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The Veterinary record2012; 172(8); 210; doi: 10.1136/vr-2012-100735

Challenges and proposed solutions for more accurate serological diagnosis of equine infectious anaemia.

Abstract: Serological diagnosis of equine infectious anaemia virus (EIAV) infections has depended mainly on the agar gel immunodiffusion test (AGIDT). This study documents the presence of EIAV genetic sequences in a number of persistently infected horses and mules whose serums were interpreted as negative/equivocal on AGIDT, but positive on more than one ELISA test and in immunoblot tests. Strategies designed to take advantage of the combined strengths of the ELISA and AGIDT are shown effective in a national surveillance program for EIA in Italy where 17 per cent (25/149) of the equids considered to be infected with EIAV on combined/comparative serological data had reactions in the AGIDT that were interpreted as negative or equivocal. These data document the benefits of using a three-tiered laboratory system for the diagnosis of EIA. Although the ELISA-first strategy introduces some confusing results, the discovery of up to 20 per cent more cases of EIA makes it compelling. In our opinion, it is better and more defensible to find two samples in 1000 with resolvable but falsely positive ELISA tests for EIA than to release two to three horses in 10,000 with falsely negative test results for EIA (the rates seen in the Italian surveillance presented here).
Publication Date: 2012-11-16 PubMed ID: 23161812PubMed Central: PMC3593188DOI: 10.1136/vr-2012-100735Google Scholar: Lookup
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  • Journal Article

Summary

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The research article focuses on improving the accuracy of diagnosing equine infectious anaemia virus (EIAV) in horses and mules through an enhanced diagnostic approach combining both ELISA (Enzyme-Linked Immunosorbent Assay) tests and AGIDT (Agar Gel Immunodiffusion Test). They found that certain equines tested negative or equivocal on AGIDT, despite being infected, but tested positive in ELISA tests. The study advocates for a three-tiered diagnostic approach, despite the introduction of some confusing results, for detecting up to 20% more cases of EIAV.

Equine Infectious Anaemia and Diagnostic Techniques

  • The research study deals with the diagnosis of equine infectious anaemia virus, a persistent and occasionally fatal viral disease in horses, mules, and other equines.
  • The traditional method of diagnosing EIAV is through the agar gel immunodiffusion test (AGIDT), a serological test that utilizes antibodies for detection.
  • However, the study reveals that AGIDT, though commonly used, may not always provide accurate or complete results, as some infected equines were found to be negative or equivocal in the test.
  • The observational discrepancy lead to exploration of more sensitive testing methods, such as the Enzyme-Linked Immunosorbent Assay (ELISA) and immunoblot tests, which have shown positive results for the same set of equines.

Efficacy of Combined Diagnostic Blueprint

  • The combined diagnostic strategy inclusive of ELISA and AGIDT has been utilized effectively in a national surveillance program for EIA in Italy.
  • The research highlights that 17 per cent of the equids, deemed to be infected with EIAV based on combined/comparitive serological data, had reactions in the AGIDT that were interpreted as negative or equivocal.
  • This data builds the case for the benefits of a three-tiered laboratory system for EIA diagnosis. This integrated approach aids in more comprehensive and precise diagnosis of EIAV.
  • Notably, about 20 per cent more cases of EIA were discovered through this approach, making it a highly compelling method.

Acceptance of False Positives over False Negatives

  • Interestingly, the research mentions that using an ELISA-first strategy might introduce some confusing or false positive results.
  • The researchers argue, however, it’s more acceptable to discover two samples in 1000 with resolvable, yet false positives for EIA, than releasing two to three horses in 10,000 that are actually infected, but test falsely negative—an occurrence noted in the Italian surveillance program.
  • Essentially, the research encourages erring on the side of caution in detecting EIAV, to prevent the potential spread of this harmful virus. And to opt for further investigations in case of any doubts rather than risking the release of a truly infected horse.

Cite This Article

APA
Issel CJ, Scicluna MT, Cook SJ, Cook RF, Caprioli A, Ricci I, Rosone F, Craigo JK, Montelaro RC, Autorino GL. (2012). Challenges and proposed solutions for more accurate serological diagnosis of equine infectious anaemia. Vet Rec, 172(8), 210. https://doi.org/10.1136/vr-2012-100735

Publication

ISSN: 2042-7670
NlmUniqueID: 0031164
Country: England
Language: English
Volume: 172
Issue: 8
Pages: 210

Researcher Affiliations

Issel, C J
  • Department of Veterinary Science, Gluck Equine Research Center, University of Kentucky, Lexington KY, USA. cissel@uky.edu
Scicluna, M T
    Cook, S J
      Cook, R F
        Caprioli, A
          Ricci, I
            Rosone, F
              Craigo, J K
                Montelaro, R C
                  Autorino, G L

                    MeSH Terms

                    • Animals
                    • Enzyme-Linked Immunosorbent Assay / veterinary
                    • Equine Infectious Anemia / blood
                    • Equine Infectious Anemia / diagnosis
                    • False Negative Reactions
                    • Horses
                    • Immunoblotting / veterinary
                    • Immunodiffusion / veterinary
                    • Infectious Anemia Virus, Equine / isolation & purification
                    • Italy
                    • Population Surveillance / methods

                    References

                    This article includes 28 references
                    1. Cappelli K, Capomaccio S, Cook FR, Felicetti M, Marenzoni ML, Coppola G, Verini-Supplizi A, Coletti M, Passamonti F. Molecular detection, epidemiology, and genetic characterization of novel European field isolates of equine infectious anemia virus.. J Clin Microbiol 2011 Jan;49(1):27-33.
                      pmc: PMC3020406pubmed: 21084503doi: 10.1128/jcm.01311-10google scholar: lookup
                    2. Coggins L, Norcross NL. Immunodiffusion reaction in equine infectious anemia.. Cornell Vet 1970 Apr;60(2):330-5.
                      pubmed: 4986043
                    3. Coggins L, Norcross NL, Kemen MJ. The technique and application of the immunodiffusion test for equine infectious anemia. In: Equine Infectious Diseases III, Paris, France, July 17–21, 1972, pp 189–198.
                    4. Coggins L, Norcross NL, Nusbaum SR. Diagnosis of equine infectious anemia by immunodiffusion test.. Am J Vet Res 1972 Jan;33(1):11-8.
                      pubmed: 4333633
                    5. Coggins L, Patten V. Immunodiffusion test for equine infectious anemia. Proceedings of the Annual Meeting of the United States Animal Health Association 75, 254–261.
                    6. Cook RF, Cook SJ, Li FL, Montelaro RC, Issel CJ. Development of a multiplex real-time reverse transcriptase-polymerase chain reaction for equine infectious anemia virus (EIAV).. J Virol Methods 2002 Aug;105(1):171-9.
                      pubmed: 12176154doi: 10.1016/s0166-0934(02)00101-5google scholar: lookup
                    7. Craigo JK, Durkin S, Sturgeon TJ, Tagmyer T, Cook SJ, Issel CJ, Montelaro RC. Immune suppression of challenged vaccinates as a rigorous assessment of sterile protection by lentiviral vaccines.. Vaccine 2007 Jan 15;25(5):834-45.
                    8. Craigo JK, Leroux C, Howe L, Steckbeck JD, Cook SJ, Issel CJ, Montelaro RC. Transient immune suppression of inapparent carriers infected with a principal neutralizing domain-deficient equine infectious anaemia virus induces neutralizing antibodies and lowers steady-state virus replication.. J Gen Virol 2002 Jun;83(Pt 6):1353-1359.
                      pubmed: 12029150doi: 10.1099/0022-1317-83-6-1353google scholar: lookup
                    9. Craigo JK, Zhang B, Barnes S, Tagmyer TL, Cook SJ, Issel CJ, Montelaro RC. Envelope variation as a primary determinant of lentiviral vaccine efficacy.. Proc Natl Acad Sci U S A 2007 Sep 18;104(38):15105-10.
                      pmc: PMC1986620pubmed: 17846425doi: 10.1073/pnas.0706449104google scholar: lookup
                    10. Egberink HF, Ederveen J, Montelaro RC, Pedersen NC, Horzinek MC, Koolen MJ. Intracellular proteins of feline immunodeficiency virus and their antigenic relationship with equine infectious anaemia virus proteins.. J Gen Virol 1990 Mar;71 ( Pt 3):739-43.
                      pubmed: 1690264doi: 10.1099/0022-1317-71-3-739google scholar: lookup
                    11. Grund CH, Lechman ER, Issel CJ, Montelaro RC, Rushlow KE. Lentivirus cross-reactive determinants present in the capsid protein of equine infectious anaemia virus.. J Gen Virol 1994 Mar;75 ( Pt 3):657-62.
                      pubmed: 7510329doi: 10.1099/0022-1317-75-3-657google scholar: lookup
                    12. Harrold SM, Cook SJ, Cook RF, Rushlow KE, Issel CJ, Montelaro RC. Tissue sites of persistent infection and active replication of equine infectious anemia virus during acute disease and asymptomatic infection in experimentally infected equids.. J Virol 2000 Apr;74(7):3112-21.
                    13. Hines R, Maury W. DH82 cells: a macrophage cell line for the replication and study of equine infectious anemia virus.. J Virol Methods 2001 Jun;95(1-2):47-56.
                      pubmed: 11377712doi: 10.1016/s0166-0934(01)00288-9google scholar: lookup
                    14. Issel CJ, Adams WV Jr. Detection of equine infectious anemia virus in a horse with an equivocal agar gel immunodiffusion test reaction.. J Am Vet Med Assoc 1982 Feb 1;180(3):276-8.
                      pubmed: 6276354
                    15. Issel CJ, Cook RF. A review of techniques for the serologic diagnosis of equine infectious anemia.. J Vet Diagn Invest 1993 Jan;5(1):137-41.
                      pubmed: 8385498doi: 10.1177/104063879300500136google scholar: lookup
                    16. Issel CJ, Cook SJ, Cook RF, Cordes TR. Optimal paradigms to detect reservoirs of equine infectious anemia virus (EIAV). Journal of Equine Veterinary Science 19, 728–732.
                    17. Issel CJ, Rwambo PM, Montelaro RC. Evolution of equine infectious anemia diagnostic tests: recognition of a need for detection of anti-EIAV glycoprotein antibodies. In: Equine Infectious Diseases V, Lexington, KY, October 7–10, 1987, pp 196–200.
                    18. Langemeier JL, Cook SJ, Cook RF, Rushlow KE, Montelaro RC, Issel CJ. Detection of equine infectious anemia viral RNA in plasma samples from recently infected and long-term inapparent carrier animals by PCR.. J Clin Microbiol 1996 Jun;34(6):1481-7.
                    19. Li F, Craigo JK, Howe L, Steckbeck JD, Cook S, Issel C, Montelaro RC. A live attenuated equine infectious anemia virus proviral vaccine with a modified S2 gene provides protection from detectable infection by intravenous virulent virus challenge of experimentally inoculated horses.. J Virol 2003 Jul;77(13):7244-53.
                    20. Li F, Puffer BA, Montelaro RC. The S2 gene of equine infectious anemia virus is dispensable for viral replication in vitro.. J Virol 1998 Oct;72(10):8344-8.
                    21. Matsushita T, Hesterberg LK, Porter JP, Smith BJ, Newman LE. Comparison of diagnostic tests for the detection of equine infectious anemia antibody.. J Vet Diagn Invest 1989 Jan;1(1):50-2.
                      pubmed: 2562211doi: 10.1177/104063878900100114google scholar: lookup
                    22. Mcconnell S, Katada M, Darnton SM. Occult equine infectious anemia in an immunosuppressed serologically negative mare. Equine Practice 5, 32–36, 39.
                    23. Mcconnico RS, Floyd CF, Issel CJ, Lehenbauer TW, Rodgers S, Saliki JT. Evaluation of techniques for the serological diagnosis of equine infectious anaemia in a subclinically infected herd of reproductively active horses. In: Equine Infectious Diseases VIII, Dubai, March 23–26, 1998, p 400.
                    24. Montagnier L, Dauguet C, Axler CEA. A new type of retrovirus isolated from patients presenting with lymphadenopathy and acquired immune deficiency syndrome: structural and antigenic relatedness with equine infectious anaemia virus. Annales de Virologie 135E, 119–134.
                    25. Nagarajan MM, Simard C. Detection of horses infected naturally with equine infectious anemia virus by nested polymerase chain reaction.. J Virol Methods 2001 May;94(1-2):97-109.
                      pubmed: 11337044doi: 10.1016/s0166-0934(01)00283-xgoogle scholar: lookup
                    26. OIE. OIE Manual of Diagnostic Tests and Vaccines for Terrestrial Animals. p 1343.
                    27. Quinlivan M, Cook RF, Cullinane A. Real-time quantitative RT-PCR and PCR assays for a novel European field isolate of equine infectious anaemia virus based on sequence determination of the gag gene.. Vet Rec 2007 May 5;160(18):611-8.
                      pubmed: 17483378doi: 10.1136/vr.160.18.611google scholar: lookup
                    28. Toma B. Reponse serologique negative persistante chez une jument infectee par le virus de l'anemie infectieuse des equides [Persistent negative serological response in a mare infected with equine infectious anaemia virus]. Recueil de Medecine Veterinaire 156, 55–63.

                    Citations

                    This article has been cited 10 times.
                    1. Hu Z, Guo K, Du C, Sun J, Naletoski I, Chu X, Lin Y, Wang X, Barrandeguy M, Samuel M, Wang W, Lau PI, Wernery U, Raghavan R, Wang X. Development and evaluation of a blocking ELISA for serological diagnosis of equine infectious anemia. Appl Microbiol Biotechnol 2023 May;107(10):3305-3317.
                      doi: 10.1007/s00253-023-12504-5pubmed: 37039847google scholar: lookup
                    2. Câmara RJF, Bueno BL, Resende CF, Balasuriya UBR, Sakamoto SM, Reis JKPD. Viral Diseases that Affect Donkeys and Mules. Animals (Basel) 2020 Nov 25;10(12).
                      doi: 10.3390/ani10122203pubmed: 33255568google scholar: lookup
                    3. de Pablo-Maiso L, Doménech A, Echeverría I, Gómez-Arrebola C, de Andrés D, Rosati S, Gómez-Lucia E, Reina R. Prospects in Innate Immune Responses as Potential Control Strategies against Non-Primate Lentiviruses. Viruses 2018 Aug 17;10(8).
                      doi: 10.3390/v10080435pubmed: 30126090google scholar: lookup
                    4. Higgins SN, Howden KJ, James CR, Epp T, Lohmann KL. A retrospective study of owner-requested testing as surveillance for equine infectious anemia in Canada (2009-2012). Can Vet J 2017 Dec;58(12):1294-1300.
                      pubmed: 29203939
                    5. Nardini R, Autorino GL, Issel CJ, Cook RF, Ricci I, Frontoso R, Rosone F, Scicluna MT. Evaluation of six serological ELISA kits available in Italy as screening tests for equine infectious anaemia surveillance. BMC Vet Res 2017 Apr 14;13(1):105.
                      doi: 10.1186/s12917-017-1007-6pubmed: 28410613google scholar: lookup
                    6. Cruz F, Fores P, Ireland J, Moreno MA, Newton R. Freedom from equine infectious anaemia virus infection in Spanish Purebred horses. Vet Rec Open 2015;2(1):e000074.
                      doi: 10.1136/vetreco-2014-000074pubmed: 26392894google scholar: lookup
                    7. Ostuni A, Frontoso R, Crudele MA, Barca L, Amati M, Boni R, De Vendel J, Raimondi P, Bavoso A. Comparative Evaluation of a Multistrain Indirect ELISA Targeting Anti- p26 and gp45 Antibodies for EIAV Detection. Pathogens 2025 Jun 8;14(6).
                      doi: 10.3390/pathogens14060575pubmed: 40559583google scholar: lookup
                    8. Carvelli A, Nardini R, Carnio A, Ricci I, Rosone F, Sala M, Simeoni S, Maccarone D, Scicluna MT. Equine Infectious Anaemia: The Active Surveillance of an Entire Equid Population Reduces the Occurrence of the Infection. Transbound Emerg Dis 2024;2024:3439871.
                      doi: 10.1155/2024/3439871pubmed: 40303092google scholar: lookup
                    9. Domínguez-Odio A, González LIC, Alfonso DM, Guevara-Hernández F, La O Arias MA, Zayas MP, Ríos MÁB. Serodiagnosis of equine infectious anemia by indirect ELISA based on a novel synthetic peptide derived from gp45 glycoprotein. Vet Res Commun 2025 Apr 22;49(3):174.
                      doi: 10.1007/s11259-025-10707-xpubmed: 40261479google scholar: lookup
                    10. Zhang Z, Guo K, Chu X, Liu M, Du C, Hu Z, Wang X. Development and evaluation of a test strip for the rapid detection of antibody against equine infectious anemia virus. Appl Microbiol Biotechnol 2024 Dec;108(1):85.
                      doi: 10.1007/s00253-023-12980-9pubmed: 38189948google scholar: lookup