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Equine veterinary journal2019; 52(3); 420-427; doi: 10.1111/evj.13176

Multifocal outbreak of equine influenza in vaccinated horses in Argentina in 2018: Epidemiological aspects and molecular characterisation of the involved virus strains.

Abstract: Equine influenza is an important cause of respiratory disease of horses worldwide. The equine influenza virus (EIV) undergoes antigenic drift through the accumulation of amino acid substitutions in the viral proteins, which may lead to vaccine breakdown. Objective: To describe the epidemiological findings and the molecular characteristics of the EIV detected during the multifocal outbreak that occurred in Argentina between March and July 2018 and evidence a vaccine breakdown. Methods: Observational, descriptive study. Methods: Virus was detected in nasopharyngeal swabs using real-time reverse transcriptase PCR (RT-PCR). Nucleotide and deduced amino acid sequences of the haemagglutinin (HA) and neuraminidase (NA) genes were obtained from EIV positive nasopharyngeal swabs, and phylogenetic analysis was undertaken. Amino acid sequences were compared against the current World Organisation for Animal Health (OIE)-recommended Florida clade 1 vaccine strain and strain components of vaccines used in Argentina. Serum samples were tested using haemagglutination inhibition test. Results: Equine influenza virus infection was confirmed using real-time RT-PCR and serological testing. The phylogenetic analysis of the HA and NA genes revealed that all the EIV identified during the outbreak belong to the H3N8 subtype, Florida clade 1. Multiple amino acid changes, some of them at antigenic sites, were observed in the circulating virus when compared with the strains included in the most commonly used vaccine in Argentina. Seventy-six percent of the affected horses had been vaccinated with this vaccine, suggesting the occurrence of vaccine breakdown. Conclusions: The study does not include antigenic characterisation and full genome sequencing of Argentinian strains, that could provide additional information. Conclusions: The occurrence of this multifocal equine influenza outbreak in regularly vaccinated horses is a field evidence of vaccine breakdown, reinforcing the necessity of keeping vaccine strains updated according to OIE recommendations. It also underlines the importance of the implementation of appropriate quarantine measures and restriction of horse movement in the face of disease.
© 2019 EVJ Ltd.
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Publication Date: 2019-10-04 PubMed ID: 31494962DOI: 10.1111/evj.13176Google Scholar: Lookup
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  • Journal Article
  • Observational Study
  • Veterinary

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 research discusses a major outbreak of equine influenza in horses in Argentina in 2018, focusing on an epidemiological study and molecular characterisation of the strains involved. Despite widespread immunisation, a high percentage of vaccinated horses were affected, suggestive of potential issues with the vaccine.

Research Objective and Methodology

  • The goal of this study was to understand the epidemiological aspects and molecular characteristics of the equine influenza virus (EIV) during the large-scale outbreak that took place in Argentina from March to July 2018.
  • To identify the virus, real-time reverse transcriptase PCR (RT-PCR) was applied to nasopharyngeal swabs taken from the horses.
  • The researchers carried out phylogenetic analysis on the nucleotide and deduced amino acid sequences of the haemagglutinin (HA) and neuraminidase (NA) genes from the EIV positive swabs.
  • They compared the amino acid sequences against the current OIE (World Organisation for Animal Health)-recommended Florida clade 1 vaccine strain and other strains used in Argentinean vaccines.
  • Serum samples from the horses were tested using the haemagglutination inhibition test to confirm the presence of EIV infection.

Results of the Research

  • The study confirmed the presence of EIV infection in the horses using the real-time RT-PCR technique and serological testing.
  • According to the phylogenetic analysis, all the identified EIV belonged to the H3N8 subtype, Florida clade 1.
  • There were multiple alterations in the amino acid sequence in the circulating virus when compared with the strains in the most commonly administered vaccine in Argentina.
  • Despite being vaccinated with this vaccine, seventy-six percent of the affected horses were infected, thereby indicating a potential vaccine breakdown.

Conclusions

  • The study is limited in that it does not include antigenic characterisation and full genome sequencing of the Argentinian strains, which could add more insight to the findings.
  • However, the findings of the research highlight the problem of a vaccine breakdown, emphasising the need for ongoing updates of vaccine strains, in line with OIE recommendations.
  • The study also underscores the essential role of proper quarantine protocols and restrictions on horse movement to prevent the disease from spreading.

Cite This Article

APA
Olguin-Perglione C, Vissani MA, Alamos F, Tordoya MS, Barrandeguy M. (2019). Multifocal outbreak of equine influenza in vaccinated horses in Argentina in 2018: Epidemiological aspects and molecular characterisation of the involved virus strains. Equine Vet J, 52(3), 420-427. https://doi.org/10.1111/evj.13176

Publication

Equine veterinary journal
ISSN: 2042-3306
NlmUniqueID: 0173320
Country: United States
Language: English
Volume: 52
Issue: 3
Pages: 420-427

Researcher Affiliations

Olguin-Perglione, C
  • Instituto de Virología, Instituto Nacional de Tecnología Agropecuaria (INTA), Hurlingham, Buenos Aires, Argentina.
Vissani, M A
  • Instituto de Virología, Instituto Nacional de Tecnología Agropecuaria (INTA), Hurlingham, Buenos Aires, Argentina.
  • Escuela de Veterinaria, Universidad del Salvador, Pilar, Buenos Aires, Argentina.
Alamos, F
  • Instituto de Virología, Instituto Nacional de Tecnología Agropecuaria (INTA), Hurlingham, Buenos Aires, Argentina.
Tordoya, M S
  • Instituto de Virología, Instituto Nacional de Tecnología Agropecuaria (INTA), Hurlingham, Buenos Aires, Argentina.
Barrandeguy, M
  • Instituto de Virología, Instituto Nacional de Tecnología Agropecuaria (INTA), Hurlingham, Buenos Aires, Argentina.
  • Escuela de Veterinaria, Universidad del Salvador, Pilar, Buenos Aires, Argentina.

MeSH Terms

  • Animals
  • Argentina
  • Disease Outbreaks
  • Horse Diseases / epidemiology
  • Horse Diseases / virology
  • Horses
  • Influenza A Virus, H3N8 Subtype
  • Orthomyxoviridae Infections / epidemiology
  • Orthomyxoviridae Infections / veterinary
  • Phylogeny

Grant Funding

  • Instituto Nacional de Tecnología Agropecuaria (INTA)
  • INTA-Haras Agreement

References

This article includes 40 references
  1. Woodward AL, Rash AS, Blinman D, Bowman S, Chambers TM, Daly JM, Damiani A, Joseph S, Lewis N, McCauley JW, Medcalf L, Mumford J, Newton JR, Tiwari A, Bryant NA, Elton DM. Development of a surveillance scheme for equine influenza in the UK and characterisation of viruses isolated in Europe, Dubai and the USA from 2010 to 2012. Vet. Microbiol. 2014 169, 113-127.
  2. Cullinane A, Newton JR. Equine influenza - a global perspective. Vet. Microbiol. 2013 167, 205-214.
  3. Scholtens RG, Steele JH, Dowdle WR, Yarbrough WB, Robinson RQ. U.S. epizootic of equine influenza, 1963. Public Health Rep. 1964 79, 393-402.
  4. Waddell GH, Teigland MB, Sigel MM. A new influenza virus associated with equine respiratory disease. J. Am. Vet. Med. Assoc. 1963 143, 587-590.
  5. Daly JM, MacRae S, Newton JR, Wattrang E, Elton DM. Equine influenza: a review of an unpredictable virus. Vet. J. 2011 189, 7-14.
  6. Daly JM, Lai AC, Binns MM, Chambers TM, Barrandeguy M, Mumford JA. Antigenic and genetic evolution of equine H3N8 influenza A viruses. J. Gen. Virol. 1996 77, 661-671.
  7. Kawaoka Y, Bean WJ, Webster RG. Evolution of the hemagglutinin of equine H3 influenza viruses. Virology 1989 169, 283-292.
  8. Lai AC, Chambers TM, Holland RE Jr, Morley PS, Haines DM, Townsend HG, Barrandeguy M. Diverged evolution of recent equine-2 influenza (H3N8) viruses in the Western Hemisphere. Arch. Virol. 2001 146, 1063-1074.
  9. Gildea S, Quinlivan M, Arkins S, Cullinane A. The molecular epidemiology of equine influenza in Ireland from 2007 to 2010 and its international significance. Equine Vet. J. 2012 44, 387-392.
  10. Gildea S, Fitzpatrick DA, Cullinane A. Epidemiological and virological investigations of equine influenza outbreaks in Ireland (2010-2012). Influenza Other Respir. Viruses 2013 7 Suppl. 4, 61-72.
  11. Ito M, Nagai M, Hayakawa Y, Komae H, Murakami N, Yotsuya S, Asakura S, Sakoda Y, Kida H. Genetic analyses of an H3N8 influenza virus isolate, causative strain of the outbreak of equine influenza at the Kanazawa Racecourse in Japan in 2007. J. Vet. Med. Sci. 2008 70, 899-906.
  12. King E, Macdonald D. Report of the board of inquiry appointed by the board of the National Horseracing Authority to conduct enquiry into the causes of the equine influenza which started in the Western Cape in early December 2003 and spread to the Eastern Cape and Gauteng. Aust. Vet. J. 2004 23, 139-142.
  13. Perglione CO, Gildea S, Rimondi A, Mino S, Vissani A, Carossino M, Cullinane A, Barrandeguy M. Epidemiological and virological findings during multiple outbreaks of equine influenza in South America in 2012. Influenza Other Respir. Viruses 2016 10, 37-46.
  14. Watson J, Daniels P, Kirkland P, Carroll A, Jeggo M. The 2007 outbreak of equine influenza in Australia: lessons learned for international trade in horses. Rev. Sci. Tech. 2011 30, 87-93.
  15. Alves Beuttemmuller E, Woodward A, Rash AS, Dos Santos Ferraz LE, Fernandes Alfieri A, Alfieri AA, Elton D. Characterisation of the epidemic strain of H3N8 equine influenza virus responsible for outbreaks in South America in 2012. Virology J. 2016 13, 45.
  16. Favaro PF, Fernandes WR, Reischak D, Brandao PE, Silva SOS, Richtzenhain LJ. Evolution of equine influenza viruses (H3N8) during a Brazilian outbreak, 2015. Braz. J. Microbiol. 2018 49, 336-346.
  17. Yondon M, Heil GL, Burks JP, Zayat B, Waltzek TB, Jamiyan BO, McKenzie PP, Krueger WS, Friary JA, Gray GC. Isolation and characterization of H3N8 equine influenza A virus associated with the 2011 epizootic in Mongolia. Influenza Other Respir. Viruses 2013 7, 659-665.
  18. Virmani N, Bera BC, Singh BK, Shanmugasundaram K, Gulati BR, Barua S, Vaid RK, Gupta AK, Singh RK. Equine influenza outbreak in India (2008-09): virus isolation, sero-epidemiology and phylogenetic analysis of HA gene. Vet. Microbiol. 2010 143, 224-237.
  19. Qi T, Guo W, Huang WQ, Li HM, Zhao LP, Dai LL, He N, Hao XF, Xiang WH. Genetic evolution of equine influenza viruses isolated in China. Arch. Virol. 2010 155, 1425-1432.
  20. Barbic L, Madic J, Turk N, Daly J. Vaccine failure caused an outbreak of equine influenza in Croatia. Vet. Microbiol. 2009 133, 164-171.
  21. Gildea S, Garvey M, Lyons P, Lyons R, Gahan J, Walsh C, Cullinane A. Multifocal equine influenza outbreak with vaccination breakdown in thoroughbred racehorses. Pathogens 2018 7, E43.
  22. Cullinane A, Elton D, Mumford J. Equine influenza - surveillance and control. Influenza Other Respir. Viruses 2010 4, 339-344.
  23. . Expert surveillance panel on equine influenza vaccine composition - conclusions and recommendations. Office International des Epizooties Bulletin .
  24. . Resolución SENASA 521/2016. .
  25. Rash A, Woodward A, Bryant N, McCauley J, Elton D. An efficient genome sequencing method for equine influenza [H3N8] virus reveals a new polymorphism in the PA-X protein. Virol. J. 2014 11, 159.
  26. Hall TA. BioEdit: a user - friendly biological sequence alingment editor and analysis program for windows 95/98/NT. Nucl. Acid. Symp. 1999 41, 95-98.
  27. Guindon S, Dufayard JF, Lefort V, Anisimova M, Hordijk W, Gascuel O. New algorithms and methods to estimate maximum-likelihood phylogenies: assessing the performance of PhyML 3.0. Syst. Biol. 2010 59, 307-321.
  28. Posada D. jModelTest: phylogenetic model averaging. Mol. Biol. Evol. 2008 25, 1253-1256.
  29. . Chapter 2.5.7 Equine Influenza. Manual of Diagnostic Tests and Vaccines for Terrestrial Animals 2016 OIE, Paris, France. pp 1-16.
  30. . OIE-WAHID interface. World animale health information database. 2018.
  31. Shu Y, McCauley J. GISAID: global initiative on sharing all influenza data - from vision to reality. Euro Surveill. 2017 22.
  32. Gildea S, Arkins S, Cullinane A. Management and environmental factors involved in equine influenza outbreaks in Ireland 2007 - 2010. Equine Vet. J. 2011 43, 608-617.
  33. Bryant NA, Rash AS, Russell CA, Ross J, Cooke A, Bowman S, MacRae S, Lewis NS, Paillot R, Zanoni R, Meier H, Griffiths LA, Daly JM, Tiwari A, Chambers TM, Newton JR, Elton DM. Antigenic and genetic variations in European and North American equine influenza virus strains (H3N8) isolated from 2006 to 2007. Vet. Microbiol. 2009 138, 41-52.
  34. Mena J, Brito B, Moreira R, Tadich T, Gonzalez I, Cruces J, Ortega R, van Bakel H, Rathnasinghe R, Pizarro-Lucero J, Medina R, Neira V. Re-emergence of H3N8 equine influenza A virus in Chile, 2018. Transbound. Emerg. Dis. 2018 65, 1408-1415.
  35. . Resolucíon Dirección General de Servicios Ganaderos, No 131/018. 2018.
  36. Yates P, Mumford JA. Equine influenza vaccine efficacy: the significance of antigenic variation. Vet. Microbiol. 2000 74, 173-177.
  37. Daly JM, Murcia PR. Strategic implementation of vaccines for control of equine influenza. Equine Vet. J. 2018 50, 153-154.
  38. Yamanaka T, Niwa H, Tsujimura K, Kondo T, Matsumura T. Epidemic of equine influenza among vaccinated racehorses in Japan in 2007. J. Vet. Med. Sci. 2008 70, 623-625.
  39. Woodward A, Rash AS, Medcalf E, Bryant NA, Elton DM. Using epidemics to map H3 equine influenza virus determinants of antigenicity. Virology 2015 481, 187-198.
  40. Lewis NS, Daly JM, Russell CA, Horton DL, Skepner E, Bryant NA, Burke DF, Rash AS, Wood JL, Chambers TM, Fouchier RA, Mumford JA, Elton DM, Smith DJ. Antigenic and genetic evolution of equine influenza A (H3N8) virus from 1968 to 2007. J. Virol. 2011 85, 12742-12749.

Citations

This article has been cited 12 times.
  1. Yang Y, Guo K, Xu L, Guo W, Dong M, Liu W, Li S, Zhang Z, Chu X, Wang Y, Zhang Z, Hu Z, Wang X. Development and application of a NP-cELISA for the detection of nucleoprotein antibodies of equine influenza virus. Microbiol Spectr 2025 Oct 7;13(10):e0093925.
    doi: 10.1128/spectrum.00939-25pubmed: 40853243google scholar: lookup
  2. Gonzalez-Obando J, Jaimes-Dueñez J, Zuluaga-Cabrera A, Forero JE, Diaz A, Rojas-Arbeláez C, Ruiz-Saenz J. Seroprevalence of Equine Influenza Virus Antibodies in Horses from Four Localities in Colombia. Viruses 2025 Jul 16;17(7).
    doi: 10.3390/v17070999pubmed: 40733615google scholar: lookup
  3. Gonzalez-Obando J, Zuluaga-Cabrera A, Moreno I, Úsuga J, Ciuderis K, Forero JE, Diaz A, Rojas-Arbeláez C, Hernández-Ortiz JP, Ruiz-Saenz J. First Molecular Detection and Epidemiological Analysis of Equine Influenza Virus in Two Regions of Colombia, 2020-2023. Viruses 2024 May 24;16(6).
    doi: 10.3390/v16060839pubmed: 38932133google scholar: lookup
  4. Wasik BR, Rothschild E, Voorhees IEH, Reedy SE, Murcia PR, Pusterla N, Chambers TM, Goodman LB, Holmes EC, Kile JC, Parrish CR. Understanding the divergent evolution and epidemiology of H3N8 influenza viruses in dogs and horses. Virus Evol 2023;9(2):vead052.
    doi: 10.1093/ve/vead052pubmed: 37692894google scholar: lookup
  5. Gonzalez-Obando J, Forero JE, Zuluaga-Cabrera AM, Ruiz-Saenz J. Equine Influenza Virus: An Old Known Enemy in the Americas. Vaccines (Basel) 2022 Oct 14;10(10).
    doi: 10.3390/vaccines10101718pubmed: 36298583google scholar: lookup
  6. Alaql FA, Alhafufi AN, Kasem S, Alhammad YMO, Albaqshi H, Alyousaf A, Alsubaie FM, Alghamdi AN, Abdel-Moneim AS, Alharbi SA. Full-Length Genome of the Equine Influenza A Virus Subtype H3N8 from 2019 Outbreak in Saudi Arabia. Animals (Basel) 2022 Oct 10;12(19).
    doi: 10.3390/ani12192720pubmed: 36230462google scholar: lookup
  7. Pusterla N, James K, Barnum S, Bain F, Barnett DC, Chappell D, Gaughan E, Craig B, Schneider C, Vaala W. Frequency of Detection and Prevalence Factors Associated with Common Respiratory Pathogens in Equids with Acute Onset of Fever and/or Respiratory Signs (2008-2021). Pathogens 2022 Jul 2;11(7).
    doi: 10.3390/pathogens11070759pubmed: 35890002google scholar: lookup
  8. Oladunni FS, Oseni SO, Martinez-Sobrido L, Chambers TM. Equine Influenza Virus and Vaccines. Viruses 2021 Aug 20;13(8).
    doi: 10.3390/v13081657pubmed: 34452521google scholar: lookup
  9. Olguin-Perglione C, Barrandeguy ME. An Overview of Equine Influenza in South America. Viruses 2021 May 12;13(5).
    doi: 10.3390/v13050888pubmed: 34065839google scholar: lookup
  10. Reemers S, van Bommel S, Cao Q, Sutton D, van de Zande S. Protection against the New Equine Influenza Virus Florida Clade I Outbreak Strain Provided by a Whole Inactivated Virus Vaccine. Vaccines (Basel) 2020 Dec 21;8(4).
    doi: 10.3390/vaccines8040784pubmed: 33371484google scholar: lookup
  11. Wilson A, Pinchbeck G, Dean R, McGowan C. Equine influenza vaccination in the UK: Current practices may leave horses with suboptimal immunity. Equine Vet J 2021 Sep;53(5):1004-1014.
    doi: 10.1111/evj.13377pubmed: 33124070google scholar: lookup
  12. Cullinane A, Gahan J, Walsh C, Nemoto M, Entenfellner J, Olguin-Perglione C, Garvey M, Huang Fu TQ, Venner M, Yamanaka T, Barrandeguy M, Fernandez CJ. Evaluation of Current Equine Influenza Vaccination Protocols Prior to Shipment, Guided by OIE Standards. Vaccines (Basel) 2020 Feb 29;8(1).
    doi: 10.3390/vaccines8010107pubmed: 32121419google scholar: lookup
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