Viruses2026; 18(10); 1125; doi: 10.3390/v18101125

Detection of Shamonda Virus in Two Horses with Neurological Signs in Germany.

Volkwein, ME
·
Köster, J
·
Großmann, E
·
Hafner, N
·
Miller, T
·
Salditt, A
·
Benz, P
·
Beer, M
·
Breithaupt, A
·
Wernike, K

Abstract: Shamonda virus (SHAV), which has recently emerged in Central Europe and has caused disease in numerous cattle herds, was detected in brain tissue from two horses that showed clinical signs, including neurological disorder, and underwent pathological examination. The horses reportedly exhibited seizure-like episodes (Horse A) as well as fever and ataxia (Horse B). In both horses, severe lymphohistiocytic meningoencephalitis with hemorrhages was observed in various parts of the central nervous system (CNS), while outside the CNS no abnormalities were found. The virus genome could be detected by RT-qPCR in all examined parts of the CNS of both horses. In a postmortem cerebrospinal fluid sample of one horse, the virus could only be detected with a very low genome load; however, postmortem contamination cannot be completely ruled out. Consistent with the histological findings, no SHAV genome was detected in either the blood or organs outside the CNS. Postmortem, CNS material-especially brainstem tissue-is suitable for detection of histological lesions and virus genomes via RT-qPCR, while intravital diagnostics of a SHAV infection in horses exhibiting neurological signs is at the moment only possible to a very limited extent. The epidemiological role of horses in the SHAV outbreak is currently unclear.

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Publication Date: 2026-10-10 PubMed ID: 42944045PubMed Central: PMC13709578DOI: 10.3390/v18101125Google Scholar: Lookup

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Summary
Cite This
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Affiliations
MeSH
Conflict of Interest
References
Citations

Journal Article
Case Reports

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

Overview

This study reports the detection of Shamonda virus (SHAV) in two horses from Germany that displayed neurological symptoms.
The investigation included clinical observation, pathological examination, and molecular detection of the virus to understand its role in horse disease.

Background

Shamonda virus is a virus that has recently appeared in Central Europe.
It has primarily been associated with disease outbreaks in cattle herds.
The virus’s effects and presence in horses, particularly those with neurological disorders, are not well understood.

Clinical Presentation

Two horses showed distinct neurological symptoms:
- Horse A exhibited seizure-like episodes.
- Horse B showed signs of fever and ataxia (lack of voluntary coordination of muscle movements).

Pathological Findings

On examination of brain tissue, both horses had severe lymphohistiocytic meningoencephalitis, an inflammation in the brain and surrounding meninges, characterized by:
- Severe inflammation involving immune cells (lymphocytes and histiocytes).
- Presence of hemorrhages (bleeding) in various parts of the central nervous system (CNS).
There were no significant abnormalities found outside the CNS upon pathological examination.

Virological Detection

The virus genome was detected by reverse transcription quantitative PCR (RT-qPCR), a sensitive molecular technique for detecting viral RNA, in all examined parts of the CNS in both horses.
Postmortem cerebrospinal fluid (CSF) from one horse showed very low levels of the virus genome, but possible contamination after death cannot be excluded.
SHAV was not detected in blood or other organs outside the CNS, aligning with the absence of lesions in those tissues.

Diagnostic Implications

Postmortem examination of CNS tissues, especially brainstem samples, is effective for:
- Identifying histological lesions caused by SHAV.
- Detecting the viral genome using RT-qPCR.
Diagnosing SHAV infection in living horses with neurological symptoms remains difficult with current methods.

Epidemiological Considerations

The role of horses in the epidemiology of SHAV outbreaks is currently uncertain.
Unlike cattle, where the virus has caused widespread disease, it is not clear if horses serve as significant hosts or reservoirs for SHAV.

Summary

This study documented neurological disease in horses associated with SHAV infection for the first time in Germany.
It highlights the importance of CNS tissue analysis in detecting SHAV in affected animals and points out challenges in ante-mortem diagnosis.
The findings contribute to understanding the host range of SHAV and raise questions about its broader impact on equine health and epidemiology.

Cite This Article

APA

Volkwein ME, Köster J, Großmann E, Hafner N, Miller T, Salditt A, Benz P, Beer M, Breithaupt A, Wernike K. (2026). Detection of Shamonda Virus in Two Horses with Neurological Signs in Germany. Viruses, 18(10), 1125. https://doi.org/10.3390/v18101125

Publication

Viruses

ISSN: 1999-4915

NlmUniqueID: 101509722

Country: Switzerland

Language: English

Volume: 18

Issue: 10

PII: 1125

Researcher Affiliations

Volkwein, Marielle Elen

Aulendorf State Veterinary Diagnostic Centre, Löwenbreitestraße. 18/20, 88326 Aulendorf, Germany.

Köster, Judith

Aulendorf State Veterinary Diagnostic Centre, Löwenbreitestraße. 18/20, 88326 Aulendorf, Germany.

Großmann, Ernst

Aulendorf State Veterinary Diagnostic Centre, Löwenbreitestraße. 18/20, 88326 Aulendorf, Germany.

Hafner, Nathalie

Animal Disease Fund Baden-Württemberg, Horse Health Service Aulendorf, Talstraße 17, 88326 Aulendorf, Germany.

Miller, Thomas

Aulendorf State Veterinary Diagnostic Centre, Löwenbreitestraße. 18/20, 88326 Aulendorf, Germany.

Salditt, Andreas

Aulendorf State Veterinary Diagnostic Centre, Löwenbreitestraße. 18/20, 88326 Aulendorf, Germany.

Benz, Petra

Aulendorf State Veterinary Diagnostic Centre, Löwenbreitestraße. 18/20, 88326 Aulendorf, Germany.

Beer, Martin

Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Südufer 10, Insel Riems, 17493 Greifswald, Germany.

Breithaupt, Angele

Department of Experimental Animal Facilities and Biorisk Management, Friedrich-Loeffler-Institut, Südufer 10, Insel Riems, 17493 Greifswald, Germany.

Wernike, Kerstin

Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Südufer 10, Insel Riems, 17493 Greifswald, Germany.

MeSH Terms

Animals
Horses
Horse Diseases / virology
Horse Diseases / pathology
Horse Diseases / diagnosis
Germany
Brain / virology
Brain / pathology
Bunyaviridae Infections / veterinary
Bunyaviridae Infections / virology
Bunyaviridae Infections / pathology
Bunyaviridae Infections / diagnosis
Orthobunyavirus / isolation & purification
Orthobunyavirus / genetics
Orthobunyavirus / classification
Nervous System Diseases / veterinary
Nervous System Diseases / virology
Genome, Viral

Conflict of Interest Statement

The authors declare no conflicts of interest.

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