Emergence of antigenic variants within serotype A FMDV in the Middle East with antigenically critical amino acid substitutions

Vaccine. 2016 Jun 8;34(27):3199-3206. doi: 10.1016/j.vaccine.2016.02.057. Epub 2016 Mar 24.

Abstract

A new immunologically distinct strain (A-Iran-05) of foot-and-mouth disease virus serotype A emerged in the Middle East in 2003 that replaced the previously circulating strains (A-Iran-96 and A-Iran-99) in the region. This resulted in introduction of a new vaccine of this strain (A/TUR/2006) in 2006. Though this vaccine strain has been predominantly used to control FMD in the region, recent viruses isolated in 2012 and 2013 have shown antigenic drift and a poor match with it. In this study, we report the antigenic matching results and capsid sequence data of currently circulating viruses belonging to the SIS-10 and SIS-12 sub-lineages of A-Iran-05 (isolated in 2012 and 2013), highlighting the inadequacy of the currently used serotype A vaccines. Implications of these results in the context of FMD control in the Middle East are discussed.

Keywords: Antigenic determinants; Antigenic variation; Capsid sequence; Epitopes; FMD virus; Polyclonal antibodies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antibodies, Neutralizing / immunology
  • Antigenic Variation*
  • Antigens, Viral / immunology*
  • Capsid Proteins / immunology*
  • Cattle
  • Cross Reactions
  • Foot-and-Mouth Disease / prevention & control
  • Foot-and-Mouth Disease Virus / immunology*
  • Immune Sera / immunology
  • Middle East
  • Neutralization Tests
  • Protein Structure, Tertiary
  • Serogroup

Substances

  • Antibodies, Neutralizing
  • Antigens, Viral
  • Capsid Proteins
  • Immune Sera