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Home / Equine Research Bank / Viruses / Epidemiological Aspects of Equid Herpesvirus-Associated Myel...
Viruses2022; 14(11); 2576; doi: 10.3390/v14112576

Epidemiological Aspects of Equid Herpesvirus-Associated Myeloencephalopathy (EHM) Outbreaks.

Abstract: Equid Herpesvirus Myeloencephalopathy (EHM) is a multifactorial disease following an EHV-1 infection in Equidae. We investigated a total of 589 horses on 13 premises in Europe in search of risk factors for the development of EHM. We found that fever ( < 0.001), increasing age ( = 0.032), and female sex ( = 0.042) were risk factors for EHM in a logistic mixed model. Some breeds had a decreased risk to develop EHM compared to others (Shetland and Welsh ponies; = 0.017; = 0.031), and fewer EHV-1-vaccinated horses were affected by EHM compared to unvaccinated horses ( = 0.02). Data evaluation was complex due to high variability between outbreaks with regards to construction and environment; viral characteristics and the virus's transmissibility were affected by operational management. This study confirms earlier suspected host-specific risk factors, and our data support the benefit of high vaccine coverage at high-traffic boarding facilities.
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Publication Date: 2022-11-21 PubMed ID: 36423188PubMed Central: PMC9695031DOI: 10.3390/v14112576Google Scholar: Lookup
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  • Journal Article
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  • Non-U.S. Gov't

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 investigated risk factors for Equid Herpesvirus Myeloencephalopathy (EHM), a disease in horses, in an European context. They found fever, older age, female sex, and certain breeds to increase the risk, while vaccination seems to have a protective effect, and highlighted the variability of outbreaks due to different environmental and management factors.

Introduction to the Study

  • The study focuses on Equid Herpesvirus Myeloencephalopathy (EHM), a disease that affects members of the Equidae family (including horses) and is associated with the Equid Herpesvirus-1 (EHV-1) infection.
  • The researchers aimed to investigate potential risk factors that could contribute to the development of EHM by examining a large sample—589 horses across 13 premises in Europe.

Findings and Results

  • The results indicated that fever, increasing age, and female sex were significant risk factors for EHM. In other words, horses that had a fever, were older, or were female, had higher chances of developing EHM.
  • Interestingly, the study found a different level of susceptibility among different horse breeds – specifically, Shetland and Welsh ponies were found to have a decreased risk of developing EHM compared to other breeds.
  • The research also highlighted the protective effect of EHV-1 vaccination since fewer vaccinated horses developed EHM than their unvaccinated counterparts.
  • However, the interpretation of data was complicated due to the high variability between different outbreaks. This variability was linked to factors such as the construction and environment of the premises, characteristics of the virus, and how the premises were managed operationally.

Conclusion and Implications

  • This study not only confirmed some of the previously suspected risk factors associated with EHM but also provided new evidence supporting the benefit of EHV-1 vaccination.
  • Specifically, the findings suggest that implementing high vaccine coverage in high-traffic boarding facilities could significantly help in controlling EHM epidemics.
  • The study also underscores the need for further research to better understand the multifactorial nature of EHM, as well as the influence of different environmental and management factors on the disease’s spread and severity.

Cite This Article

APA
Klouth E, Zablotski Y, Petersen JL, de Bruijn M, Gröndahl G, Müller S, Goehring LS. (2022). Epidemiological Aspects of Equid Herpesvirus-Associated Myeloencephalopathy (EHM) Outbreaks. Viruses, 14(11), 2576. https://doi.org/10.3390/v14112576

Publication

Viruses
ISSN: 1999-4915
NlmUniqueID: 101509722
Country: Switzerland
Language: English
Volume: 14
Issue: 11
PII: 2576

Researcher Affiliations

Klouth, Eva
  • Center for Clinical Veterinary Medicine, Faculty of Veterinary Medicine, Ludwig-Maximilians University, 80539 Munich, Germany.
Zablotski, Yury
  • Center for Clinical Veterinary Medicine, Faculty of Veterinary Medicine, Ludwig-Maximilians University, 80539 Munich, Germany.
Petersen, Jessica L
  • Department of Animal Science, University of Nebraska, Lincoln, NE 68588, USA.
de Bruijn, Marco
  • Wolvega Equine Hospital, 8474 EA Oldeholtpade, The Netherlands.
Gröndahl, Gittan
  • National Veterinary Institute (SVE), 75189 Uppsala, Sweden.
Müller, Susanne
  • Baden-Wuerttemberg Animal Health Services, 70736 Fellbach, Germany.
Goehring, Lutz S
  • M.H. Gluck Equine Research Center, College of Agriculture, Food and the Environment, University of Kentucky, Lexington, KY 40506, USA.

MeSH Terms

  • Horses
  • Female
  • Animals
  • Herpesviridae Infections / epidemiology
  • Herpesviridae Infections / veterinary
  • Horse Diseases / epidemiology
  • Herpesvirus 1, Equid
  • Disease Outbreaks / veterinary
  • Risk Factors

Conflict of Interest Statement

The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

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Citations

This article has been cited 8 times.
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