Comparing specificity and seroconversion sensitivity among major blood screening assays for human immunodeficiency virus and viral hepatitis.

BACKGROUND AND

OBJECTIVES

Accurate detection of transfusion-transmissible infections, such as human immunodeficiency virus (HIV) and hepatitis C and B viruses (HCV/HBV), is critical to ensure blood safety, and screening assays must demonstrate high specificity and sensitivity. In this study, we compared the performances of Elecsys® HIV Duo, HCV Duo, Anti-HCV II and HBsAg II immunoassays with those of comparator assays HIV Ag/Ab Combo, Anti-HCV II and HBsAg on the Alinity® s platform and HIV Ag/Ab Combo, Anti-HCV and HBsAg Qualitative II on the Alinity i platform.

MATERIALS AND

METHODS

Approximately 2050 plasma samples from first-time blood donors and commercial seroconversion panels were used. Specificity was assessed as the proportion of true non-reactive samples identified by each assay. Seroconversion sensitivity was evaluated based on the detection time and average interval from nucleic acid testing (NAT)-positivity to assay reactivity.

RESULTS

Overall, all Elecsys assays evaluated had similar specificities as the corresponding Alinity s/i assays, although the absolute difference in specificity between Alinity i Anti-HCV assay and the other HCV assays was statistically significant. The seroconversion sensitivities of Elecsys HIV Duo and HBsAg II assays were similar to the corresponding Alinity s/i assays. For HCV, Elecsys HCV Duo assay detected infection earlier than Alinity s/i assays for most panels (87.0% and 91.8%, respectively), with an average detection time from NAT positivity for HCV RNA of 1.5 days versus 21.4 and 23.8 days, respectively.

CONCLUSION

The robust specificities and early detection capabilities of the evaluated Elecsys assays support their routine use in blood donor screening and diagnosis.