Fig. 1.

Evolutionary relationships of taxa. Phylogenetic tree for a set of ORF2 HEV sequence of genotypes 1, 2, 3 and 4. Evolutionary history was inferred by the neighbour-joining method. The tree is drawn to scale, with branch lengths in the same units as those of the evolutionary distances used to infer the phylogenetic tree. Evolutionary distances were computed using the p-distance method and are in the units of the number of base differences per site. The analysis involved 38 nucleotide sequences; the six Italian wild boar–derived HEV sequences are circled. There were a total of 282 positions in the final data set. Evolutionary analyses were conducted in MEGA6 [21]. HEV, hepatitis E virus; ORF, open reading frame.