Evaluation of an outbreak of West Nile virus infection in horses: 569 cases (2002).
Abstract: To characterize an outbreak of West Nile virus (WNV) infection in horses in North Dakota in 2002, evaluate vaccine effectiveness, and determine horse characteristics and clinical signs associated with infection. Methods: Retrospective study. Methods: 569 horses. Methods: Data were obtained from veterinary laboratory records, and a questionnaire was mailed to veterinarians of affected horses. Results: Affected horses were defined as horses with typical clinical signs and seroconversion or positive results of virus isolation; affected horses were detected in 52 of the 53 counties and concentrated in the eastern and northeastern regions of the state. Among affected horses, 27% (n = 152) were vaccinated against WNV, 54% (309) were not, and 19% (108) had unknown vaccination status; 61 % (345) recovered, 22% (126) died, and 17% (98) had unknown outcome. The odds of death among nonvaccinated horses were 3 and 16 times the odds among horses that received only 1 or 2 doses of vaccine and horses that were vaccinated according to manufacturer's recommendations, respectively. Horses with recumbency, caudal paresis, and age > 5 years had higher odds of death, whereas horses with incoordination had lower odds of death, compared with affected horses without these characteristics. Conclusions: Vaccination appears to have beneficial effects regarding infection and death caused by WNV.
Publication Date: 2004-11-02 PubMed ID: 15515988DOI: 10.2460/javma.2004.225.1084Google Scholar: Lookup
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- Evaluation Study
- Journal Article
- Research Support
- Non-U.S. Gov't
- Research Support
- U.S. Gov't
- Non-P.H.S.
- Clinical Signs
- Clinical Study
- Diagnosis
- Disease control
- Disease Diagnosis
- Disease Management
- Disease Outbreaks
- Disease Prevention
- Disease Treatment
- Epidemiology
- Equine Health
- Horses
- Infectious Disease
- Mortality
- Public Health
- Retrospective Study
- Vaccination
- Veterinary Care
- Veterinary Medicine
- Veterinary Research
- West Nile Virus
Summary
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This research examines an outbreak of West Nile virus in horses in North Dakota in 2002, looking at the effectiveness of vaccines and the characteristics of the horses that affected the infection.
Methodology
- The researchers employed a retrospective study design to evaluate the 2002 outbreak.
- The sample involved in this study was made up of 569 horses.
- Information was gathered from veterinary laboratory records, with additional data obtained using a questionnaire mailed to the veterinarians responsible for the affected horses.
Results
- The affected horses, identified through clinical signs and seroconversion or positive virus isolation, were found in 52 of the 53 counties in North Dakota.
- These horses were mostly located in the eastern and northeastern regions of the state.
- Horses that had been vaccinated against West Nile virus comprised 27% of the sample, 54% were unvaccinated, and for 19% the vaccination status was unknown.
- Regarding the recovery rate, 61% of the horses recovered from the virus, 22% died, and for 17% the outcome was unknown.
- Non-vaccinated horses were found to have odds of death 3 to 16 times higher than horses who had received one or two doses of the vaccine, and horses who had been vaccinated according to the manufacturer’s recommendations.
- Horses over the age of 5, those exhibiting signs of recumbency, or caudal paresis had higher odds of death, while horses with incoordination were found to have lower odds of death compared to affected horses not manifesting these characteristics.
Conclusions
- The study concluded that vaccination seemed to offer significant protection against both infection and death from West Nile virus.
Cite This Article
APA
Schuler LA, Khaitsa ML, Dyer NW, Stoltenow CL.
(2004).
Evaluation of an outbreak of West Nile virus infection in horses: 569 cases (2002).
J Am Vet Med Assoc, 225(7), 1084-1089.
https://doi.org/10.2460/javma.2004.225.1084 Publication
Researcher Affiliations
- North Dakota State Board of Animal Health, 600 E Boulevard Ave, Dept 602, Bismarck, ND 58505-0020, USA.
MeSH Terms
- Animals
- Disease Outbreaks / veterinary
- Female
- Horse Diseases / epidemiology
- Horse Diseases / mortality
- Horse Diseases / prevention & control
- Horses
- Male
- North Dakota / epidemiology
- Retrospective Studies
- Survival Analysis
- Vaccination / veterinary
- Viral Vaccines / administration & dosage
- West Nile Fever / epidemiology
- West Nile Fever / mortality
- West Nile Fever / prevention & control
- West Nile Fever / veterinary
- West Nile virus / immunology
Citations
This article has been cited 20 times.- DeNotta S, McFarlane D. Immunosenescence and inflammaging in the aged horse. Immun Ageing 2023 Jan 6;20(1):2.
- Cavalleri JV, Korbacska-Kutasi O, Leblond A, Paillot R, Pusterla N, Steinmann E, Tomlinson J. European College of Equine Internal Medicine consensus statement on equine flaviviridae infections in Europe. J Vet Intern Med 2022 Nov;36(6):1858-1871.
- Ganzenberg S, Sieg M, Ziegler U, Pfeffer M, Vahlenkamp TW, Hörügel U, Groschup MH, Lohmann KL. Seroprevalence and Risk Factors for Equine West Nile Virus Infections in Eastern Germany, 2020. Viruses 2022 May 30;14(6).
- Bergmann F, Trachsel DS, Stoeckle SD, Bernis Sierra J, Lübke S, Groschup MH, Gehlen H, Ziegler U. Seroepidemiological Survey of West Nile Virus Infections in Horses from Berlin/Brandenburg and North Rhine-Westphalia, Germany. Viruses 2022 Jan 25;14(2).
- Selim A, Megahed A, Kandeel S, Alouffi A, Almutairi MM. West Nile virus seroprevalence and associated risk factors among horses in Egypt. Sci Rep 2021 Oct 22;11(1):20932.
- Levasseur A, Arsenault J, Paré J. Surveillance of West Nile virus in horses in Canada: A retrospective study of cases reported to the Canadian Food Inspection Agency from 2003 to 2019. Can Vet J 2021 May;62(5):469-476.
- Kaiser JA, Barrett ADT. Twenty Years of Progress Toward West Nile Virus Vaccine Development. Viruses 2019 Sep 5;11(9).
- Trumpp KM, Parsley AL, Lewis MJ, Camp JW Jr, Taylor SD. Presumptive tick paralysis in 2 American Miniature horses in the United States. J Vet Intern Med 2019 Jul;33(4):1784-1788.
- Kumar B, Manuja A, Gulati BR, Virmani N, Tripathi BN. Zoonotic Viral Diseases of Equines and Their Impact on Human and Animal Health. Open Virol J 2018;12:80-98.
- Ahlers LRH, Goodman AG. The Immune Responses of the Animal Hosts of West Nile Virus: A Comparison of Insects, Birds, and Mammals. Front Cell Infect Microbiol 2018;8:96.
- Angenvoort J, Brault AC, Bowen RA, Groschup MH. West Nile viral infection of equids. Vet Microbiol 2013 Nov 29;167(1-2):168-80.
- Iyer AV, Kousoulas KG. A review of vaccine approaches for West Nile virus. Int J Environ Res Public Health 2013 Sep 10;10(9):4200-23.
- Venter M, Human S, Zaayman D, Gerdes GH, Williams J, Steyl J, Leman PA, Paweska JT, Setzkorn H, Rous G, Murray S, Parker R, Donnellan C, Swanepoel R. Lineage 2 west nile virus as cause of fatal neurologic disease in horses, South Africa. Emerg Infect Dis 2009 Jun;15(6):877-84.
- Ndiva Mongoh M, Hearne R, Dyer NW, Khaitsa ML. The economic impact of West Nile virus infection in horses in the North Dakota equine industry in 2002. Trop Anim Health Prod 2008 Jan;40(1):69-76.
- Shrestha B, Ng T, Chu HJ, Noll M, Diamond MS. The relative contribution of antibody and CD8+ T cells to vaccine immunity against West Nile encephalitis virus. Vaccine 2008 Apr 7;26(16):2020-33.
- Epp T, Waldner C, West K, Townsend H. Factors associated with West Nile virus disease fatalities in horses. Can Vet J 2007 Nov;48(11):1137-45.
- Seino KK, Long MT, Gibbs EP, Bowen RA, Beachboard SE, Humphrey PP, Dixon MA, Bourgeois MA. Comparative efficacies of three commercially available vaccines against West Nile Virus (WNV) in a short-duration challenge trial involving an equine WNV encephalitis model. Clin Vaccine Immunol 2007 Nov;14(11):1465-71.
- Mongoh MN, Khaitsa ML, Dyer NW. Environmental and ecological determinants of West Nile virus occurrence in horses in North Dakota, 2002. Epidemiol Infect 2007 Jan;135(1):57-66.
- Naveed A, Eertink LG, Wang D, Li F. Lessons Learned from West Nile Virus Infection:Vaccinations in Equines and Their Implications for One Health Approaches. Viruses 2024 May 14;16(5).
- Schwarz ER, Long MT. Comparison of West Nile Virus Disease in Humans and Horses: Exploiting Similarities for Enhancing Syndromic Surveillance. Viruses 2023 May 24;15(6).
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