Publications by authors named "Emmanuel Breard"

Article Synopsis
  • - Bluetongue (BT) and Epizootic Hemorrhagic Disease (EHD) are important animal diseases impacting cattle and sheep, caused by viruses transmitted by biting midges, with recent outbreaks noted in France during the summer of 2023.
  • - Genomic analysis revealed three viruses involved in the outbreaks: EHDV-8, which matches strains found in southern Europe since 2021, and two different strains of BTV, including a novel BTV-8 strain and an established BTV-4 strain.
  • - The 2023 outbreaks indicate unusual dynamics in the circulation and emergence of these viruses in France, prompting further investigation into the epidemiological factors contributing to their spread.
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Article Synopsis
  • Viral diseases can have different clinical outcomes based on the virus strain and individual host responses; understanding these differences is crucial for developing therapies and prognostic markers.
  • The study focused on the bluetongue virus in sheep, exploring how variations in the virus lead to a range of clinical symptoms, from mild to severe disease.
  • Researchers used machine learning to analyze 332 parameters, identifying five key processes (virus replication, immune response modulation, inflammation, vascular damage, and immunosuppression) that influence the severity of bluetongue infections.
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The emergence of EHDV in Europe during the autumn of 2022 reinforces the need for molecular tools (RT-PCR) for rapid detection of animals infected with this virus. Viral genome testing can be performed on whole blood under anticoagulant, spleen, and bloody organ homogenates from ruminants. It can also be performed on cell culture following viral isolation tests.

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Real-time RT-PCR for the detection of epizootic hemorrhagic disease virus (EHDV) in clinical samples is a fast and sensitive tool for the diagnosis and confirmation of disease. Several real-time RT-PCR methods have been reported over the last 10 years. In this chapter, we describe seven duplex real-time RT-PCR assays to amplify part of genome segment 2 of EHDV to enable serotype identification.

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Article Synopsis
  • A study conducted in western Cuba aimed to identify circulating bluetongue virus (BTV) serotypes in cattle and sheep, after discovering a high prevalence of the virus in the region.
  • Blood samples from 200 animals were analyzed using various virological techniques, confirming a 25% prevalence rate and identifying twelve different BTV serotypes (BTV-1, 2, 3, 6, 10, 12, 13, 17, 18, 19, 22, and 24).
  • The research highlighted the diverse presence of BTV serotypes in a limited area, indicating the importance of ongoing monitoring and surveillance of livestock and insect populations due to evolving global patterns of BTV
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Article Synopsis
  • - EHDV-8, a virus that affects livestock, was first identified in Europe in late 2022, and this study examined its effects on cattle, sheep, and goats after experimental infection.
  • - Infected calves mostly showed symptoms such as fever and lesions, with RNA levels peaking at 7 days post infection and remaining stable for the study's duration, while some sheep exhibited fever and consistent RNAemia, but goats showed no RNA presence.
  • - All species developed an immune response, with calves showing the strongest, indicating that sheep could also be significant in spreading EHDV-8, which is essential information for developing disease control strategies in livestock.
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The circulation of Bluetongue (BT) and Epizootic Hemorrhagic Disease (EHD) in the Middle East has already been reported following serological analyses carried out since the 1980s, mostly on wild ruminants. Thus, an EHD virus (EHDV) strain was isolated in Bahrain in 1983 (serotype 6), and more recently, BT virus (BTV) serotypes 1, 4, 8 and 16 have been isolated in Oman. To our knowledge, no genomic sequence of these different BTV strains have been published.

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We describe the detection of epizootic hemorrhagic disease virus (EHDV) serotype 8 in cattle farms in Sardinia and Sicily in October-November 2022. The virus has a direct origin in North Africa; its genome is identical (>99.9% nucleotide sequence identity) to EHDV serotype 8 strains detected in Tunisia in 2021.

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Epizootic hemorrhagic disease (EHD) is a non-contagious arthropod-borne disease transmitted by blood-sucking midges of the genus Culicoides. It affects domestic and wild ruminants, mainly white-tailed deer and cattle. At the end of October and in November 2022, outbreaks of EHD were confirmed in several cattle farms in Sardinia and Sicily.

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Epizootic hemorrhagic disease (EHD) is a non-contagious arthropod-borne disease transmitted by blood-sucking midges of the genus Culicoides. It affects domestic and wild ruminants, mainly white-tailed deer and cattle. At the end of October and in November 2022, outbreaks of EHD were confirmed in several cattle farms in Sardinia and Sicily.

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Epizootic haemorrhagic disease (EHD) is a -borne viral disease caused by the epizootic haemorrhagic disease virus (EHDV) associated with clinical manifestations in domestic and wild ruminants, primarily white-tailed deer () and cattle (). In late September 2021, EHDV was reported in cattle farms in central/western Tunisia. It rapidly spread throughout the country with more than 200 confirmed outbreaks.

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Since the outbreak of bluetongue in Northern Europe in 2006, numerous outbreaks involving several serotypes have been observed. Since 2008, compulsory or voluntary vaccination campaigns with inactivated vaccines have been carried out to eradicate these serotypes. In France, serotypes 8 and 4 have been enzootic since 2017, and currently, the majority of vaccinations take place in the context of animal movements, to comply with the regulations of the importing countries.

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African horse sickness (AHS) is a major arthropod-borne disease that causes significant losses in horses in sub-Saharan Africa. It is caused by the African horse sickness virus (AHSV), which is transmitted during a blood meal by Culicoides biting midges. The distribution of historical African culicoid vectors increases due to global warming.

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Bluetongue (BT) is an infectious, arthropod-borne viral disease of domestic and wild ruminants. The disease causes animal mortality, production decrease and commercial limits for herds. Despite the active circulation of the disease in the world, few studies have been carried out in Senegal.

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Bluetongue virus (BTV) is the etiologic agent of a non-contagious arthropod-borne disease transmitted to wild and domestic ruminants. BTV induces a large panel of clinical manifestations ranging from asymptomatic infection to lethal hemorrhagic fever. Despite the fact that BTV has been studied extensively, we still have little understanding of the molecular determinants of BTV virulence.

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In this article, we describe the development and evaluation of a double antigen sandwich enzyme-linked immunosorbent assay (ELISA) able to detect serotype 4-specific antibodies from BTV-4 infected or vaccinated animals using a recombinant BTV-4 VP2 protein. The coding sequence of VP2 was inserted into a pVote plasmid by recombination in the Gateway cloning system. Vaccinia virus (VacV) was used as a vector for the expression of the recombinant VP2.

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Bluetongue virus (BTV), an arbovirus transmitted by biting midges, is a major concern of wild and domestic ruminants. While BTV induces type I interferon (alpha/beta interferon [IFN-α/β]) production in infected cells, several reports have described evasion strategies elaborated by this virus to dampen this intrinsic, innate response. In the present study, we suggest that BTV VP3 is a new viral antagonist of the IFN-β synthesis.

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Genome segmentation is mainly thought to facilitate reassortment. Here, we show that segmentation can also allow differences in segment abundance in populations of bluetongue virus (BTV). BTV has a genome consisting in 10 segments, and its cycle primarily involves periodic alternation between ruminants and biting midges.

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Article Synopsis
  • Virus emergence mechanisms are often unclear, making outbreaks unpredictable, as seen with the Bluetongue virus serotype 8 (BTV-8) outbreaks in Europe, which began in 2006 and re-emerged in 2015 despite prior control efforts.
  • Phylogenetic analysis of 164 BTV-8 genomes revealed minimal evolutionary change between the two outbreaks, suggesting that the virus did not replicate for several years during this period.
  • The researchers propose that the second outbreak may have been triggered by livestock exposure to frozen virus-contaminated materials from the earlier outbreak, underlining the need for improved disease surveillance in livestock and demonstrating the value of genomic studies in understanding infectious diseases.
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Bluetongue (BT) and epizootic haemorrhagic disease (EHD) are vector-borne viral diseases affecting domestic and wild ruminants. Both are notifiable under OIE rules. BT and EHD viruses (BTV and EHDV) are closely related Orbiviruses with structural, antigenic and molecular similarities.

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The aim of this study was to produce reference sera against the seven serotypes of Epizootic hemorrhagic disease virus (EHDV‑1, EHDV‑2, EHDV‑4, EHDV‑5, EHDV‑6, EHDV‑7, and EHDV‑8). In a high containment unit, seven Prim 'Holstein calves were inoculated at day 0 (D0) with the selected strains (1 EHDV serotype per calf ). Blood samples (EDTA and whole blood) were periodically taken from D0 until the end of the experiment (D31).

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Bluetongue virus serotype 8 (BTV-8) caused an epizootic in Europe in 2006/09. Transplacental transmission of BTV-8 was demonstrated leading to abortions, congenital malformations or nervous clinical signs in newborn calves. BTV-8 re-emerged in France in 2015.

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Bluetongue virus (BTV) is a -borne pathogen infecting both domestic and wild ruminants. In Europe, the Red Deer () (RD) is considered a potential BTV reservoir, but persistent sylvatic cycle has not yet been demonstrated. In this paper, we explored the dynamics of BTV1 and BTV8 serotypes in the RD in France, and the potential role of that species in the re-emergence of BTV8 in livestock by 2015 (i.

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