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Home / Equine Research Bank / J Am Vet Med Assoc / Outcome of equids with clinical signs of West Nile virus inf...
Journal of the American Veterinary Medical Association2004; 225(2); 267-274; doi: 10.2460/javma.2004.225.267

Outcome of equids with clinical signs of West Nile virus infection and factors associated with death.

Abstract: To determine outcome of equids in the western United States with clinical signs of West Nile virus (WNV) infection and identify factors associated with risk of death in infected equids. Methods: Cross-sectional study. Methods: 484 equids in Nebraska and Colorado. Methods: Owners of 484 equids with laboratory-confirmed West Nile virus infection in Nebraska and Colorado were contacted by telephone, and a questionnaire was used to obtain information on signalment, management, clinical signs, date of disease onset, duration of disease, WNV vaccination status, and health status at the time of the interview. Results: 137 of 482 (28.4%) animals died or were euthanatized. Ataxia, lethargy, muscle fasciculations, and weakness were the most common clinical signs of disease. Animals > or = 3 years old were more likely to die than were animals < or = 2 years old. Unvaccinated equids were twice as likely to die as were animals that had been vaccinated at least once prior to the onset of disease. Animals that were recumbent and unable to rise were 78 times as likely to die as were animals that never lost the ability to rise. Females were 2.9 times as likely to die as males. Two hundred seventy-one of 339 (79.9%) animals that survived recovered fully; mean duration of disease for these animals was 22.3 days. Conclusions: Among equids with WNV infection, age, vaccination status, an inability to rise, and sex were associated with the risk of death.
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Publication Date: 2004-08-25 PubMed ID: 15323385DOI: 10.2460/javma.2004.225.267Google Scholar: Lookup
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  • Journal Article
  • Research Support
  • Non-U.S. Gov't
  • Research Support
  • U.S. Gov't
  • Non-P.H.S.

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 focuses on studying how West Nile virus (WNV) infection impacts the survival of equids (horses, donkeys, etc.) in the western United States and identifying the factors that increase the risk of death due to the disease. It revealed that factors such as the infected animal’s age, vaccination status, ability to rise, and sex influence the likelihood of fatality.

Research Methodology

  • The research was designed as a cross-sectional study involving 484 equids from Nebraska and Colorado.
  • These animals were identified as having laboratory-confirmed West Nile virus infection.
  • The researchers contacted the owners of these animals via telephone and used a questionnaire to gather information related to the animals’ health status, management, clinical signs, date of disease onset, duration of disease, and WNV vaccination status.

Major Findings

  • Out of the total equids in the study, 28.4% (137 of 482) either died or had to be euthanized due to the severity of their condition.
  • The most common clinical signs of the disease observed were ataxia, lethargy, muscle fasciculations, and weakness.
  • Older equids (age three years or above) had a higher likelihood of death in comparison to younger ones (two years old or less).
  • The equids that had not been vaccinated were twice as likely to die compared to the vaccinated ones.
  • Animals that were recumbent and unable to rise were 78 times more likely to die than those who retained the ability to rise.
  • Female equids were found to be 2.9 times more likely to die due to WNV infection compared to males.
  • For the survivors, around 80% (271 out of 339) fully recovered from the disease, with an average recovery time of 22.3 days.

Conclusion

  • The research concluded that factors such as age, vaccination status, inability to rise, and sex played a critical role in influencing the risk of death among equids with West Nile virus infection.

Cite This Article

APA
Salazar P, Traub-Dargatz JL, Morley PS, Wilmot DD, Steffen DJ, Cunningham WE, Salman MD. (2004). Outcome of equids with clinical signs of West Nile virus infection and factors associated with death. J Am Vet Med Assoc, 225(2), 267-274. https://doi.org/10.2460/javma.2004.225.267

Publication

Journal of the American Veterinary Medical Association
ISSN: 0003-1488
NlmUniqueID: 7503067
Country: United States
Language: English
Volume: 225
Issue: 2
Pages: 267-274

Researcher Affiliations

Salazar, Patricia
  • Animal Population Health Institute, Colorado State University, Fort Collins, CO 80523, USA.
Traub-Dargatz, Josie L
    Morley, Paul S
      Wilmot, Delwin D
        Steffen, David J
          Cunningham, Wayne E
            Salman, M D

              MeSH Terms

              • Age Factors
              • Animal Husbandry / methods
              • Animals
              • Anti-Inflammatory Agents, Non-Steroidal / therapeutic use
              • Antiviral Agents / therapeutic use
              • Colorado / epidemiology
              • Cross-Sectional Studies
              • Female
              • Horse Diseases / drug therapy
              • Horse Diseases / mortality
              • Horses
              • Logistic Models
              • Male
              • Nebraska / epidemiology
              • Risk Factors
              • Sex Factors
              • Survival Analysis
              • Treatment Outcome
              • Vaccination / statistics & numerical data
              • Vaccination / veterinary
              • West Nile Fever / drug therapy
              • West Nile Fever / mortality
              • West Nile Fever / veterinary
              • West Nile virus / pathogenicity

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