Humoral response to West Nile virus vaccination in alpacas and llamas.
Abstract: To determine humoral responses to an equine West Nile virus (WNV) vaccine in healthy alpacas and llamas and compare responses in alpacas and llamas with responses in horses. Methods: Clinical trial. Methods: 28 alpacas, 56 llamas, and 16 horses. Methods: Horses received 2 vaccinations at 4-week intervals, and alpacas and llamas received 3 vaccinations at 3-week intervals. Fifty-five llamas received a fourth vaccination 3 weeks after the third. Blood samples were collected immediately prior to each vaccination, 3 weeks after the last vaccination for alpacas and llamas, and 4 weeks after the last vaccination for horses and tested for virus-neutralizing antibodies. Samples from 29 randomly selected vaccinated llamas were used. Results: None of the animals developed any local or systemic adverse reactions. Four of 28 (14%) alpacas, 4 of 29 (14%) llamas, and 7 of 16 (44%) horses were seropositive 3 (llamas and alpacas) or 4 (horses) weeks after administration of the first vaccination; 27 of 28 (96%) alpacas, 26 of 29 (90%) llamas, and 15 of 16 (94%) horses were seropositive after administration of the second vaccination; and all 28 alpacas and 28 of 29 (97%) llamas were seropositive 3 weeks after administration of the third vaccination. Conclusions: Results suggest that vaccination with the equine WNV vaccine is safe in alpacas and llamas. Administration of 3 vaccinations generally resulted in virus-neutralizing antibody titers similar to those observed following 2 vaccinations in horses; however, because it is not known what antibody titer would be protective against clinical WNV disease in alpacas or llamas, we cannot conclude that the vaccine was efficacious.
Publication Date: 2004-08-27 PubMed ID: 15328718DOI: 10.2460/javma.2004.225.414Google Scholar: Lookup
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- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
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This research observed the responses of alpacas, llamas, and horses to a West Nile virus (WNV) vaccine designed for equines. The study determined that the vaccine elicited the production of virus-neutralizing antibodies in the majority of participants without causing any noticeable adverse reactions.
Vaccination Schedule and Sample Collection
- The animals followed different vaccination schedules: horses received two vaccinations four weeks apart, while alpacas and llamas received three vaccinations three weeks apart, with a subgroup of llamas treated to a fourth.
- The vaccinations were administered to healthy animals: 28 alpacas, 56 llamas, and 16 horses.
- Blood samples were collected immediately prior to each vaccination, three weeks after the last vaccination for alpacas and llamas, and four weeks after the last vaccination for horses. These samples were tested for antibody titers, the concentration of antibodies in the blood.
Results of Vaccination
- No adverse reactions were reported in any of the animals after the vaccination.
- Initially, only 14% of alpacas and llamas and 44% of horses were found to have virus-neutralizing antibodies three or four weeks after the first vaccination.
- However, following the second vaccination, the seropositive rates increased dramatically to 96% in alpacas, 90% in llamas, and 94% in horses.
- Following a third vaccination, all alpacas and an almost perfect proportion of llamas (97%) were found to be seropositive.
Conclusion and Future Research
- The research points toward the equine WNV vaccine being safe for use in alpacas and llamas, as it induced a robust virus-neutralizing antibody response.
- However, the researchers qualified their findings, stating that they couldn’t definitively conclude the vaccine’s efficacy, since the protective antibody titer against WNV in alpacas and llamas is not currently known.
- The study results, thus, show the need for further research to establish the protective antibody titer levels in alpacas and llamas against WNV and to further assess the vaccine’s protective efficacy in these species.
Cite This Article
APA
Kutzler MA, Baker RJ, Mattson DE.
(2004).
Humoral response to West Nile virus vaccination in alpacas and llamas.
J Am Vet Med Assoc, 225(3), 414-416.
https://doi.org/10.2460/javma.2004.225.414 Publication
Researcher Affiliations
- Department of Clinical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331, USA.
MeSH Terms
- Animals
- Antibodies, Viral / biosynthesis
- Antibodies, Viral / blood
- Camelids, New World / immunology
- Camelids, New World / virology
- Female
- Horse Diseases / immunology
- Horse Diseases / prevention & control
- Horses
- Male
- Neutralization Tests / veterinary
- Random Allocation
- Safety
- Time Factors
- Vaccination / veterinary
- Vaccines, Inactivated / administration & dosage
- Viral Vaccines / administration & dosage
- Viral Vaccines / immunology
- West Nile Fever / immunology
- West Nile Fever / prevention & control
- West Nile Fever / veterinary
- West Nile virus / immunology
Citations
This article has been cited 9 times.- Arfuso F, Giudice E, Di Pietro S, Piccione G, Giannetto C. Modulation of Serum Protein Electrophoretic Pattern and Leukocyte Population in Horses Vaccinated against West Nile Virus. Animals (Basel) 2021 Feb 11;11(2).
- Yeh JY, Chung KM, Song J. Differentiation of West Nile virus-infected animals from vaccinated animals by competitive ELISA using monoclonal antibodies against non-structural protein 1. Vector Borne Zoonotic Dis 2012 May;12(5):380-7.
- Daley LP, Kutzler MA, Bennett BW, Smith MC, Glaser AL, Appleton JA. Effector functions of camelid heavy-chain antibodies in immunity to West Nile virus. Clin Vaccine Immunol 2010 Feb;17(2):239-46.
- Kapil S, Yeary T, Evermann JF. Viral diseases of new world camelids. Vet Clin North Am Food Anim Pract 2009 Jul;25(2):323-37.
- Jones M, Boileau M. Camelid herd health. Vet Clin North Am Food Anim Pract 2009 Jul;25(2):239-63.
- Brault AC. Changing patterns of West Nile virus transmission: altered vector competence and host susceptibility. Vet Res 2009 Mar-Apr;40(2):43.
- Rao S, Kong WP, Wei CJ, Yang ZY, Nason M, Styles D, DeTolla LJ, Panda A, Sorrell EM, Song H, Wan H, Ramirez-Nieto GC, Perez D, Nabel GJ. Multivalent HA DNA vaccination protects against highly pathogenic H5N1 avian influenza infection in chickens and mice. PLoS One 2008;3(6):e2432.
- Magnarelli LA, Bushmich SL, Anderson JF, Ledizet M, Koski RA. Serum antibodies to West Nile virus in naturally exposed and vaccinated horses. J Med Microbiol 2008 Sep;57(Pt 9):1087-1093.
- Najafi S, Jojani M, Najafi K, Costanzo V, Vicidomini C, Roviello GN. West Nile Virus: Epidemiology, Surveillance, and Prophylaxis with a Comparative Insight from Italy and Iran. Vaccines (Basel) 2026 Jan 3;14(1).
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