Background: In 1996, the Ortho HCV Version 3.0 ELISA Test System (HCV 3.0 EIA) was licensed in the United States for donor screening but was neither mandated nor universally implemented. Data from two studies comparing the differential performance of HCV 3.0 EIA and HCV 2.0 EIA are presented. The first study evaluated the differential performance in a cross-section of screened whole-blood donors after implementation of HCV 3.0 EIA; the second study evaluated the differential performance of HCV 3.0 EIA in plasma donors acutely infected with HCV, identified during routine Abbott HCV 2.0 EIA and HCV NAT (using Roche Ampliscreen plate assay) donor screening.
Study design and methods: The first study evaluated HCV 3.0 EIA repeat-reactive donations from four US blood centers, identified during the first 5 months of HCV 3.0 EIA implementation. HCV EIA repeat-reactive donations confirmed by RIBA HCV 3.0 SIA were retested using both Ortho HCV Version 2.0 ELISA Test System and Abbott HCV 2.0 EIA. All EIA-discordant donations were tested by polymerase chain reaction (PCR). In the second study, Abbott HCV 2.0 EIA-nonreactive, HCV PCR-positive donors were enrolled in a follow-up study in which the index and follow-up samples were re-evaluated by HCV 3.0 EIA.
Results: In the first study, of 292,459 donations, 501 (0.17%) confirmed HCV 3.0 EIA-reactive donations were identified; 15 (0.005%) were nonreactive by Ortho HCV 2.0 EIA and were all HCV RNA negative. In the second study, Ortho HCV 3.0 EIA retesting of Abbott HCV 2.0 EIA-nonreactive, RNA-positive index donations identified 16 (23%) as 3.0 EIA reactive. In 42 panels with a discordant time of seroconversion, HCV 3.0 EIA sero-conversion preceded HCV 2.0 EIA in all cases (p < 0.001). Two donors with HCV 3.0 EIA-reactive index donations never seroconverted by HCV 2.0 EIA during 160 to 180 days of follow-up.
Conclusion: These studies demonstrate that HCV 3.0 EIA compared to HCV 2.0 EIA can better detect 1) remote nonviremic HCV infections, 2) acute infection, and 3) HCV antibodies in cases of atypical seroconversion.