Epidemiology of equine infectious anemia in France and in Europe from 1994 to 2011

Equine Infectious Anaemia (EIA) is a viral disease affecting horses, mules, and donkeys. The virus, present worldwide, is a member of the Retroviridae family, genus Lentivirus, such as the Human Immunodeficiency Virus (HIV). It causes a persistent infection, often associated with recurrent clinical episodes characterized by viremia, fever, and anaemia. Asymptomatic infected animals serve as a reservoir for the virus and are contagious. EIA is endemic in Romania, whereas only sporadic cases have been notified in others European countries. To improve understanding and prevention of the viral and disease spread within the equine population, epidemiological surveys as well as molecular characterisation of strains isolated in Europe are required.L'Anémie Infectieuse des Equidés (AIE) est une maladie virale qui affecte les chevaux, les mulets et les ânes. Le virus responsable, présent dans le monde entier, de la maladie appartient à la famille des Retroviridae, genre lentivirus comme le Virus de l'Immunodéficience Humaine (VIH). Il provoque une infection persistante, souvent associée à des épisodes cliniques récurrents caractérisés par une viré-mie, de la fièvre et de l'anémie. Les animaux infectés asymptomatiques représentent le réservoir du virus et sont contagieux. La Roumanie et l'Italie sont les deux pays européens les plus touchés par la maladie seuls des cas sporadiques sont déclarés dans le reste de l'Europe. Afin de mieux comprendre et de mieux prévenir la dissémination du virus et de la maladie au sein de la population équine des enquêtes épidémiologiques et des études de caractérisation moléculaire des souches isolées en Europe sont nécessaires

Genetic evolution of equine influenza virus strains (H3N8) isolated in France from 1967 to 2015 and the implications of several potential pathogenic factors

International audienceEquine influenza virus (EIV) is a major respiratory pathogen of horses despite the availability of equine influenza vaccines. This study aimed to determine genetic evolution of EIV strains in France between 1967 to present. A whole genome comparative analysis was also conducted on recent French strains in order to identify potential factors of pathogenicity. Comparison of French EIV sequences with vaccine and worldwide epidemic strains revealed amino acid substitutions in both haemagglutinin (HA) and neuraminidase, especially within the antigenic sites and/or close to receptor binding sites (HA). Amino acid substitutions were also identified in other genes, mainly the polymerase complex proteins and PB1-F2. Viruses belonging to Eurasian and American lineages have circulated until 2003 and Florida sub-lineage Clade 2 strains predominates since 2005. The last French strain (2015) displayed several specificities in HA suggesting the occurrence of antigenic drift with presence of pathogenic markers in the PA and PB1-F2 genes

Emergence of novel equine arteritis virus (EAV) variants during persistent infection in the stallion: Origin of the 2007 French EAV outbreak was linked to an EAV strain present in the semen of a persistently infected carrier stallion

AbstractDuring the summer of 2007, an outbreak of equine viral arteritis (EVA) occurred in Normandy (France). After investigation, a link was suggested between an EAV carrier stallion (A) and the index premise of the outbreak. The full-length nucleotide sequence analysis of a study reference strain (F27) isolated from the lung of a foal revealed a 12,710 nucleotides EAV genome with unique molecular hallmarks in the 5′UTR leader sequence and the ORF1a sequence encoding the non-structural protein 2. The evolution of the viral population in the persistently infected Stallion A was then studied by cloning ORFs 3 and 5 of the EAV genome from four sequential semen samples which were collected between 2000 and 2007. Molecular analysis of the clones confirmed the likely implication of Stallion A in the origin of this outbreak through the yearly emergence of new variants genetically similar to the F27 strain

Analysis of Two New Arabinosyltransferases Belonging to the Carbohydrate-Active Enzyme (CAZY) Glycosyl Transferase Family1 Provides Insights into Disease Resistance and Sugar Donor Specificity

Glycosylation of small molecules is critical for numerous biological processes in plants, including hormone homeostasis, neutralization of xenobiotics, and synthesis and storage of specialized metabolites. Glycosylation of plant natural products is usually carried out by uridine diphosphate-dependent glycosyltransferases (UGTs). Triterpene glycosides (saponins) are a large family of plant natural products that determine important agronomic traits such as disease resistance and flavor and have numerous pharmaceutical applications. Most characterised plant natural product UGTs are glucosyltransferases, and little is known about enzymes that add other sugars. Here we report the discovery and characterization of AsAAT1 (UGT99D1), which is required for biosynthesis of the antifungal saponin avenacin A-1 in oat. This enzyme adds L-arabinose to the triterpene scaffold at the C-3 position, a modification critical for disease resistance. The only previously reported plant natural product arabinosyltransferase is a flavonoid arabinosyltransferase from Arabidopsis. We show that AsAAT1 has high specificity for UDP-β-L-arabinopyranose, identify two amino acids required for sugar donor specificity, and through targeted mutagenesis convert AsAAT1 into a glucosyltransferase. We further identify a second arabinosyltransferase potentially implicated in the biosynthesis of saponins that determine bitterness in soybean. Our investigations suggest independent evolution of UDP-arabinose sugar donor specificity in arabinosyltransferases in monocots and eudicots

La pathologie, vers un meilleur suivi sanitaire

National audienc

La pathologie, vers un meilleur suivi sanitaire

National audienc

Etude des conséquences de l'infection par le bornavirus sur la physiologie neuronale

PARIS-BIUSJ-Thèses (751052125) / SudocPARIS-BIUSJ-Physique recherche (751052113) / SudocSudocFranceF

Molecular characterization of Equine Infectious Anemia Viruses using targeted sequence enrichment and next generation sequencing

International audienceEquine infectious anemia virus (EIAV) is responsible of acute disease episodes characterized by fever, anemia, thrombocytopenia and anorexia in equids. The high mutation rate in EIAV genome limited the number of full genome sequences availability. In the present study, we used the SureSelect target enrichment system with Illumina Next Generation Sequencing to characterize the proviral DNA of Equine Infectious Anemia Virus (EIAV) from asymptomatic horses. This approach allows a direct sequencing of the EIAV whole genome without cloning or amplification steps and we could obtain for the first time the complete genomic DNA sequences of French EIAV strains. We analyzed their phylogenetic relationship and genetic variability by comparison with 17 whole EIAV genome sequences from different parts of the world. The results obtained provide new insights into the molecular detection of EIAV and genetic diversity of European viral strains

Prévalence des herpès virus équins en France au cours de l’année 2010

Five herpesviruses are currently known to be pathogenic to horses: equine herpesviruses 1, 3 and 4 (subfamily Alphaherpesvirinae) and equine herpesviruses 2 and 5 (subfamily Gammaherpesvirinae). Equine herpesvirus 1— one of the major infectious agents in horses—is responsible for three distinct clinical forms: respiratory, abortive and neurological. The other herpesviruses generally cause respiratory symptoms, in particular equine herpesvirus 4, the main agent of rhinopneumonitis. The multiplicity of clinical forms induced by the infection led the French network for epidemiological surveillance of equine diseases (RESPE) to include some of these viruses in its surveillance programme. Accordingly, herpesvirus 1 is closely monitored by the “neurological syndrome” sub-network whereas only herpesviruses 1 and 4 are screened for in the “abortion” and “acute respiratory syndrome” protocols. All the data collected were analysed to assess the incidence of these viruses throughout 2010. This analysis confirmed the major role played by herpesvirus 1 in both abortions and, more importantly, encephalomyelitis—particularly during a major animal epidemic in the Val d’Oise département. Herpesvirus 4 is mainly found in cases of acute respiratory syndrome.Cinq herpèsvirus sont connus à ce jour comme pathogènes chez le cheval : les herpèsvirus équins 1, 3 et 4 (sous-famille des Alphaherpesvirinae) et les herpèsvirus équins 2 et 5 (sousfamille des Gammaherpesvirinae). L’herpèsvirus équin 1, l’un des agents infectieux majeurs du cheval, est responsable de trois formes cliniques bien distinctes : une forme respiratoire, une forme abortive et une forme neurologique. Les autres herpèsvirus sont généralement responsables de symptômes respiratoires, notamment l’herpèsvirus équin 4, agent principal de la rhinopneumonie. La multiplicité des formes cliniques induites par l’infection a conduit le Réseau d’épidémiosurveillance en pathologie équine (RESPE) à inclure certains de ces virus à leur programme de surveillance. Ainsi, l’herpèsvirus 1 est particulièrement suivi par le sous-réseau appelé « syndrome neurologique », alors que seuls les herpèsvirus 1 et 4 sont recherchés dans les protocoles « avortement » et « syndrome respiratoire aigu ». L’ensemble des données collectées a ainsi pu être analysé pour permettre d’évaluer l’incidence de ces virus au cours de l’année 2010. Cette analyse a confirmé l’importance de l’herpèsvirus 1 dans les cas d’avortement, mais surtout lors d’encéphalomyélite et, notamment, lors d’une épizootie majeure survenue dans le Val-d’Oise. L’herpèsvirus 4 est surtout retrouvé dans les cas de syndrome respiratoire aigu