Foot-and-Mouth Disease

Foot-and-mouth disease (FMD) is a highly infectious viral disease of domestic cloven-hoofed animals, including cattle, swine, goats, and sheep, as well as some species of wild animals. The viral agent, FMD virus (FMDV), is the type species of the Aphthovirus genus of the Picornaviridae family. The major consequence of FMD is a high degree of morbidity, including fever, lameness, and vesicular lesions on the tongue, feet, snout, and teats, but there is generally low mortality in infected animals except when the disease affects the young. Additional research with naturally susceptible animals is necessary to understand the mechanism of immunosuppression FMDV has developed and to identify the viral protein(s) that participates in this process. In addition to the high genetic variation, other mechanisms involving interaction of specific viral proteins or interactions of 5' and 3' untranslated regions (UTRs) with cellular targets have been shown to contribute to its virulence. In vitro studies have shown that after FMDV infection of BHK cells several proteins, including poly(A)-binding protein, polypyrimidine tract-binding protein (PTBP), and two subunits of the translation factor eIF3 (eIF3a and -b) undergo proteolytic cleavage. It is hoped that new information obtained from comprehensive viral pathogenesis studies will enable researchers to develop more effective disease control strategies, including induction of rapid protective responses to inhibit or at least limit the spread of this disease.