Figure S1 - Pathogenicity and Transmissibility of North American Triple Reassortant Swine Influenza A Viruses in Ferrets

Phylogenetic tree of the A) HA and B) NA gene segments based on nucleotide sequences from GenBank. Evolutionary history was inferred by using the neighbor-joining method. The percentage of replicate trees in which the associated taxa clustered in the bootstrap test (500 replicates) are shown next to the branches. Only bootstrap values >60 are shown. The tree is drawn to scale, with branch lengths indicating the evolutionary distances used to infer the phylogenetic tree. The evolutionary distances (the number of base substitutions per site) were computed by using the Kimura 2-parameter method. All ambiguous positions were removed for each sequence pair (pairwise deletion option). Evolutionary analyses were conducted by using the MEGA5 program. sw, swine; Eu sw, Eurasian avian-like swine; hu, human; pan, pandemic. •, Viruses used in this study.
(EPS)