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Animals : an open access journal from MDPI2022; 12(3); doi: 10.3390/ani12030337

Equine Encephalosis Virus.

Abstract: Equine encephalosis (EE) is an arthropod-borne, noncontagious, febrile disease of horses. It is caused by EE virus (EEV), an Orbivirus of the Reoviridae family transmitted by Culicoides. Within the EEV serogroup, seven serotypes (EEV-1-7) have been identified to date. This virus was first isolated from a horse in South Africa in 1967 and until 2008 was believed to be restricted to southern Africa. In 2008-2009, isolation of EEV in an outbreak reported from Israel demonstrated the emergence of this pathogen into new niches. Indeed, testing in retrospect sera samples revealed that EEV had already been circulating outside of South Africa since 2001. Although EEV normally does not cause severe clinical disease, it should be considered important since it may indicate the possible spread of other related, much more pathogenic viruses, such as African horse sickness virus (AHSV). The spread of EEV from South Africa to central Africa, the Middle East and India is an example of the possible emergence of new pathogens in new niches, as was seen in the case of West Nile virus, and should be a reminder not to limit the differential list when facing a possible outbreak or a cluster of clinical cases. This review summarizes current knowledge regarding EEV structure, pathogenesis, clinical significance, and epidemiology.
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Publication Date: 2022-01-29 PubMed ID: 35158658PubMed Central: PMC8833465DOI: 10.3390/ani12030337Google Scholar: Lookup
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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.

This research discusses the discovery, spread, and potential implications of the Equine Encephalosis Virus (EEV), a viral disease transmitted by ticks predominantly affecting horses, which has been found to exist beyond its initial detection in South Africa.

Objective and Overview

The research primarily focuses on the study of the Equine Encephalosis Virus (EEV), a febrile disease borne by arthropods like ticks and affecting horses predominantly. Through a comprehensive review, the paper details the EEV structure, causes, clinical significance, and its geographical spread across the globe, with a detail on its implications on global health status.

Characteristics of EEV

  • Equine Encephalosis (EE), the disease caused by EEV, is noncontagious and leads to fever in infected horses.
  • The virus is a member of the Reoviridae family.
  • Within the EEV serogroup, seven distinct serotypes (EEV-1-7) have been identified.

History and Geographical Spread of EEV

  • EEV was first isolated from a horse in South Africa in 1967.
  • It was initially thought to be contained within southern Africa until 2008, when an outbreak occurred in Israel, signifying the spread of the virus to new regions.
  • Retroactive testing of sera samples suggest that EEV had already been present outside of South Africa since 2001.
  • The virus has since spread to Central Africa, the Middle East, and India.

Importance and Future Implications

  • While EEV doesn’t usually cause severe disease, its presence outside its initial geographical region is notable. This is indicative of possible traces of other more pathogenic virus-like the African horse sickness virus (AHSV).
  • The global spread of EEV serves as a cautionary tale for how rapidly and unexpectedly new pathogens can emerge in new niches, impacting global health security.
  • It prompts the need for an expanded differential list when diagnosing potential outbreaks or clinical case clusters.

Cite This Article

APA
Tirosh-Levy S, Steinman A. (2022). Equine Encephalosis Virus. Animals (Basel), 12(3). https://doi.org/10.3390/ani12030337

Publication

Animals : an open access journal from MDPI
ISSN: 2076-2615
NlmUniqueID: 101635614
Country: Switzerland
Language: English
Volume: 12
Issue: 3

Researcher Affiliations

Tirosh-Levy, Sharon
  • Koret School of Veterinary Medicine, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 7610001, Israel.
  • Division of Parasitology, Kimron Veterinary Institute, Beit Dagan 50200, Israel.
Steinman, Amir
  • Koret School of Veterinary Medicine, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 7610001, Israel.

Conflict of Interest Statement

The authors declare no conflict of interest.

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Citations

This article has been cited 2 times.
  1. Piketh G, Viljoen A, Eberhardt C. Clinical signs, clinical pathology and outcomes in horses infected naturally with equine encephalosis virus. Equine Vet J 2026 Mar;58(2):434-443.
    doi: 10.1111/evj.70117pubmed: 41235818google scholar: lookup
  2. Steinman A, Erster O, Tirosh-Levy S. Virus Infection in Equine. Animals (Basel) 2022 Apr 8;12(8).
    doi: 10.3390/ani12080957pubmed: 35454204google scholar: lookup
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