title: Equine Herpesvirus-1 Myeloencephalopathy, an Emerging Threat of Working Equids in Ethiopia.
abstract: Although equine herpesvirus myeloencephalopathy (EHM) is a sporadic and relatively uncommon manifestation of equine herpesvirus-1 (EHV-1), it has the potential for causing devastating outbreaks in horses. Up till now, there were no reported EHM outbreaks in donkeys and mules. This study describes the isolation and molecular characterization of EHV-1 from clinically EHM-affected horses (n = 6), mules (n = 3) and donkeys (n = 82) in Ethiopia during outbreaks from May 2011 to December 2013. The incidence of EHM cases was higher from April to mid-June. EHM in donkeys was more severe and death without clinical signs of paralysis, and recumbency was frequently observed. The main age of affected equines ranged from 7 to 10 years (n = 51; 56.0%), and females (n = 58; 63.7%) were more affected than males. The incidence of neuropathogenic (D752) and non-neuropathogenic (N752) variants of EHV-1 from EHM-affected equines in Ethiopia was assessed by sequencing the DNA polymerase gene (ORF30) of the EHV-1 isolates. The results indicated that from the total of 91 clinically affected equines, 90 (98.9%) of them had an ORF30 D752genotype. An ORF30 N752variant was only found in one donkey. Analysis of ORF68 as grouping marker for geographical differences showed that the Ethiopian EHV-1 isolates belong to geographical group 4. Due to the fatal nature of EHV-1 in donkeys, it would be interesting to examine the pathogenesis of EHM in this species. At present, there is no vaccine available in Ethiopia, and therefore, outbreaks of EHV-1 should be controlled by proper management adaptations. In addition, it is important to test the efficacy of the commercial vaccines not only in horses, but also in donkeys and mules.
authors.affiliation: Laboratory of Virology, Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.|College of Veterinary Medicine and Agriculture, Addis Ababa University, Debre Ziet, Ethiopia.
authors.forename: H
authors.identifier: http://orcid.org/0000-0001-9313-5462
authors.initials: H
authors.lastname: Negussie
authors.affiliation: National Animal Health Diagnostic and Investigation Center, Sebeta, Ethiopia.
authors.forename: D
authors.initials: D
authors.lastname: Gizaw
authors.affiliation: Institute of Biotechnology, College of Natural and Computational Sciences, Addis Ababa University, Addis Ababa, Ethiopia.
authors.forename: T S
authors.initials: TS
authors.lastname: Tessema
authors.affiliation: Laboratory of Virology, Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: H J
authors.initials: HJ
authors.lastname: Nauwynck
mesh_terms: D000818:Animals; D004259:DNA-Directed DNA Polymerase / Q000235:genetics; D004196:Disease Outbreaks / Q000662:veterinary; D018397:Equidae / Q000821:virology*; D005002:Ethiopia / Q000453:epidemiology; D005260:Female; D005814:Genes, Viral / Q000235:genetics; D005838:Genotype; D006566:Herpesviridae Infections / Q000453:epidemiology*; D004861:Herpesvirus 1, Equid / Q000235:genetics / Q000302:isolation & purification*; D006734:Horse Diseases / Q000453:epidemiology / Q000821:virology*; D006736:Horses; D015994:Incidence; D008297:Male
chemical_list: D004259:DNA-Directed DNA Polymerase
keywords: Ethiopia; equine herpesvirus myeloencephalopathy; equine herpesvirus-1; equines; outbreaks