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Journal of veterinary internal medicine2013; 27(2); 339-346; doi: 10.1111/jvim.12051

Case-control study of a multistate equine herpesvirus myeloencephalopathy outbreak.

Abstract: A large multistate outbreak of equine herpesvirus myeloencephalopathy (EHM) occurred in May 2011 among horses that participated in a competitive event. Objective: To identify EHM risk factors among horses with a common exposure venue. Methods: A total of 123 horses: 19 horses with EHM, 14 equine herpesvirus-1 cases with no reported neurologic signs, and 90 control horses. Methods: EHM case survey data were compared with data from EHV-1 cases with no neurologic signs and healthy controls using univariable and multivariable methods. Results: Significant factors associated with higher risk for EHM compared with EHV-1 cases with no neurologic signs were (1) greater number of biosecurity risks at the event, (2) female sex, (3) increasing number of classes competed in at the event, and (4) an interaction between sex and number of classes competed in. In the EHM versus controls comparison, in addition to sex and biosecurity risks, factors associated with higher EHM risk included EHV-1 vaccination in the 5 weeks before the event and increasing number of events attended in April 2011; zinc dietary supplementation was associated with decreased risk. An interaction between sex and the number of events attended in April 2011 also was significant. Conclusions: Findings from this study suggest that dietary zinc supplementation may be associated with decreased risk of EHM. Several factors were associated with increased risk of EHM. Additional investigations of factors associated with risk of EHM are warranted to evaluate the importance of these factors in this complex disease of horses.
Copyright © 2013 by the American College of Veterinary Internal Medicine.
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Publication Date: 2013-02-07 PubMed ID: 23398291DOI: 10.1111/jvim.12051Google 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.

The research is about a case-control study conducted on a large multistate outbreak of equine herpesvirus myeloencephalopathy (EHM) that occurred in May 2011 among horses that participated in a competitive event. Their prime objective was to identify the risk factors of EHM among these horses.

Research Methodology

  • The researchers selected a total of 123 horses divided into three categories: 19 horses with EHM, 14 equine herpesvirus-1 cases with no reported neurologic signs, and 90 control horses.
  • Using univariable and multivariable methods, they then compared the EHM case survey data with those of the EHV-1 cases and the controls.

Results

  • From the comparative study, certain factors were found to be significantly associated with higher risk for EHM compared to EHV-1 cases with no neurologic signs. These are (1) greater number of biosecurity risks at the event, (2) female sex, (3) increasing number of classes competed in at the event, and (4) an interaction between sex and number of classes competed in.
  • In the comparison between EHM and healthy controls, the factors associated with higher EHM risk went beyond sex and biosecurity risks. These included EHV-1 vaccination in the 5 weeks before the event and an increasing number of events attended in April 2011. However, dietary supplementation with zinc was associated with a decreased risk.
  • A significant interaction was also observed between the sex of the horse and the number of events attended in April 2011.

Conclusions

  • The study suggests that dietary zinc supplementation may be associated with a decreased risk of EHM.
  • Several other factors were found to increase the risk of EHM.
  • The researchers recommend further investigations to evaluate the importance of these risk factors in this complex horse disease.

Cite This Article

APA
Traub-Dargatz JL, Pelzel-McCluskey AM, Creekmore LH, Geiser-Novotny S, Kasari TR, Wiedenheft AM, Bush EJ, Bjork KE. (2013). Case-control study of a multistate equine herpesvirus myeloencephalopathy outbreak. J Vet Intern Med, 27(2), 339-346. https://doi.org/10.1111/jvim.12051

Publication

Journal of veterinary internal medicine
ISSN: 1939-1676
NlmUniqueID: 8708660
Country: United States
Language: English
Volume: 27
Issue: 2
Pages: 339-346

Researcher Affiliations

Traub-Dargatz, J L
  • Colorado State University College of Veterinary Medicine and Biomedical Sciences, Animal Population Health Institute (APHI), Fort Collins, CO 80523, USA. jtraub1@lamar.colostate.edu
Pelzel-McCluskey, A M
    Creekmore, L H
      Geiser-Novotny, S
        Kasari, T R
          Wiedenheft, A M
            Bush, E J
              Bjork, K E

                MeSH Terms

                • Animals
                • Case-Control Studies
                • Disease Outbreaks / veterinary
                • Encephalomyelitis / epidemiology
                • Encephalomyelitis / veterinary
                • Encephalomyelitis / virology
                • Female
                • Herpesviridae Infections / epidemiology
                • Herpesviridae Infections / veterinary
                • Herpesviridae Infections / virology
                • Herpesvirus 1, Equid / isolation & purification
                • Horse Diseases / epidemiology
                • Horse Diseases / virology
                • Horses
                • Male
                • Multivariate Analysis
                • Risk Factors
                • Surveys and Questionnaires
                • United States / epidemiology

                Citations

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