FIG. 2.

Maximum parsimony phylogenetic analysis of VEEV subtype IC isolates from the 1962–1964 and 1995 outbreaks. An outgroup comprised of subtype IE strains MenaII (14) and 68U201 (18) was used to root the tree, and additional subtype I viruses described previously (13–15, 33) were included in the analysis. All virus strains are denoted by VEEV subtype, followed by country abbreviation and year of isolation, followed by strain name. Numbers at the nodes represent bootstrap confidence indices based on 1,000 replicates. The bar represents the number of nucleotide changes in each horizontal branch.