Molecular Surveillance of EHV-1 Strains Circulating in France during and after the Major 2009 Outbreak in Normandy Involving Respiratory Infection, Neurological Disorder, and Abortion

Gabrielle Sutton (1, 2) , Marie Garvey (3) , Ann Cullinane (3) , Marion Jourdan (4) , Christine Fortier (1, 2) , Peggy Moreau (5) , Marc Foursin (5) , Annick C. Gryspeerdt (6) , Virginie Maisonnier (4) , Christel Marcillaud Pitel (4) , Loïc Legrand (1, 2) , Romain Paillot (1, 2) , Stéphane Pronost (1, 2)

1 LABÉO - LABÉO, Pôle d’analyses et de recherche de Normandie
2 BIOTARGEN - Biologie, génétique et thérapies ostéoarticulaires et respiratoires
3 IEC - Irish Equine Centre
4 RESPE - Réseau d'Epidémio-Surveillance en Pathologie Équine
5 Clinique Équine de la Boisrie
6 Equi Focus Point Belgium

Equine herpesvirus 1 (EHV-1) is an Alphaherpesvirus infecting not only horses but also other equid and non-equid mammals. It can cause respiratory distress, stillbirth and neonatal death, abortion, and neurological disease. The different forms of disease induced by EHV-1 infection can have dramatic consequences on the equine industry, and thus the virus represents a great challenge for the equine and scientific community. This report describes the progress of a major EHV-1 outbreak that took place in Normandy in 2009, during which the three forms of disease were observed. A collection of EHV-1 strains isolated in France and Belgium from 2012 to 2018 were subsequently genetically analysed in order to characterise EHV-1 strain circulation. The open reading frame 30 (ORF30) non-neuropathogenic associated mutation A2254 was the most represented among 148 samples analysed in this study. ORF30 was also sequenced for 14 strains and compared to previously published sequences. Finally, a more global phylogenetic approach was performed based on a recently described Multilocus Sequence Typing (MLST) method. French and Belgian strains were clustered with known strains isolated in United Kingdom and Ireland, with no correlation between the phylogeny and the time of collection or location. This new MLST approach could be a tool to help understand epidemics in stud farms.

Mots clés: MLST; ORF30; abortion; equine herpesvirus type 1; myeloencephalopathy; neuropathogenic strain; outbreak; phylogeny; respiratory disease

Domaines: Médecine vétérinaire et santé animale; Génomique, Transcriptomique et Protéomique [q-bio.GN]; Biologie moléculaire

Gabrielle Sutton, Marie Garvey, Ann Cullinane, Marion Jourdan, Christine Fortier, et al.. Molecular Surveillance of EHV-1 Strains Circulating in France during and after the Major 2009 Outbreak in Normandy Involving Respiratory Infection, Neurological Disorder, and Abortion. Viruses, 2019, 11 (10), pp.916. ⟨10.3390/v11100916⟩. ⟨hal-02351539⟩