An oligomer combination for detecting a human parvovirus target nucleic acid and a hepatitis A virus target nucleic acid in a sample, said oligomer combination comprising: first and second amplification oligomers for amplifying a human parvovirus nucleic acid target region, wherein (a) the first parvovirus amplification oligomer comprises a first target-hybridizing sequence that is from 14 to 27 contiguous nucleotides contained in the sequence of SEQ ID NO: 181 and that includes at least the sequence of SEQ ID NO: 117, SEQ ID NO: 179 or SEQ ID NO: 180; and (b) the second parvovirus amplification oligomer comprises a second target- hybridizing sequence that is from 14 to 30 contiguous nucleotides contained in the sequence of SEQ ID NO: 189 and that includes at least the sequence of SEQ ID NO: 188; and first and second amplification oligomers for amplifying an HAV nucleic acid target region, wherein (a) the first HAV amplification oligomer comprises a first target-hybridizing sequence that is from 14 to 27 contiguous nucleotides contained in the sequence of SEQ ID NO: 174 and that includes at least the sequence of SEQ ID NO: 173; and (b) the second HAV amplification oligomer comprises a second target-hybridizing sequence that is from 14 to 30 contiguous nucleotides contained in the sequence of SEQ ID NO: 177 and that includes at least the sequence of SEQ ID NO: 175. first and second amplification oligomers for amplifying a human parvovirus nucleic acid target region, wherein (a) the first parvovirus amplification oligomer comprises a first target-hybridizing sequence that is from 14 to 27 contiguous nucleotides contained in the sequence of SEQ ID NO: 181 and that includes at least the sequence of SEQ ID NO: 117, SEQ ID NO: 179 or SEQ ID NO: 180; and (b) the second parvovirus amplification oligomer comprises a second target- hybridizing sequence that is from 14 to 30 contiguous nucleotides contained in the sequence of SEQ ID NO: 189 and that includes at least the sequence of SEQ ID NO: 188; and (a) the first parvovirus amplification oligomer comprises a first target-hybridizing sequence that is from 14 to 27 contiguous nucleotides contained in the sequence of SEQ ID NO: 181 and that includes at least the sequence of SEQ ID NO: 117, SEQ ID NO: 179 or SEQ ID NO: 180; and (b) the second parvovirus amplification oligomer comprises a second target- hybridizing sequence that is from 14 to 30 contiguous nucleotides contained in the sequence of SEQ ID NO: 189 and that includes at least the sequence of SEQ ID NO: 188; and first and second amplification oligomers for amplifying an HAV nucleic acid target region, wherein (a) the first HAV amplification oligomer comprises a first target-hybridizing sequence that is from 14 to 27 contiguous nucleotides contained in the sequence of SEQ ID NO: 174 and that includes at least the sequence of SEQ ID NO: 173; and (b) the second HAV amplification oligomer comprises a second target-hybridizing sequence that is from 14 to 30 contiguous nucleotides contained in the sequence of SEQ ID NO: 177 and that includes at least the sequence of SEQ ID NO: 175. (a) the first HAV amplification oligomer comprises a first target-hybridizing sequence that is from 14 to 27 contiguous nucleotides contained in the sequence of SEQ ID NO: 174 and that includes at least the sequence of SEQ ID NO: 173; and (b) the second HAV amplification oligomer comprises a second target-hybridizing sequence that is from 14 to 30 contiguous nucleotides contained in the sequence of SEQ ID NO: 177 and that includes at least the sequence of SEQ ID NO: 175.