Hepatitis C core antigen in Polish blood donors

BACKGROUND: The goal of this study was to evaluate the feasibility of adopting the HCV core antigen ELISA (HCVcAg) for routine screening of Polish blood donors. STUDY DESIGN AND METHODS: A total of 133,279 donor samples were tested by ORTHO HCVcAg. All repeatedly reactive (RR) samples were tested by neutralization test for confirmation, RIBA HCV for anti-HCV, and by Cobas Amplicore for HCV RNA. All donations were tested for ALT level. RESULTS: The HCVcAg test specificity was 99.94 percent. In total, 1499 donations (1.12%) were initially reactive and 124 (0.09%) were RR. Antibodies to HCV were found in 22 out of 124 donors and HCV RNA was detected in 19 out of 22. In 10 out of the 19 HCV-RNA-positive donors, the HCVcAg neutralization test was positive. Among the 102 HCVcAg RR/anti-HCV-negative donors, there were 6 neutralization-test-positive individuals, and all were HCV RNA positive. Elevated ALT level was observed in one of them. During the follow-up studies of three HCVcAg RR/HCV-RNA-positive donors, seroconvertion was observed 5 to 7 weeks after the initial HCVcAg-positive result. In all, HCVcAg results became negative once antibodies to HCV were detected. CONCLUSION: The HCVcAg test proved to be feasible for routine screening in the Polish Blood Transfusion Service. Six HCVcAg RR/anti-HCV-negative donors were identified. The calculated residual risk in this study of donors in the preseroconversion window was 45 per million. Mandatory testing of every blood and plasma donation for HCVcAg or HCV RNA was recommended as of January 2, 2002.