Isolated HXHV virus having the following characteristics: (i) a DNA genome which is at least partially single-stranded, (ii) the said genome comprises one reading frame (ORF) encoding one protein or one polyprotein (iii) the said genome comprises a nucleotide sequence which exhibits, for any segment of at least 40 nucleotides belonging to the said sequence, at least 90% homology with SEQ ID NO: 1 or with its complementary sequence, nucleic material and peptide material and uses.