed intra-herd sequences diversity and sub-consensus variability occurring after transplacental infections. In comparison with the nucleoprotein (N), which appeared to be conserved, the non-structural protein (NSs) showed the highest level of variability at the time of viral emergence and over the two-year analysis period.
    MeSH term(s) Animals ; Bunyaviridae Infections/veterinary ; Bunyaviridae Infections/virology ; Genetic Variation/genetics ; Open Reading Frames/genetics ; Orthobunyavirus/genetics ; RNA, Viral/genetics ; Sheep ; Sheep Diseases/virology
    Chemical Substances RNA, Viral
    Language English
    Publishing date 2016-05
    Publishing country Austria
    Document type Journal Article
    ZDB-ID 7491-3
    ISSN 1432-8798 ; 0304-8608
    ISSN (online) 1432-8798
    ISSN 0304-8608
    DOI 10.1007/s00705-016-2787-x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Schmallenberg virus infection of ruminants: challenges and opportunities for veterinarians.

    Claine, François / Coupeau, Damien / Wiggers, Laetitia / Muylkens, Benoît / Kirschvink, Nathalie

    Veterinary medicine (Auckland, N.Z.)

    2015  Volume 6, Page(s) 261–272

    Abstract: In 2011, European ruminant flocks were infected by Schmallenberg virus (SBV) leading to transient disease in adult cattle but abortions and congenital deformities in calves, lambs, and goat kids. SBV belonging to the Simbu serogroup (family Bunyaviridae ... ...

    Abstract In 2011, European ruminant flocks were infected by Schmallenberg virus (SBV) leading to transient disease in adult cattle but abortions and congenital deformities in calves, lambs, and goat kids. SBV belonging to the Simbu serogroup (family Bunyaviridae and genus
    Language English
    Publishing date 2015-06-29
    Publishing country New Zealand
    Document type Journal Article ; Review
    ISSN 2230-2034
    ISSN (online) 2230-2034
    DOI 10.2147/VMRR.S83594
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Schmallenberg virus among female lambs, Belgium, 2012.

    Claine, François / Coupeau, Damien / Wiggers, Laetitia / Muylkens, Benoît / Kirschvink, Nathalie

    Emerging infectious diseases

    2013  Volume 19, Issue 7, Page(s) 1115–1117

    Abstract: Reemergence of Schmallenberg virus (SBV) occurred among lambs (n = 50) in a sheep flock in Belgium between mid-July and mid-October 2012. Bimonthly assessment by quantitative reverse transcription PCR and seroneutralization demonstrated that 100% of ... ...

    Abstract Reemergence of Schmallenberg virus (SBV) occurred among lambs (n = 50) in a sheep flock in Belgium between mid-July and mid-October 2012. Bimonthly assessment by quantitative reverse transcription PCR and seroneutralization demonstrated that 100% of lambs were infected. Viremia duration may be longer in naturally infected than in experimentally infected animals.
    MeSH term(s) Animals ; Belgium/epidemiology ; Bunyaviridae Infections/epidemiology ; Bunyaviridae Infections/veterinary ; Bunyaviridae Infections/virology ; Communicable Diseases, Emerging/epidemiology ; Communicable Diseases, Emerging/veterinary ; Communicable Diseases, Emerging/virology ; Disease Outbreaks ; Female ; Genes, Viral ; Molecular Diagnostic Techniques ; Orthobunyavirus/genetics ; Prevalence ; Real-Time Polymerase Chain Reaction ; Seroepidemiologic Studies ; Sheep ; Sheep Diseases/epidemiology ; Sheep Diseases/virology ; Sheep, Domestic/virology
    Language English
    Publishing date 2013-06-13
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1380686-5
    ISSN 1080-6059 ; 1080-6040
    ISSN (online) 1080-6059
    ISSN 1080-6040
    DOI 10.3201/eid1907.121768
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: In vivo and in vitro identification of a hypervariable region in Schmallenberg virus.

    Coupeau, Damien / Claine, François / Wiggers, Laetitia / Kirschvink, Nathalie / Muylkens, Benoît

    The Journal of general virology

    2013  Volume 94, Issue Pt 6, Page(s) 1168–1174

    Abstract: Detected for the first time in 2011, Schmallenberg virus (SBV) is an orthobunyavirus of the Simbu serogroup that caused a large outbreak in European ruminants. In a tight time frame, data have been obtained on SBV epidemiology and the clinical pictures ... ...

    Abstract Detected for the first time in 2011, Schmallenberg virus (SBV) is an orthobunyavirus of the Simbu serogroup that caused a large outbreak in European ruminants. In a tight time frame, data have been obtained on SBV epidemiology and the clinical pictures associated with this new viral infection, but little information is available on the molecular biology of SBV. In this study, SBV sequence variability was characterized from the central nervous system of two stillborn lambs in a naturally infected herd. A hypervariable region (HVR) was detected in the N-terminal region of the SBV Gc glycoprotein through sequencing and analysis of the two full-length genomes representative of intra-herd SBV dissemination. In vitro growth assays coupled with full-length genome sequencing were performed on the two isolates after successive cellular passages, showing an in vitro adaptation of SBV and mutation accumulation inside the HVR in the absence of immune selective pressure.
    MeSH term(s) Animals ; Base Sequence ; Bunyaviridae Infections/veterinary ; Bunyaviridae Infections/virology ; Genetic Variation ; Glycoproteins/genetics ; Molecular Sequence Data ; Mutation ; Orthobunyavirus/genetics ; Orthobunyavirus/isolation & purification ; Sheep ; Sheep Diseases/virology ; Viral Proteins/genetics
    Chemical Substances Glycoproteins ; Viral Proteins
    Language English
    Publishing date 2013-01-30
    Publishing country England
    Document type Journal Article
    ZDB-ID 219316-4
    ISSN 1465-2099 ; 0022-1317
    ISSN (online) 1465-2099
    ISSN 0022-1317
    DOI 10.1099/vir.0.051821-0
    Database MEDical Literature Analysis and Retrieval System OnLINE

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