Nine (3.4%) samples were positive. Comparison of PCR product sequences of these 9 isolates (GenBank accession nos. AM109958-AM109966) showed minor differences that occurred at 1 to 4 nucleotide positions, and a high level of sequence identity (99%-100%) was observed with the NP1 sequences of the previously identified ST1 and ST2 isolates (2) . This finding indicates that HBoV is a highly conserved virus.