title: Potential of a sequence-based antigenic distance measure to indicate equine influenza vaccine strain efficacy.
abstract: The calculation of p(epitope) values, a sequence-based measure of antigenic distance between strains, was developed for human influenza. The potential to apply the p(epitope) value to equine influenza vaccine strain selection was assessed. There was a negative correlation between p(epitope) value and vaccine efficacy for pairs of vaccine and challenge strains used in cross-protection studies in ponies that just reached statistical significance (p=0.046) only if one pair of viruses was excluded from the analysis. Thus the p(epitope) value has potential to provide additional data to consider in the decision-making process for updating equine influenza vaccine strains. However, further work is required to define the epitopes of the equine H3N8 haemagglutinin protein recognised by equine antibodies, which could lead to refinement of the p(epitope) value calculation. Furthermore, other factors such as vaccine potency and virulence of circulating strains may also influence vaccine efficacy.
authors.affiliation: School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington LE12 5RD, UK. Electronic address: janet.daly@nottingham.ac.uk.
authors.forename: Janet M
authors.initials: JM
authors.lastname: Daly
authors.forename: Debra
authors.initials: D
authors.lastname: Elton
mesh_terms: D000818:Animals; D000956:Antigens, Viral / Q000235:genetics* / Q000276:immunology*; D056738:Cross Protection; D000939:Epitopes / Q000235:genetics / Q000276:immunology; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000235:genetics / Q000276:immunology; D006734:Horse Diseases / Q000517:prevention & control*; D006736:Horses; D053123:Influenza A Virus, H3N8 Subtype / Q000235:genetics / Q000276:immunology; D007252:Influenza Vaccines / Q000276:immunology*; D009976:Orthomyxoviridae Infections / Q000517:prevention & control*
chemical_list: D000956:Antigens, Viral; D000939:Epitopes; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D007252:Influenza Vaccines
keywords: Efficacy; Equine; Influenza; Vaccine