Phylogenetic tree of ORF1b HEV sequences in 8 HEV-infected alloHSCT recipients. Phylogenetic relation of 321 bp ORF1b region was calculated using maximum likelihood, Kimura's 2 parameter analysis with bootstrapping (n = 1000). Branch lengths are proportional to the evolutionary relationship between the sequences, and internodal confidence of >70% is depicted in the tree. Genbank accession numbers, country of origin (eg, The Netherlands [NL], United States of America [USA]), HEV study number (eg, HEV001), date of drawal (yyyymmdd), and alloHSCT recipients are indicated in the taxa (red text). No indication for a common origin or for nosocomial HEV transmission was found.