Foot-and-mouth disease

Foot-and-mouth disease is an economically important, highly contagious, disease of cloven-hoofed animals characterized by the appearance of vesicles (blisters) on the feet and in and around the mouth. The causative agent, foot-and-mouth disease virus, was the first mammalian virus to be discovered. It has a ribonucleic acid (RNA) genome enclosed within a protein coat. The virus replicates very rapidly within the cytoplasm of cells. The RNA genome has to function both as a messenger RNA and as a template for RNA replication. The RNA encodes a single polyprotein which is processed, by virus-encoded proteases, to about 12 mature products which are required for virus replication and assembly. Some of these viral proteins modify host cell activities to block anti-virus defence systems. Thus, this small virus displays a remarkably complex array of biological activities.