Molecular Epidemiology of Human Enterovirus 71 Strains and Recent Outbreaks in the Asia-Pacific Region: Comparative Analysis of the VP1 and VP4 Genes
Figure 1. An overview of the genetic relationships of human enterovirus 71 (HEV71) strains isolated from 1970 through 2002. Dendrogram showing the genetic relationships among 53 HEV71 strains based on the alignment of the complete VP4 gene sequence (nucleotide positions 744–950). Details of the HEV71 strains included in the dendrogram are provided in Appendix Tables 1 and 2. Branch lengths are proportional to the number of nucleotide differences. The bootstrap values in 1,000 pseudoreplicates for major lineages within the dendrogram are shown as percentages. The marker denotes a measurement of relative phylogenetic distance. The VP4 nucleotide sequence of coxsackie virus A16 (CA16) (29) was used as an outgroup in the analysis. *Denotes HEV71 isolates from fatal cases; †denotes HEV71 strains falling outside existing genogroup boundaries.