title: A severe equine herpesvirus type 1 (EHV-1) abortion outbreak caused by a neuropathogenic strain at a breeding farm in northern Germany.
abstract: A particularly severe equine herpesvirus type 1 (EHV-1) abortion outbreak occurred at a breeding farm in northern Germany. Sixteen of 25 pregnant mares that had received regular vaccination using an inactivated vaccine aborted and two gave birth to weak non-viable foals in a span of three months, with 89% of cases occurring within 40 days after the initial abortion case. Virological examinations revealed the presence of EHV-1 in all cases of abortion and serological follow-up in mares confirmed recent infection. Molecular studies identified a neuropathogenic variant (Pol/ORF30 A2254 to G2254) that belonged to geographical group 4 of EHV-1 isolates. The abortion outbreak was preceded by a case of mild ataxia of unknown cause in a mare that aborted four months after the ataxic episode. Although vaccination of pregnant mares did not prevent abortion, good EHV-1 immune status of the population at the time of outbreak may have had an impact in the failure of manifestation of the neurological form of the disease.
authors.affiliation: Institut für Virologie, Zentrum für Infektionsmedizin, Robert von Ostertag-Haus, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163 Berlin, Germany. Electronic address: adamiani@zedat.fu-berlin.de.
authors.forename: Armando Mario
authors.initials: AM
authors.lastname: Damiani
authors.affiliation: Institut für Virologie, Zentrum für Infektionsmedizin, Robert von Ostertag-Haus, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163 Berlin, Germany.
authors.forename: Maren
authors.initials: M
authors.lastname: de Vries
authors.affiliation: Pferde-Praxis Ahrensburg, Haberkamp 3, 22927 Großhansdorf, Germany.
authors.forename: Gitta
authors.initials: G
authors.lastname: Reimers
authors.affiliation: Pferde-Praxis Ahrensburg, Haberkamp 3, 22927 Großhansdorf, Germany.
authors.forename: Sonja
authors.initials: S
authors.lastname: Winkler
authors.affiliation: Institut für Virologie, Zentrum für Infektionsmedizin, Robert von Ostertag-Haus, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163 Berlin, Germany.
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Osterrieder
mesh_terms: D000034:Abortion, Veterinary / Q000453:epidemiology / Q000821:virology*; D000818:Animals; D004196:Disease Outbreaks / Q000662:veterinary; D005260:Female; D005858:Germany / Q000453:epidemiology; D006566:Herpesviridae Infections / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D004861:Herpesvirus 1, Equid / Q000145:classification* / Q000235:genetics; D006734:Horse Diseases / Q000453:epidemiology / Q000821:virology*; D006736:Horses; D011247:Pregnancy
keywords: Abortion; EHV-1; Neurological marker; Outbreak