Peste des Petits Ruminants Virus in Tibet, China
Figure 2. Phylogenetic relationship between peste des petits ruminants virus (PPRV) detected in Tibet, China, in 2007 and other virus isolates. PPRV strains sequenced in this study are highlighted in gray. Other sequences are from GenBank. Phylogenetic analyses were completed with MEGA 3.1 software that used a neighbor-joining algorithm and absolute distances and that followed 1,000 bootstrap replicates. The RBOK vaccine strain of rinderpest virus was included as an outgroup. The tree is based on the partial sequence of the fusion (F) protein gene (A) and the nucleocapsid (N) protein gene (B). Different classifications were used for the phylogenetic comparisons for the West African lineages 1 and 2. Nigeria and related strains have been classified as lineage 1; the Côte d’Ivoire and related strains have been classified as lineage 2 (1). Later research reversed this order in classifying the lineages in N gene analyses (2).