Recent Spread of a New Strain (A-Iran-05) of Foot-and-Mouth Disease Virus Type A in the Middle East

This report describes the characterization of a new genotype of foot-and-mouth disease virus (FMDV) type A responsible for recent FMD outbreaks in the Middle East. Initially identified in samples collected in 2003 from Iran, during 2005 and 2006 this FMDV lineage (proposed to be named A-Iran-05) spread into Saudi Arabia and Jordan and then further west into Turkey reaching European Thrace in January 2007. Most recently A-Iran-05 has been found in Bahrain. To the east of Iran, it has been recognized in Afghanistan (2004-07) and Pakistan (2006-07). Throughout the region, this lineage is now the predominant genotype of FMDV serotype A sampled, and has appeared to have replaced the A-Iran-96 and A-Iran-99 strains which were previously encountered. In August 2007, a new A-Iran-05 sub-lineage (which we have called A-Iran-05ARD⁻⁰⁷) was identified in Ardahan, Turkey, close to the border with Georgia. This new sub-lineage appeared to predominate in Turkey in 2008, but has, so far, not been identified in any other country. Vaccine matching tests revealed that the A-Iran-05 viruses are antigenically different to A-Iran-96 and more like A₂₂. These findings emphasize the importance of undertaking continued surveillance in the Middle East and Central Asia in order to detect and monitor the emergence and spread of new FMDV strains.