First report of equine parvovirus‐hepatitis‐associated Theiler's disease in Europe. (25th March 2020)

• Record Type: Journal Article
• Authors: Vengust, Modest; Jager, Mason C.; Zalig, Valentina; Cociancich, Vasilij; Laverack, Melissa; Renshaw, Randall W.; Dubovi, Edward; Tomlinson, Joy E.; Van de Walle, Gerlinde R.; Divers, Thomas J.
• Is Part Of: Equine veterinary journal. Volume 52:Number 6(2020)
• Page Start: 841
• Page End: 847
• Publication Date: 2020-03-25
• Subjects: Copiparvovirus -- equine parvovirus -- horse -- in situ hybridisation -- liver -- serum hepatitis; Horses -- Diseases -- Periodicals; 636.108905
• DOI: 10.1111/evj.13254
• Languages: English
• ISSNs: 0425-1644

Abstract

Abstract: Background: Equine parvovirus‐hepatitis (EqPV‐H) has been proposed as the aetiological cause of Theiler's disease, also known as serum hepatitis. EqPV‐H‐associated Theiler's disease has not been previously reported in Europe. Objectives: To determine whether EqPV‐H infection was associated with a 2018‐2019 outbreak of Theiler's disease in four horses on a studfarm. Study design: Descriptive case series. Methods: The medical records of four horses from the same farm diagnosed with fatal Theiler's disease were examined retrospectively. Information collected included a clinical history, physical examination findings, tetanus antitoxin exposure, serum biochemistry and necropsy reports. Liver tissue from all four horses was tested for EqPV‐H using PCR and in situ hybridisation (ISH) assays. Results: Three of the horses had a history of recent (7‐11 weeks) tetanus antitoxin administration. Liver tissue from all four horses tested positive for EqPV‐H with PCR. In situ hybridisation revealed a widespread distribution of viral nucleic acid in hepatocytes in one case, and a more sporadic distribution in the remaining three cases. Main limitations: Case controls were not available from the farm in question given the retrospective nature of analysis. Conclusions: This case series documents the first reported EqPV‐H‐associated Theiler's disease in Europe and the first use of ISH to visualise the viral nucleic acid in liver tissues of horses with Theiler's disease.