Mini-pool screening by nucleic acid testing for hepatitis B virus, hepatitis C virus, and HIV: preliminary results.

BACKGROUND

The purpose of this study was to evaluate the feasibility of nucleic acid testing (NAT) of mini-pools as a blood donation screening test.

STUDY DESIGN AND METHODS

The stepwise implementation of NAT of mini-pools began in January 1997. Since March 1997, all blood donations collected by the German Red Cross Blood Transfusion Service of Baden-Württemberg were tested for hepatitis B virus (HBV), hepatitis C virus (HCV), and HIV nucleic acids. An extra barcoded serum sample is collected from each blood donor for NAT-based screening, which is performed only on hepatitis B surface antigen-, anti-HCV-, anti-HIV-, and anti-Treponema pallidum-seronegative donations. Samples are pooled to a maximum of 96. Positive results are resolved through intersecting subpools (a chessboard design). NAT-based screening does not include a virus concentration step before nucleic acid extraction.

RESULTS

By the end of October 1997, 331, 783 donations in 3,779 pools had been screened. As yet, no viremic but seronegative blood donor has been found for the three markers.

CONCLUSION

It is feasible to incorporate NAT-based screening of mini-pools into the routine virus diagnostics of a large blood transfusion service. It remains to be determined whether screening blood donations by NAT will indeed increase the safety of blood supply.