Phylogenetic analysis based on the full coding sequences of Alphavirus isolated in China together with those referred in this review. Phylogenetic analyses were performed by the neighbor-joining method with MEGA software http://www.megasoftware.net/. Bootstrap probabilities of each node were calculated with 1,000 replicates. Scale bars indicate a genetic distance of 0.05-nt substitutions per site. The Chinese isolates are all shown in boldface in red.