Multinational assessment of blood-borne virus testing and transfusion safety on the African continent.

BACKGROUND

Failures of blood screening due to low test quality or poor laboratory technique increase the risk of transfusion-transmitted infections. For this reason, the World Health Organization has recommended a quality control (QC) system for African blood centers.

STUDY DESIGN AND METHODS

We conducted a cross-sectional research assessment of test performance at 51 blood centers in 17 African countries. A blinded, standardized panel containing 25 samples positive for human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) and negative controls was tested by the centers using their operational infectious disease testing consisting of rapid tests, enzyme immunoassays (EIAs), or antigen-antibody EIAs. Nucleic acid testing was not performed.

RESULTS

The overall performances of the 42 assays were the lowest for hepatitis B surface antigen (75.6% sensitivity, 94.5% specificity), then for HCV (80.0% sensitivity, 98.1% specificity) and for HIV (81.4% sensitivity, 99.6% specificity). Poor sensitivity was driven by the use of rapid tests, which had sensitivities of 47.4% for HBV, 63.7% for HCV, and 72.4% for HIV. From a blood screening point of view, 321 (5.6%) infected units would have been transfused due to false-negative results. Assuming that those that were missed by rapid tests (84%) would have been detected by EIAs, 270 viral contaminations (92 HIV, 65 HCV, and 113 HBV) would have been avoided.

CONCLUSION

These results support the discontinuation of rapid tests and implementation of antigen-antibody EIAs whenever possible in Africa. This successful QC program highlights the need for promoting such periodic external quality assessment studies.