title: Relevance of RIBA-3 supplementary test to HCV PCR positivity and genotypes for HCV confirmation of blood donors.
abstract: HCV antibody screening of 624,910 blood donations resulted in 3,832 samples being referred for confirmation. All were tested by RIBA-3 with 2,710 negative, 945 indeterminate and 177 positive results. HCV RNA was detected by PCR in an average of 69.5% of RIBA-3 positives (4 bands 84.1%; 3 bands 74.1%; 2 bands 34.1%) and only 0.53% of RIBA-3 indeterminates. Eighty-four percent of samples with a total RIBA-3 band intensity score (maximum 16) of > or = 8 were PCR positive compared with only 22% of those with a score of < 8. Total mean band intensities for HCV genotype 1 samples (n = 65) were 13.2, genotype 2 (n = 17) 11.4 and genotype 3 (n = 65) 11.2 with type 1 samples showing greater reactivity with c100 and c33 antibodies. No PCR positive type 1 samples were found with RIBA-3 total band scores less than 8, no PCR positive type 2 samples less than 6, whilst PCR positive type 3 samples were found with scores as low as 2. NS5 indeterminates were the most common (40.2%) single band pattern but yielded no PCR positive samples, followed by c33 (23.3%) with one PCR positive and c100 (20.2%) with one PCR positive whilst c22 indeterminates were least common (16.3%) but included three PCR positive donors. All five RIBA-3 indeterminate PCR positive donors were type 3.
authors.affiliation: Regional Virus Laboratory, Ruchill Hospital, Glasgow.
authors.forename: B C
authors.initials: BC
authors.lastname: Dow
authors.forename: I
authors.initials: I
authors.lastname: Buchanan
authors.forename: H
authors.initials: H
authors.lastname: Munro
authors.forename: E A
authors.initials: EA
authors.lastname: Follett
authors.forename: F
authors.initials: F
authors.lastname: Davidson
authors.forename: L E
authors.initials: LE
authors.lastname: Prescott
authors.forename: P L
authors.initials: PL
authors.lastname: Yap
authors.forename: P
authors.initials: P
authors.lastname: Simmonds
mesh_terms: D001782:Blood Donors; D004279:DNA, Viral / Q000097:blood; D005838:Genotype; D016174:Hepacivirus / Q000235:genetics*; D006801:Humans; D015151:Immunoblotting / Q000379:methods*; D016133:Polymerase Chain Reaction / Q000379:methods*
chemical_list: D004279:DNA, Viral