Evolution and molecular epidemiology of foot-and-mouth disease virus in China

Foot-and-mouth disease (FMD), caused by foot-and-mouth disease virus (FMDV), is considered one of the most important viral diseases of cloven-hoofed animals, causing severe economic losses in affected regions of the world. Three serotypes (A, O, and Asia 1) of FMDV have been identified in China since 1958. In addition, the occurrence of novel subtypes within these serotypes has made the epidemiology of FMDV more complicated over the last few years. In this review, we summarize the history and the current epidemiological situation in China, genetic diversity (e.g., quasispecies dynamics, antigenic heterogeneity, and functional constraints), intertypic recombination, and the evidence for positive selection of different FMDV serotypes. We also assess these genetic data to understand the origin, evolution, and transmission of FMDV, the findings of which may be useful in developing control measures for future epidemics.