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Equine veterinary journal2022; 55(3); 389-404; doi: 10.1111/evj.13870

Efficacy of vaccination against equine herpesvirus type 1 (EHV-1) infection: Systematic review and meta-analysis of randomised controlled challenge trials.

Abstract: Equid herpesvirus type 1 (EHV-1) infection can cause a range of disease syndromes of variable severity that can result in a lethal outcome and restriction of horse movements, especially in the case of outbreaks involving neurological disease. Vaccination is one of the tools used to control the infection. It is widely known that vaccination is not completely effective in ensuring protection against disease caused by this virus. In fact, the real efficacy of vaccination against EHV-1 related disease has not been measured and no systematic reviews exist on this topic. Objective: To perform a systematic review and meta-analysis on the efficacy of commercial or candidate vaccines against EHV-1 in randomised controlled trials (RCT) all of which involved experimental challenge of the test subjects. Methods: Systematic review and meta-analysis. Methods: RCTs were searched using the search algorithm (([equid herpesvirus* OR equine herpesvirus* OR EHV-1]) AND vaccin*) AND (trial OR experimental OR challenge) on PubMed, Science Citation Index Expanded, Scopus, and CAB Abstracts. Where appropriate, meta-analysis was performed using RevMan 5.4. Results: Eight studies were selected and were analysed for their respective characteristics and possible shortcomings. The results of RCTs revealed that there was a general improvement in the clinical and virological outcomes of EHV-1 infection following vaccination, but that the effects were very slight. The reduced beneficial effect is probably amplified by the paucity of detailed data reported in the studies that did not allow for the comparison of parameters in many of the cases analysed. Conclusions: The remarkable heterogeneity and the poor quality of reporting of the selected studies. Conclusions: Meta-analysis has shown that EHV-1 vaccination generally results in a slight improvement in clinical and virological outcomes, although not to a significant extent. The cumulative results have probably been affected by the lack of information on some parameters not systematically reported in the studies. An improvement in the standard of reporting and better standardisation of the data collected would likely have improved the quality of each study and enabled more effective comparison of the studies with each other.
© 2022 The Authors. Equine Veterinary Journal published by John Wiley & Sons Ltd on behalf of EVJ Ltd.
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Publication Date: 2022-08-31 PubMed ID: 35946376DOI: 10.1111/evj.13870Google Scholar: Lookup
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  • Meta-Analysis
  • Systematic Review
  • Journal Article
  • Review

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 article explores the effectiveness of vaccines in controlling the Equid herpesvirus type 1 (EHV-1) infection in horses. It involves a systematic review and meta-analysis of randomised controlled trials, revealing that while some improvement is seen after vaccination, the effects are minimal.

Research Objective

This meta-analysis sought to measure the real efficacy of commercial or candidate vaccines against EHV-1 through a systematic review of randomized controlled trials (RCTs). All the RCTs involved experimental challenges to the test subjects.

Methodology

The researchers used a systematic review and meta-analysis method to ascertain the efficacy of vaccines against EHV-1.

  • RCTs were researched using a search algorithm that included various iterations of equine herpesvirus and vaccination terms.
  • The search was done in multiple sources, namely PubMed, Science Citation Index Expanded, Scopus, and CAB Abstracts.
  • The researchers then performed a meta-analysis on the gathered data using RevMan 5.4 software.

Findings

On analyzing the gathered data:

  • Eight studies were selected and analyzed for their characteristics and possible shortcomings.
  • It was found that there was a slight overall improvement in the clinical and virological outcomes of EHV-1 infection after vaccination.
  • However, the study also points out that the beneficial effects were limited and that the scarcity of detailed data in the studies possibly amplified this reduced effect.

Conclusion

The study concludes:

  • Despite some heterogeneity and the poor quality of reporting, the meta-analysis suggests that EHV-1 vaccination results in only a minor improvement in clinical and virological outcomes.
  • The lack of systematically reported parameters in the studies probably affected the cumulative results.
  • There’s a call for an improvement in reporting standards and better standardization of collected data, which would heighten the study quality and enable more effective comparisons.

Cite This Article

APA
Marenzoni ML, De Waure C, Timoney PJ. (2022). Efficacy of vaccination against equine herpesvirus type 1 (EHV-1) infection: Systematic review and meta-analysis of randomised controlled challenge trials. Equine Vet J, 55(3), 389-404. https://doi.org/10.1111/evj.13870

Publication

Equine veterinary journal
ISSN: 2042-3306
NlmUniqueID: 0173320
Country: United States
Language: English
Volume: 55
Issue: 3
Pages: 389-404

Researcher Affiliations

Marenzoni, Maria Luisa
  • Department of Veterinary Medicine, University of Perugia, Perugia, Italy.
De Waure, Chiara
  • Department of Medicine and Surgery, University of Perugia, Perugia, Italy.
Timoney, Peter J
  • Department of Veterinary Science, Maxwell H. Gluck Equine Research Center, Lexington, Kentucky, USA.

MeSH Terms

  • Animals
  • Horses
  • Herpesvirus 1, Equid
  • Herpesvirus Vaccines / therapeutic use
  • Antibodies, Viral
  • Vaccination / veterinary
  • Herpesviridae Infections / prevention & control
  • Herpesviridae Infections / veterinary
  • Horse Diseases / prevention & control

References

This article includes 44 references
  1. Patel JR, Heldens J. Equine herpesviruses 1 (EHV-1) and 4 (EHV-4)-epidemiology, disease and immunoprophylaxis: a brief review.. Vet J 2005;170:14-23.
    doi: 10.1016/j.tvjl.2004.04.018google scholar: lookup
  2. Oladunni FS, Horohov DW, Chambers TM. EHV-1: a constant threat to the horse industry.. Front Microbiol 2019;10:2668.
    doi: 10.3389/fmicb.2019.02668google scholar: lookup
  3. Foote CE, Gilkerson JR, Whalley JM, Love DN. Seroprevalence of equine herpesvirus 1 in mares and foals on a large Hunter Valley stud farm in years pre- and postvaccination.. Aust Vet J 2003;81:283-8.
    doi: 10.1111/j.1751-0813.2003.tb12576.xgoogle scholar: lookup
  4. Brown JA, Mapes S, Ball BA, Hodder AD, Liu IK, Pusterla N. Prevalence of equine herpesvirus-1 infection among thoroughbreds residing on a farm on which the virus was endemic.. J Am Vet Med Assoc 2007;231:577-80.
    doi: 10.2460/javma.231.4.577google scholar: lookup
  5. Lunn DP, Davis-Poynter N, Flaminio MJ, Horohov DW, Osterrieder K, Pusterla N. Equine herpesvirus-1 consensus statement.. J Vet Intern Med 2009;23:450-61.
    doi: 10.1111/j.1939-1676.2009.0304.xgoogle scholar: lookup
  6. Allen GP. Respiratory infections by equine herpesvirus types 1 and 4.. Equine respiratory diseases Ithaca NY: International Veterinary Information Service; 2002. p. 2 [accessed 2021 November 11].
  7. Defra/AHT/BEVA Equine Quarterly Disease Surveillance Reports. 2011 [accessed 2021 November 11]. Available from: https://www.jdata.co.za/iccviewer/media/dsr
  8. Perkins GA, Goodman LB, Tsujimura K, Van de Walle GR, Kim SG, Dubovi EJ. Investigation of the prevalence of neurologic equine herpes virus type 1 (EHV-1) in a 23-year retrospective analysis (1984-2007).. Vet Microbiol 2009;139:375-8.
    doi: 10.1016/j.vetmic.2009.06.033google scholar: lookup
  9. Smith KC, Blunden AS, Whitwell KE, Dunn KA, Wales AD. A survey of equine abortion, stillbirth and neonatal death in the UK from 1988 to 1997.. Equine Vet J 2003;35:496-501.
    doi: 10.2746/042516403775600578google scholar: lookup
  10. Vissani MA, Becerra ML, Olguín Perglione C, Tordoya MS, Miño S, Barrandeguy M. Neuropathogenic and non-neuropathogenic genotypes of equid herpesvirus type 1 in Argentina.. Vet Microbiol 2009;139:361-4.
    doi: 10.1016/j.vetmic.2009.06.025google scholar: lookup
  11. Lesté-Lasserre C. Deadly viral outbreak ravages European horses.. Science 2021;371:1297.
    doi: 10.1126/science.371.6536.1297google scholar: lookup
  12. Vereecke N, Carnet F, Pronost S, Vanschandevijl K, Theuns S, Nauwynck H. Genome sequences of equine herpesvirus 1 strains from a European outbreak of neurological disorders linked to a horse gathering in Valencia, Spain, in 2021.. Microbiol Resour Announc 2021;10:e00333-21.
    doi: 10.1128/mra.00333-21google scholar: lookup
  13. Kydd JH, Townsend HG, Hannant D. The equine immune response to equine herpesvirus-1: the virus and its vaccines.. Vet Immunol Immunopathol 2006;111:15-30.
    doi: 10.1016/j.vetimm.2006.01.005google scholar: lookup
  14. Slater J, Hannant D. Equine immunity to viruses.. Vet Clin North Am Equine Pract 2000;16:49-68.
  15. Pusterla N, Hatch K, Crossley B, Wademan C, Barnum S, Flynn K. Equine herpesvirus-1 genotype did not significantly affect clinical signs and disease outcome in 65 horses diagnosed with equine herpesvirus-1 myeloencephalopathy.. Vet J 2020;255:105407.
    doi: 10.1016/j.tvjl.2019.105407google scholar: lookup
  16. Pusterla N, Barnum S, Miller J, Varnell S, Dallap-Schaer B, Aceto H. Investigation of an EHV-1 outbreak in the United States caused by a new H752 genotype.. Pathogens 2021;10:747.
    doi: 10.3390/pathogens10060747google scholar: lookup
  17. Minke JM, Audonnet JC, Fischer L. Equine viral vaccines: the past, present and future.. Vet Res 2004;35:425-43.
    doi: 10.1051/vetres:2004019google scholar: lookup
  18. Barquero N, Gilkerson JR, Newton JR. Evidence-based immunization in horses.. Vet Clin North Am Equine Pract 2007;23:481-508.
    doi: 10.1016/j.cveq.2007.04.003google scholar: lookup
  19. van der Meulen KM, Gryspeerdt AC, Vandekerckhove AA, Garre BA, Nauwynck HJ. The protective properties of vaccination against equine herpesvirus 1-induced viremia, abortion and nervous system disorders.. Vlaams Diergeneeskundig Tijdschrift 2007;76:186-94.
  20. Patel JR, Heldens JG. Immunoprophylaxis against important virus disease of horses, farm animals and birds.. Vaccine 2009;27:1797-810.
    doi: 10.1016/j.vaccine.2008.12.063google scholar: lookup
  21. Khusro A, Aarti C, Rivas-Caceres RR, Barbabosa-Pliego A. Equine herpesvirus-I infection in horses: recent updates on its pathogenicity, vaccination, and preventive management strategies.. J Equine Vet Sci 2020;87:102923.
    doi: 10.1016/j.jevs.2020.102923google scholar: lookup
  22. Sackett DL. Introduction.. 2000. p. 1-12.
  23. Jadad AR, Moore RA, Carroll D, Jenkinson C, Reynolds DJ, Gavaghan DJ. Assessing the quality of reports of randomized clinical trials: is blinding necessary?. Control Clin Trials 1996;17:1-12.
    doi: 10.1016/0197-2456(95)00134-4google scholar: lookup
  24. O'Connor AM, Sargeant JM, Gardner IA, Dickson JS, Torrence ME, Consensus Meeting Participants. The REFLECT statement: methods and processes of creating reporting guidelines for randomized controlled trials for livestock and food safety by modifying the CONSORT statement.. Zoonoses Public Health 2010;57:95-104.
    doi: 10.1111/j.1863-2378.2009.01311.xgoogle scholar: lookup
  25. Sargeant JM, O'Connor AM, Gardner IA, Dickson JS, Torrence ME, Consensus Meeting Participants. The REFLECT statement: reporting guidelines for randomized controlled trials in livestock and food safety: explanation and elaboration.. Zoonoses Public Health 2010;57:105-36.
    doi: 10.1111/j.1863-2378.2009.01312.xgoogle scholar: lookup
  26. Thrusfield M. Systematic reviews.. 2018. p. 397-420.
  27. Hannant D, Jessett DM, O'Neill T, Dolby CA, Cook RF, Mumford JA. Responses of ponies to equid herpesvirus-1 ISCOM vaccination and challenge with virus of the homologous strain.. Res Vet Sci 1993;54:299-305.
    doi: 10.1016/0034-5288(93)90126-zgoogle scholar: lookup
  28. Breathnach CC, Yeargan MR, Sheoran AS, Allen GP. The mucosal humoral immune response of the horse to infective challenge and vaccination with equine herpesvirus-1 antigens.. Equine Vet J 2001;33:651-7.
    doi: 10.2746/042516401776249318google scholar: lookup
  29. Heldens JG, Hannant D, Cullinane AA, Prendergast MJ, Mumford JA, Nelly M. Clinical and virological evaluation of the efficacy of an inactivated EHV1 and EHV4 whole virus vaccine (Duvaxyn EHV1,4). Vaccination/challenge experiments in foals and pregnant mares.. Vaccine 2001;19:4307-17.
    doi: 10.1016/s0264-410x(01)00131-1google scholar: lookup
  30. Minke JM, Fischer L, Baudu P, Guigal PM, Sindle T, Mumford JA. Use of DNA and recombinant canarypox viral (ALVAC) vectors for equine herpes virus vaccination.. Vet Immunol Immunopathol 2006;111:47-57.
    doi: 10.1016/j.vetimm.2006.01.008google scholar: lookup
  31. Goodman LB, Wagner B, Flaminio MJ, Sussman KH, Metzger SM, Holland R. Comparison of the efficacy of inactivated combination and modified-live virus vaccines against challenge infection with neuropathogenic equine herpesvirus type 1 (EHV-1).. Vaccine 2006;24:3636-45.
    doi: 10.1016/j.vaccine.2006.01.062google scholar: lookup
  32. Goehring LS, Wagner B, Bigbie R, Hussey SB, Rao S, Morley PS. Control of EHV-1 viremia and nasal shedding by commercial vaccines.. Vaccine 2010;28:5203-11.
    doi: 10.1016/j.vaccine.2010.05.065google scholar: lookup
  33. Perkins G, Babasyan S, Stout AE, Freer H, Rollins A, Wimer CL. Intranasal IgG4/7 antibody responses protect horses against equid herpesvirus-1 (EHV-1) infection including nasal virus shedding and cell-associated viremia.. Virology 2019;531:219-32.
    doi: 10.1016/j.virol.2019.03.014google scholar: lookup
  34. Schnabel CL, Babasyan S, Rollins A, Freer H, Wimer CL, Perkins G. An equine herpesvirus type 1 (EHV-1) Ab4 open reading frame 2 deletion mutant provides immunity and protection from EHV-1 infection and disease.. J Virol 2019;93:e01011-9.
    doi: 10.1128/jvi.01011-19google scholar: lookup
  35. Schnabel CL, Wimer CL, Perkins G, Babasyan S, Freer H, Watts C. Deletion of the ORF2 gene of the neuropathogenic equine herpesvirus type 1 strain Ab4 reduces virulence while maintaining strong immunogenicity.. BMC Vet Res 2018;14:245.
    doi: 10.1186/s12917-018-1563-4google scholar: lookup
  36. Wimer CL, Schnabel CL, Perkins G, Babasyan S, Freer H, Stout AE. The deletion of the ORF1 and ORF71 genes reduces virulence of the neuropathogenic EHV-1 strain Ab4 without compromising host immunity in horses.. PLoS One 2018;13(11):e0206679.
    doi: 10.1371/journal.pone.0206679google scholar: lookup
  37. Burns MJ, O'Connor AM. Assessment of methodological quality and sources of variation in the magnitude of vaccine efficacy: a systematic review of studies from 1960 to 2005 reporting immunization with Moraxella bovis vaccines in young cattle.. Vaccine 2008;26:144-52.
    doi: 10.1016/j.vaccine.2007.10.014google scholar: lookup
  38. Halasa T, Boklund A, Cox S, Enøe C. Meta-analysis on the efficacy of foot-and-mouth disease emergency vaccination.. Prev Vet Med 2011;98:1-9.
    doi: 10.1016/j.prevetmed.2010.08.005google scholar: lookup
  39. Bryant NA, Wilkie GS, Russell CA, Compston L, Grafham D, Clissold L. Genetic diversity of equine herpesvirus 1 isolated from neurological, abortigenic and respiratory disease outbreaks.. Transbound Emerg Dis 2018;65:817-32.
    doi: 10.1111/tbed.12809google scholar: lookup
  40. Dunowska M. A review of equid herpesvirus 1 for the veterinary practitioner. Part A: clinical presentation, diagnosis and treatment.. N Z Vet J 2014;62:171-8.
    doi: 10.1080/00480169.2014.899945google scholar: lookup
  41. Grindlay DJC, Brennan ML, Dean RS. Searching the veterinary literature: a comparison of the coverage of veterinary journals by nine bibliographic databases.. J Vet Med Educ 2012;39:404-12.
    doi: 10.3138/jvme.1111.109rgoogle scholar: lookup
  42. Falagas ME, Pitsouni EI, Malietzis GA, Pappas G. Comparison of PubMed, Scopus, web of science, and Google scholar: strengths and weaknesses.. FASEB J 2008;22:338-42.
    doi: 10.1096/fj.07-9492lsfgoogle scholar: lookup
  43. EFSA, European Food Safety Authority. Application of systematic review methodology to food and feed safety assessments to support decision making.. EFSA J 2010;8:1637.
  44. Guyatt GH, Oxman AD, Vist GE, Kunz R, Falck-Ytter Y, Alonso-Coello P. GRADE: an emerging consensus on rating quality of evidence and strength of recommendations.. BMJ 2008;336:924-6.
    doi: 10.1136/bmj.39489.470347.adgoogle scholar: lookup

Citations

This article has been cited 9 times.
  1. Kutumbetov L, Myrzakhmetova B, Tussipova A, Zhapparova G, Tlenchiyeva T, Bissenbayeva K, Nurabayev S, Kerimbayev A. Development and Preclinical Evaluation of a Lyophilized Vaccine Against Equine Herpesvirus Type 4 (EHV-4). Vaccines (Basel) 2025 May 31;13(6).
    doi: 10.3390/vaccines13060604pubmed: 40573935google scholar: lookup
  2. de la Cuesta-Torrado M, Vitale V, Velloso Alvarez A, Neira-Egea P, Diss C, Cuervo-Arango J. The Effect of Vaccination Status on Total Lymphocyte Count in Horses Affected by Equine Herpes Virus-1 Myeloencephalopathy. Animals (Basel) 2025 Apr 1;15(7).
    doi: 10.3390/ani15071019pubmed: 40218411google scholar: lookup
  3. de la Cuesta-Torrado M, Velloso Alvarez A, Santiago-Llorente I, Armengou L, Nieto F, Ríos J, Cruz-López F, Jose-Cunilleras E. Risk Factors and Long-Term Outcomes in Horses After the 2021 Outbreak of Equine Herpesvirus 1 Myeloencephalopathy, Valencia, Spain. J Vet Intern Med 2025 Mar-Apr;39(2):e70040.
    doi: 10.1111/jvim.70040pubmed: 40055829google scholar: lookup
  4. de la Cuesta-Torrado M, Velloso Alvarez A, Cárdenas-Rebollo JM, Neira-Egea P, Vitale V, Cuervo-Arango J. Comparison of clinical variables and outcome of 2 natural equine herpesvirus myeloencephalopathy outbreaks induced by equine herpesvirus-1 A2254/N752 strain in sport horses. J Vet Intern Med 2025 Jan-Feb;39(1):e17287.
    doi: 10.1111/jvim.17287pubmed: 39778904google scholar: lookup
  5. Arroyo LG, Gomez DE, Moore A, Papapetrou M, Lillie BN. Molecular testing for equine herpesviruses 1 (EHV-1) in healthy postpartum broodmares. Can Vet J 2024 Aug;65(8):813-816.
    pubmed: 39091477
  6. Schramm A, Ackermann M, Eichwald C, Aguilar C, Fraefel C, Lechmann J. Antibody reactions of horses against various domains of the EHV-1 receptor-binding protein gD1. PLoS One 2024;19(7):e0301987.
    doi: 10.1371/journal.pone.0301987pubmed: 38995916google scholar: lookup
  7. Giessler KS, Goehring LS, Jacob SI, Davis A, Esser MM, Lee Y, Zarski LM, Weber PSD, Hussey GS. Impact of the host immune response on the development of equine herpesvirus myeloencephalopathy in horses. J Gen Virol 2024 May;105(5).
    doi: 10.1099/jgv.0.001987pubmed: 38767608google scholar: lookup
  8. Goehring L, Dorman DC, Osterrieder K, Burgess BA, Dougherty K, Gross P, Neinast C, Pusterla N, Soboll-Hussey G, Lunn DP. Pharmacologic interventions for the treatment of equine herpesvirus-1 in domesticated horses: A systematic review. J Vet Intern Med 2024 May-Jun;38(3):1892-1905.
    doi: 10.1111/jvim.17016pubmed: 38380685google scholar: lookup
  9. Osterrieder K, Dorman DC, Burgess BA, Goehring LS, Gross P, Neinast C, Pusterla N, Hussey GS, Lunn DP. Vaccination for the prevention of equine herpesvirus-1 disease in domesticated horses: A systematic review and meta-analysis. J Vet Intern Med 2024 May-Jun;38(3):1858-1871.
    doi: 10.1111/jvim.16895pubmed: 37930113google scholar: lookup
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