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Frontiers in veterinary science2019; 6; 59; doi: 10.3389/fvets.2019.00059

Histopathologic Findings Following Experimental Equine Herpesvirus 1 Infection of Horses.

Abstract: Histopathological differences in horses infected with equine herpesvirus type 1 (EHV-1) of differing neuropathogenic potential [wild-type (Ab4), polymerase mutant (Ab4 N752), EHV-1/4 gD mutant (Ab4 gD4)] were evaluated to examine the impact of viral factors on clinical disease, tissue tropism and pathology. Three of 8 Ab4 infected horses developed Equine Herpesvirus Myeloencephalopathy (EHM) requiring euthanasia of 2 horses on day 9 post-infection. None of the other horses showed neurologic signs and all remaining animals were sacrificed 10 weeks post-infection. EHM horses had lymphohistiocytic vasculitis and lymphocytic infiltrates in the lungs, spinal cord, endometrium and eyes. EHV-1 antigen was detected within the eyes and spinal cord. In 3/6 of the remaining Ab4 infected horses, 4/9 Ab4 N752 infected horses, and 8/8 Ab4 gD4 infected horses, choroiditis was observed. All males had interstitial lymphoplasmacytic and/or histiocytic orchitis and EHV-1 antigen was detected. In conclusion, only animals sacrificed due to EHM developed overt vasculitis in the CNS and the eye. Mild choroiditis persisted in many animals and appeared to be more common in Ab4 gD4 infected animals. Finally, we report infiltrates and changes in the reproductive organs of all males associated with EHV-1 antigen. While the exact significance of these changes is unclear, these findings raise concern for long-term effects on reproduction and prolonged shedding of virus through semen.
Publication Date: 2019-03-04 PubMed ID: 30886853PubMed Central: PMC6409500DOI: 10.3389/fvets.2019.00059Google Scholar: Lookup
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  • Journal Article

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 investigates the impact of different strains of Equine Herpesvirus type 1 (EHV-1) on horses, focusing on the physical changes observed in horses’ bodies following infection. The study identifies differences such as vasculitis and choroiditis as potential effects of EHV-1 infection, and raises concerns over its possible influence on equine reproduction and persistent viral shedding.

Study Design and Procedure

  • The researchers infected horses with different variants of EHV-1—wild-type (Ab4), Ab4 N752, and Ab4 gD4—to assess the effect of the virus’s characteristics on the resultant disease, as well as its predilection for specific tissues (tissue tropism) and the associated pathological findings.
  • Outcomes were monitored over a 10-week period following infection, with severely affected horses euthanised earlier when necessary due to a severe neurological condition resulting from the EHV-1 infection called Equine Herpesvirus Myeloencephalopathy (EHM).
  • The course of infection was then studied through pathological findings in different tissues in the body of the horse.

Findings

  • Only horses infected with the wild-type Ab4 strain developed EHM, out of which two were euthanised on the ninth day following infection.
  • The study observed inflammation of blood vessels (vasculitis) and cellular infiltrations in different tissues such as the lungs, spinal cord, and eye. In some cases, EHV-1 antigen (a substance that triggers an immune response) was also detected in the eyes and spinal cord.
  • About half of the horses infected with the various EHV-1 strains developed choroiditis—an inflammation of the vascular layer of the eye—indicating a possible eye-related complication of EHV-1 infection.
  • All male horses showed abnormalities in their reproductive organs, with consistent detection of EHV-1 antigen noticed.

Implications and Conclusions

  • The research draws attention to the potential impacts of EHV-1 infection, particularly the neurological disorder, EHM, mainly caused by the wild-type Ab4 variant of the virus.
  • It also highlights ocular problems, such as choroiditis, and reproductive anomalies which were common among infected horses. The presence of EHV-1 antigen in the reproductive organs raises concerns about the virus’s possible long-term effects on equine reproduction and its ability to continue shedding/scattering from the body through semen—a process which could potentially facilitate the virus’s transmission.
  • Though further research is needed to fully understand the implications of these findings, this study sheds light on the varied impacts of EHV-1 infection on horses and the potential risks it poses to horse health and reproduction.

Cite This Article

APA
Holz CL, Sledge DG, Kiupel M, Nelli RK, Goehring LS, Soboll Hussey G. (2019). Histopathologic Findings Following Experimental Equine Herpesvirus 1 Infection of Horses. Front Vet Sci, 6, 59. https://doi.org/10.3389/fvets.2019.00059

Publication

ISSN: 2297-1769
NlmUniqueID: 101666658
Country: Switzerland
Language: English
Volume: 6
Pages: 59
PII: 59

Researcher Affiliations

Holz, Carine L
  • Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI, United States.
Sledge, Dodd G
  • Veterinary Diagnostic Laboratory, College of Veterinary Medicine, Michigan State University, Lansing, MI, United States.
Kiupel, Matti
  • Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI, United States.
  • Veterinary Diagnostic Laboratory, College of Veterinary Medicine, Michigan State University, Lansing, MI, United States.
Nelli, Rahul K
  • Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI, United States.
Goehring, Lutz S
  • Equine Hospital - Division of Medicine and Reproduction, Ludwig-Maximilians University, Munich, Germany.
Soboll Hussey, Gisela
  • Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI, United States.

References

This article includes 52 references
  1. Bryans JT, Allen GP. Herpesviral diseases of the horse. In: Wittmann G, editor. Herpesvirus Diseases of Cattle, Horses, and Pigs. Boston, MA: Kluwer; (1989). p. 176–229.
  2. Patel JR, Heldens J. Equine herpesviruses 1 (EHV-1) and 4 (EHV-4)--epidemiology, disease and immunoprophylaxis: a brief review.. Vet J 2005 Jul;170(1):14-23.
    doi: 10.1016/j.tvjl.2004.04.018pubmed: 15993786google scholar: lookup
  3. van Maanen C. Equine herpesvirus 1 and 4 infections: an update.. Vet Q 2002 Jun;24(2):58-78.
    doi: 10.1080/01652176.2002.9695126pubmed: 12095082google scholar: lookup
  4. Allen GP, Kydd JH, Slater JD, Smith KC. Equid herpesvirus 1 and equid herpesvirus 4 infections. In: Jawt C, editor. Infectious Diseases of Livestock. Vol. 2. Newmarket, ON: Oxford University Press; (2004). p. 829–59.
  5. Hussey GS, Goehring LS, Lunn DP, Hussey SB, Huang T, Osterrieder N, Powell C, Hand J, Holz C, Slater J. Experimental infection with equine herpesvirus type 1 (EHV-1) induces chorioretinal lesions.. Vet Res 2013 Dec 5;44(1):118.
    doi: 10.1186/1297-9716-44-118pmc: PMC4028784pubmed: 24308772google scholar: lookup
  6. Allen GP, Bryans JT. Molecular epizootiology, pathogenesis, and prophylaxis of equine herpesvirus-1 infections.. Prog Vet Microbiol Immunol 1986;2:78-144.
    pubmed: 2856183
  7. Smith KC, Mumford JA, Lakhani K. A comparison of equid herpesvirus-1 (EHV-1) vascular lesions in the early versus late pregnant equine uterus.. J Comp Pathol 1996 Apr;114(3):231-47.
    doi: 10.1016/S0021-9975(96)80045-4pubmed: 8762581google scholar: lookup
  8. Wilson WD. Equine herpesvirus 1 myeloencephalopathy.. Vet Clin North Am Equine Pract 1997 Apr;13(1):53-72.
    doi: 10.1016/S0749-0739(17)30255-9pubmed: 9106343google scholar: lookup
  9. Matsumura T, Sugiura T, Imagawa H, Fukunaga Y, Kamada M. Epizootiological aspects of type 1 and type 4 equine herpesvirus infections among horse populations.. J Vet Med Sci 1992 Apr;54(2):207-11.
    doi: 10.1292/jvms.54.207pubmed: 1318750google scholar: lookup
  10. Osterrieder N, Van de Walle GR. Pathogenic potential of equine alphaherpesviruses: the importance of the mononuclear cell compartment in disease outcome.. Vet Microbiol 2010 Jun 16;143(1):21-8.
    doi: 10.1016/j.vetmic.2010.02.010pubmed: 20202764google scholar: lookup
  11. Verheyen K, Newton JR, Wood JL, Birch-Machin I, Hannant D, Humberstone RW. Possible case of EHV-4 ataxia in warmblood mare.. Vet Rec 1998 Oct 17;143(16):456.
    pubmed: 9823615
  12. Jones C. Alphaherpesvirus latency: its role in disease and survival of the virus in nature.. Adv Virus Res 1998;51:81-133.
    doi: 10.1016/S0065-3527(08)60784-8pubmed: 9891586google scholar: lookup
  13. Barrow AD, Burgess SC, Baigent SJ, Howes K, Nair VK. Infection of macrophages by a lymphotropic herpesvirus: a new tropism for Marek's disease virus.. J Gen Virol 2003 Oct;84(Pt 10):2635-2645.
    doi: 10.1099/vir.0.19206-0pubmed: 13679597google scholar: lookup
  14. Slater JD, Borchers K, Thackray AM, Field HJ. The trigeminal ganglion is a location for equine herpesvirus 1 latency and reactivation in the horse.. J Gen Virol 1994 Aug;75 ( Pt 8):2007-16.
    doi: 10.1099/0022-1317-75-8-2007pubmed: 8046404google scholar: lookup
  15. Taouji S, Collobert C, Gicquel B, Sailleau C, Brisseau N, Moussu C, Breuil MF, Pronost S, Borchers K, Zientara S. Detection and isolation of equine herpesviruses 1 and 4 from horses in Normandy: an autopsy study of tissue distribution in relation to vaccination status.. J Vet Med B Infect Dis Vet Public Health 2002 Oct;49(8):394-9.
  16. Welch HM, Bridges CG, Lyon AM, Griffiths L, Edington N. Latent equid herpesviruses 1 and 4: detection and distinction using the polymerase chain reaction and co-cultivation from lymphoid tissues.. J Gen Virol 1992 Feb;73 ( Pt 2):261-8.
    doi: 10.1099/0022-1317-73-2-261pubmed: 1347078google scholar: lookup
  17. Pusterla N, Leutenegger CM, Wilson WD, Watson JL, Ferraro GL, Madigan JE. Equine herpesvirus-4 kinetics in peripheral blood leukocytes and nasopharyngeal secretions in foals using quantitative real-time TaqMan PCR.. J Vet Diagn Invest 2005 Nov;17(6):578-81.
    doi: 10.1177/104063870501700610pubmed: 16475518google scholar: lookup
  18. Borchers K, Wolfinger U, Lawrenz B, Schellenbach A, Ludwig H. Equine herpesvirus 4 DNA in trigeminal ganglia of naturally infected horses detected by direct in situ PCR.. J Gen Virol 1997 May;78 ( Pt 5):1109-14.
    doi: 10.1099/0022-1317-78-5-1109pubmed: 9152430google scholar: lookup
  19. Goehring LS, Lunn DP. Equine herpesvirus myeloencephalopathy. In: Robinson NE,, Sprayberry K, editors. Current Therapy in Equine Medicine. 6th ed. St. Louis, MO: Saunders; (2008). p. 177–81.
  20. Goehring LS, van Maanen C, Berendsen M, Cullinane A, de Groot RJ, Rottier PJ, Wesselingh JJ, Sloet van Oldruitenborgh-Oosterbaan MM. Experimental infection with neuropathogenic equid herpesvirus type 1 (EHV-1) in adult horses.. Vet J 2010 Nov;186(2):180-7.
    doi: 10.1016/j.tvjl.2009.08.007pubmed: 19726209google scholar: lookup
  21. Whitwell KE, Gower SM, Smith KC. An immunoperoxidase method applied to the diagnosis of equine herpesvirus abortion, using conventional and rapid microwave techniques.. Equine Vet J 1992 Jan;24(1):10-2.
  22. Foote AK, Ricketts SW, Whitwell KE. A racing start in life? The hurdles of equine feto-placental pathology.. Equine Vet J Suppl 2012 Feb;(41):120-9.
  23. Lunn DP, Davis-Poynter N, Flaminio MJ, Horohov DW, Osterrieder K, Pusterla N, Townsend HG. Equine herpesvirus-1 consensus statement.. J Vet Intern Med 2009 May-Jun;23(3):450-61.
  24. Smith KC. Herpesviral abortion in domestic animals.. Vet J 1997 May;153(3):253-68.
    doi: 10.1016/S1090-0233(97)80061-5pubmed: 9232116google scholar: lookup
  25. Zanuzzi CN, Bravi ME, Scrochi MR, Nishida F, Fuentealba NA, Diessler ME, Sguazza HG, Muglia CI, Gimeno EJ, Portiansky EL, Barbeito CG, Galosi CM. Microvascular lesions and changes in cell proliferation and death, and cytokine expression in the placentas of mice experimentally infected with Equid Herpesvirus 1.. Res Vet Sci 2016 Dec;109:121-128.
    doi: 10.1016/j.rvsc.2016.09.005pubmed: 27892860google scholar: lookup
  26. Negussie H, Li Y, Tessema TS, Nauwynck HJ. Replication characteristics of equine herpesvirus 1 and equine herpesvirus 3: comparative analysis using ex vivo tissue cultures.. Vet Res 2016 Jan 15;47:19.
    doi: 10.1186/s13567-016-0305-5pmc: PMC4714513pubmed: 26768993google scholar: lookup
  27. Fritsche AK, Borchers K. Detection of neuropathogenic strains of Equid Herpesvirus 1 (EHV-1) associated with abortions in Germany.. Vet Microbiol 2011 Jan 10;147(1-2):176-80.
    doi: 10.1016/j.vetmic.2010.06.014pubmed: 20619972google scholar: lookup
  28. Hebia-Fellah I, Léauté A, Fiéni F, Zientara S, Imbert-Marcille BM, Besse B, Fortier G, Pronost S, Miszczak F, Ferry B, Thorin C, Pellerin JL, Bruyas JF. Evaluation of the presence of equine viral herpesvirus 1 (EHV-1) and equine viral herpesvirus 4 (EHV-4) DNA in stallion semen using polymerase chain reaction (PCR).. Theriogenology 2009 Jun;71(9):1381-9.
  29. Walter J, Balzer HJ, Seeh C, Fey K, Bleul U, Osterrieder N. Venereal shedding of equid herpesvirus-1 (EHV-1) in naturally infected stallions.. J Vet Intern Med 2012 Nov-Dec;26(6):1500-4.
  30. Tearle JP, Smith KC, Boyle MS, Binns MM, Livesay GJ, Mumford JA. Replication of equid herpesvirus-1 (EHV-1) in the testes and epididymides of ponies and venereal shedding of infectious virus.. J Comp Pathol 1996 Nov;115(4):385-97.
    doi: 10.1016/S0021-9975(96)80073-9pubmed: 9004080google scholar: lookup
  31. Allen GP, Umphenour NW. Equine Coital Exanthema. Infectious Diseases of Livestock. Cape Town: Oxford Press; (2004).
  32. Wrathall AE, Simmons HA, Van Soom A. Evaluation of risks of viral transmission to recipients of bovine embryos arising from fertilisation with virus-infected semen.. Theriogenology 2006 Jan 20;65(2):247-74.
  33. Romero CH, Meade PN, Shultz JE, Chung HY, Gibbs EP, Hahn EC, Lollis G. Venereal transmission of pseudorabies viruses indigenous to feral swine.. J Wildl Dis 2001 Apr;37(2):289-96.
    doi: 10.7589/0090-3558-37.2.289pubmed: 11310879google scholar: lookup
  34. Evdokimov VV, Naumenko VA, Tulenev YA, Kurilo LF, Kovalyk VP, Sorokina TM, Lebedeva AL, Gomberg MA, Kushch AA. [QUANTITATIVE DNA EVALUATION OF THE HIGH CARCINOGENIC RISK OF HUMAN PAPILLOMA VIRUSES AND HUMAN HERPES VIRUSES IN MALES WITH FERTILITY DISORDERS].. Vopr Virusol 2016;61(2):63-8.
    pubmed: 27451497
  35. Malolina EA, Kulibin AIu, Tiulenev IuA, Kushch AA. [Destructive changes in the mice testes in retrograde infection with herpes simplex virus].. Urologiia 2013 Jul-Aug;(4):55-9.
    pubmed: 24159767
  36. Malolina EA, Kulibin AY, Naumenko VA, Gushchina EA, Zavalishina LE, Kushch AA. Herpes simplex virus inoculation in murine rete testis results in irreversible testicular damage.. Int J Exp Pathol 2014 Apr;95(2):120-30.
    doi: 10.1111/iep.12071pmc: PMC3960039pubmed: 24673915google scholar: lookup
  37. Slater JD, Gibson JS, Barnett KC, Field HJ. Chorioretinopathy associated with neuropathology following infection with equine herpesvirus-1.. Vet Rec 1992 Sep 12;131(11):237-9.
    doi: 10.1136/vr.131.11.237-apubmed: 1332242google scholar: lookup
  38. Slater JD. Fluorescein angiographic appearance of the normal fundus and of focal chorioretinal lesions in the horse. Invest Ophthalmol Vis Sci (1995) 11(Suppl. 1):2–7.
  39. Pusterla N, Hussey GS. Equine herpesvirus 1 myeloencephalopathy.. Vet Clin North Am Equine Pract 2014 Dec;30(3):489-506.
    doi: 10.1016/j.cveq.2014.08.006pubmed: 25300635google scholar: lookup
  40. Nugent J, Birch-Machin I, Smith KC, Mumford JA, Swann Z, Newton JR, Bowden RJ, Allen GP, Davis-Poynter N. Analysis of equid herpesvirus 1 strain variation reveals a point mutation of the DNA polymerase strongly associated with neuropathogenic versus nonneuropathogenic disease outbreaks.. J Virol 2006 Apr;80(8):4047-60.
  41. Gardiner DW, Lunn DP, Goehring LS, Chiang YW, Cook C, Osterrieder N, McCue P, Del Piero F, Hussey SB, Hussey GS. Strain impact on equine herpesvirus type 1 (EHV-1) abortion models: viral loads in fetal and placental tissues and foals.. Vaccine 2012 Oct 12;30(46):6564-72.
    doi: 10.1016/j.vaccine.2012.08.046pubmed: 22944628google scholar: lookup
  42. Crowhurst FA, Dickinson G, Burrows R. An outbreak of paresis in mares and geldings associated with equid herpesvirus 1.. Vet Rec 1981 Dec 12;109(24):527-8.
    pubmed: 6280366
  43. Goodman LB, Loregian A, Perkins GA, Nugent J, Buckles EL, Mercorelli B, Kydd JH, Palù G, Smith KC, Osterrieder N, Davis-Poynter N. A point mutation in a herpesvirus polymerase determines neuropathogenicity.. PLoS Pathog 2007 Nov;3(11):e160.
  44. Holz CL, Nelli RK, Wilson ME, Zarski LM, Azab W, Baumgardner R, Osterrieder N, Pease A, Zhang L, Hession S, Goehring LS, Hussey SB, Soboll Hussey G. Viral genes and cellular markers associated with neurological complications during herpesvirus infections.. J Gen Virol 2017 Jun;98(6):1439-1454.
    doi: 10.1099/jgv.0.000773pubmed: 28631601google scholar: lookup
  45. Smith KC, Whitwell KE, Binns MM, Dolby CA, Hannant D, Mumford JA. Abortion of virologically negative foetuses following experimental challenge of pregnant pony mares with equid herpesvirus 1.. Equine Vet J 1992 Jul;24(4):256-9.
  46. Goehring LS, van Winden SC, van Maanen C, Sloet van Oldruitenborgh-Oosterbaan MM. Equine herpesvirus type 1-associated myeloencephalopathy in The Netherlands: a four-year retrospective study (1999-2003).. J Vet Intern Med 2006 May-Jun;20(3):601-7.
  47. Stierstorfer B, Eichhorn W, Schmahl W, Brandmüller C, Kaaden OR, Neubauer A. Equine herpesvirus type 1 (EHV-1) myeloencephalopathy: a case report.. J Vet Med B Infect Dis Vet Public Health 2002 Feb;49(1):37-41.
  48. Whitwell KE, Blunden AS. Pathological findings in horses dying during an outbreak of the paralytic form of Equid herpesvirus type 1 (EHV-1) infection.. Equine Vet J 1992 Jan;24(1):13-9.
  49. Goodman LB, Wagner B, Flaminio MJ, Sussman KH, Metzger SM, Holland R, Osterrieder N. 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 Apr 24;24(17):3636-45.
    doi: 10.1016/j.vaccine.2006.01.062pubmed: 16513225google scholar: lookup
  50. Zarski LM, Kim S, Soboll Hussey G. Potential of Administration of Recombinant Adenovirus Expressing Inhibitory IR2 Protein for Control of Equine Herpesvirus 1 Disease in Horses. Vancouver, CA: IHW; (2018).
  51. Blunden AS, Smith KC, Whitwell KE, Dunn KA. Systemic infection by equid herpesvirus-1 in a Grevy's zebra stallion (Equus grevyi) with particular reference to genital pathology.. J Comp Pathol 1998 Nov;119(4):485-93.
    doi: 10.1016/S0021-9975(98)80043-1pubmed: 9839210google scholar: lookup
  52. Smith KC, Tearle JP, Boyle MS, Gower SM, Mumford JA. Replication of equid herpesvirus-1 in the vaginal tunics of colts following local inoculation.. Res Vet Sci 1993 Mar;54(2):249-51.
    doi: 10.1016/0034-5288(93)90066-Opubmed: 8384729google scholar: lookup

Citations

This article has been cited 10 times.
  1. Elste J, Chan A, Patil C, Tripathi V, Shadrack DM, Jaishankar D, Hawkey A, Mungerson MS, Shukla D, Tiwari V. Archaic connectivity between the sulfated heparan sulfate and the herpesviruses - An evolutionary potential for cross-species interactions. Comput Struct Biotechnol J 2023;21:1030-1040.
    doi: 10.1016/j.csbj.2023.01.005pubmed: 36733705google scholar: lookup
  2. Barbosa JD, Lins AMC, Bomjardim HDA, Silveira NDSES, Barbosa CC, Beuttemmuller EA, Brito MF, Salvarani FM. Equine Herpesvirus Type 1 Myeloencephalitis in the Brazilian Amazon. Animals (Basel) 2022 Dec 23;13(1).
    doi: 10.3390/ani13010059pubmed: 36611668google scholar: lookup
  3. Hu Y, Jia Q, Liu J, Sun W, Bao Z, Che C, Wu G, Fan B, Jarhen, Ran D. Molecular characteristics and pathogenicity of an equid alphaherpesvirus 1 strain isolated in China. Virus Genes 2022 Aug;58(4):284-293.
    doi: 10.1007/s11262-022-01910-ypubmed: 35567668google scholar: lookup
  4. Nielsen SS, Alvarez J, Bicout DJ, Calistri P, Canali E, Drewe JA, Garin-Bastuji B, Gonzales Rojas JL, Gortázar C, Herskin M, Michel V, Miranda Chueca MÁ, Roberts HC, Padalino B, Pasquali P, Spoolder H, Ståhl K, Calvo AV, Viltrop A, Winckler C, Carvelli A, Paillot R, Broglia A, Kohnle L, Baldinelli F, Van der Stede Y. Assessment of listing and categorisation of animal diseases within the framework of the Animal Health Law (Regulation (EU) No 2016/429): infection with Equine Herpesvirus-1. EFSA J 2022 Jan;20(1):e07036.
    doi: 10.2903/j.efsa.2022.7036pubmed: 35035581google scholar: lookup
  5. Samoilowa S, Giessler KS, Torres CEM, Hussey GS, Allum A, Fux R, Jerke C, Kiupel M, Matiasek K, Sledge DG, Goehring LS. Equid herpesvirus-1 Distribution in Equine Lymphoid and Neural Tissues 70 Days Post Infection. Pathogens 2021 Jun 5;10(6).
    doi: 10.3390/pathogens10060707pubmed: 34198884google scholar: lookup
  6. Kirmse L, Thieme K, Doherr MG, Eule JC. Evaluation of Laboratory Techniques for the Diagnosis of Leptospira-Associated Equine Recurrent Uveitis (ERU) With Focus on the Goldmann-Witmer Coefficient. Vet Ophthalmol 2026 Jan;29(1):e70132.
    doi: 10.1111/vop.70132pubmed: 41518147google scholar: lookup
  7. Countrymann K, Ruby R, Miller AD. A retrospective study of 171 cases of equine meningoencephalomyelitis in the United States, 1996-2023. J Vet Diagn Invest 2026 Jan;38(1):100-111.
    doi: 10.1177/10406387251362241pubmed: 40988382google scholar: lookup
  8. El Brini Z, Cullinane A, Garvey M, Fassi Fihri O, Fellahi S, Amraoui F, Loutfi C, Sebbar G, Paillot R, Piro M. First Molecular and Phylogenetic Characterization of Equine Herpesvirus-1 (EHV-1) and Equine Herpesvirus-4 (EHV-4) in Morocco. Animals (Basel) 2025 Jan 5;15(1).
    doi: 10.3390/ani15010102pubmed: 39795045google scholar: lookup
  9. Lunn DP, Burgess BA, Dorman DC, Goehring LS, Gross P, Osterrieder K, Pusterla N, Soboll Hussey G. Updated ACVIM consensus statement on equine herpesvirus-1. J Vet Intern Med 2024 May-Jun;38(3):1290-1299.
    doi: 10.1111/jvim.17047pubmed: 38497217google scholar: lookup
  10. Soboll-Hussey G, Dorman DC, Burgess BA, Goehring L, Gross P, Neinast C, Osterrieder K, Pusterla N, Lunn DP. Relationship between equine herpesvirus-1 viremia and abortion or equine herpesvirus myeloencephalopathy in domesticated horses: A systematic review. J Vet Intern Med 2024 May-Jun;38(3):1872-1891.
    doi: 10.1111/jvim.16948pubmed: 38069576google scholar: lookup