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Home / Equine Research Bank / J Virol / Antigenic and genetic evolution of equine influenza A (H3N8)...
Journal of virology2011; 85(23); 12742-12749; doi: 10.1128/JVI.05319-11

Antigenic and genetic evolution of equine influenza A (H3N8) virus from 1968 to 2007.

Abstract: Equine influenza virus is a major respiratory pathogen in horses, and outbreaks of disease often lead to substantial disruption to and economic losses for equestrian industries. The hemagglutinin (HA) protein is of key importance in the control of equine influenza because HA is the primary target of the protective immune response and the main component of currently licensed influenza vaccines. However, the influenza virus HA protein changes over time, a process called antigenic drift, and vaccine strains must be updated to remain effective. Antigenic drift is assessed primarily by the hemagglutination inhibition (HI) assay. We have generated HI assay data for equine influenza A (H3N8) viruses isolated between 1968 and 2007 and have used antigenic cartography to quantify antigenic differences among the isolates. The antigenic evolution of equine influenza viruses during this period was clustered: from 1968 to 1988, all isolates formed a single antigenic cluster, which then split into two cocirculating clusters in 1989, and then a third cocirculating cluster appeared in 2003. Viruses from all three clusters were isolated in 2007. In one of the three clusters, we show evidence of antigenic drift away from the vaccine strain over time. We determined that a single amino acid substitution was likely responsible for the antigenic differences among clusters.
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Publication Date: 2011-09-21 PubMed ID: 21937642PubMed Central: PMC3209411DOI: 10.1128/JVI.05319-11Google Scholar: Lookup
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  • Journal Article
  • Research Support
  • N.I.H.
  • Extramural
  • Research Support
  • Non-U.S. Gov't
  • Research Support
  • U.S. Gov't
  • Non-P.H.S.

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 article focuses on the changes and evolution of the Equine Influenza A (H3N8) virus over a period from 1968 to 2007, specifically in relation to the hemagglutinin (HA) protein which drives immune responses and informs vaccine design.

Objective of the Study

  • The study aimed to understand the antigenic and genetic evolution of the equine influenza A (H3N8) virus over forty years, specifically focusing on the changes in the HA protein. The HA protein is significant in controlling equine influenza as it is the primary target of defensive immune responses and is a crucial component of influenza vaccines.

Methodology of the Research

  • The researchers used the hemagglutination inhibition (HI) assay to assess antigenic drift, the alteration of the influenza virus HA protein over time.
  • They generated HI assay data for equine influenza A (H3N8) viruses isolated between 1968 and 2007.
  • Antigenic cartography was used to measure antigenic differences among the isolates.

Findings of the Study

  • The study found that the antigenic evolution of equine influenza viruses during these four decades occurred in clusters.
  • From 1968 to 1988, all isolates formed a single antigenic cluster, which then divided into two co-circulating clusters in 1989. A third co-circulating cluster appeared in 2003.
  • In 2007, viruses from all three clusters were isolated.
  • The study found evidence of antigenic drift in one of the clusters, indicating a movement away from the vaccine strain over time.
  • It was determined that a singular amino acid substitution was likely responsible for the antigenic differences among these clusters.

Implications of the Research

  • The study is essential to the understanding of the evolution of the equine influenza A (H3N8) virus, particularly in response to antigenic drift.
  • This understanding is vital for updating vaccine strains to ensure their effectiveness.
  • The findings may also aid in the prediction of future antigenic drifts, informing the development of future equine influenza vaccines.

Cite This Article

APA
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. (2011). Antigenic and genetic evolution of equine influenza A (H3N8) virus from 1968 to 2007. J Virol, 85(23), 12742-12749. https://doi.org/10.1128/JVI.05319-11

Publication

Journal of virology
ISSN: 1098-5514
NlmUniqueID: 0113724
Country: United States
Language: English
Volume: 85
Issue: 23
Pages: 12742-12749

Researcher Affiliations

Lewis, N S
  • Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, United Kingdom. nsl25@cam.ac.uk
Daly, J M
    Russell, C A
      Horton, D L
        Skepner, E
          Bryant, N A
            Burke, D F
              Rash, A S
                Wood, J L N
                  Chambers, T M
                    Fouchier, R A M
                      Mumford, J A
                        Elton, D M
                          Smith, D J

                            MeSH Terms

                            • Amino Acid Substitution
                            • Animals
                            • Antigens, Viral / classification
                            • Antigens, Viral / immunology
                            • Blotting, Western
                            • Cells, Cultured
                            • Dogs
                            • Evolution, Molecular
                            • Hemagglutination Inhibition Tests
                            • Hemagglutinin Glycoproteins, Influenza Virus / genetics
                            • Hemagglutinin Glycoproteins, Influenza Virus / immunology
                            • Hemagglutinins / immunology
                            • Hemagglutinins / metabolism
                            • Horses
                            • Influenza A Virus, H3N8 Subtype / genetics
                            • Influenza A Virus, H3N8 Subtype / immunology
                            • Influenza A Virus, H3N8 Subtype / isolation & purification
                            • Kidney / cytology
                            • Kidney / metabolism
                            • Kidney / virology
                            • Orthomyxoviridae Infections / genetics
                            • Orthomyxoviridae Infections / immunology
                            • Orthomyxoviridae Infections / virology
                            • Phylogeny
                            • RNA, Messenger / genetics
                            • RNA, Viral / genetics
                            • Reverse Transcriptase Polymerase Chain Reaction
                            • Time Factors

                            Grant Funding

                            • DP1 OD000490 / NIH HHS
                            • HHSN266200700010C / NIAID NIH HHS
                            • DP1-OD000490-01 / NIH HHS

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