Transfusion safety on the African continent: an international quality control of virus testing in blood banks.
BACKGROUND
Following World Health Organization recommendations that a quality control (QC) system be implemented in African blood centers, a pilot study of the performance of human immunodeficiency virus antibody (anti-HIV), hepatitis B surface antigen (HBsAg), and hepatitis C virus antibody (anti-HCV) testing by several Sub-Saharan African blood centers was initiated.


METHODS
A reference laboratory sent a panel of 25 samples to six African blood center laboratories. The panel included eight negative samples; four anti-HIV-1–, one anti-HIV-2–, four anti-HCV–, and five HBsAg-positive samples; and three samples consisting of mixtures of two sera to mimic coinfections. Sensitivity, specificity, and overall quality (correct positive or negative status) scores were calculated.


RESULTS
From the 21 sets of results obtained (seven for each virus), eight were from rapid tests (two for HIV, three for HBV, and three for HCV) and 13 were from enzyme immunoassays (EIAs; all HIV EIAs were antigen/antibody combination assays). Overall assay sensitivity was 98% for HIV, 75% for HBV, and 88% for HCV; agreement between blood centers using the same assay was good. Sensitivity of rapid tests was notably poorer than EIAs, with overall sensitivity quality scores of 64.5% for rapid tests (20% for HBsAg rapid tests) compared to 100% for EIAs. The overall specificity quality scores were 98.3 and 94.5% for EIAs and rapid tests, respectively.


CONCLUSIONS
This pilot QC study organized for blood centers of Sub-Saharan Africa showed the feasibility of the approach despite some logistic constraints. Although interlaboratory variability was small, the poor performance of rapid tests, especially for HBsAg, raises policy questions about their use as the only screening assay.
Laperche
Syria
S
National Reference Center for Hepatitis B and C and HIV in Transfusion, National Blood Transfusion Institute, 6 Rue Alexandre Cabanel, F-75015 Paris, France. slaperche@ints.fr
Boukatou
Geneviève
G
Kouegnigan
Léonard
L
Nébié
Yacouba
Y
Boulahi
Mohamed Ould
MO
Tagny
Claude Tayou
CT
Yahaya
Rakia
R
Tapko
Jean-Baptiste
JB
Murphy
Edward
E
Lefrère
Jean Jacques
JJ
D000349:Africa; D001771:Blood Banks; D001803:Blood Transfusion; D015483:HIV Antibodies / Q000097:blood*; D006514:Hepatitis B Surface Antigens / Q000097:blood*; D018937:Hepatitis C Antibodies / Q000097:blood*; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods; D010865:Pilot Projects; D011786:Quality Control; D012449:Safety; D012680:Sensitivity and Specificity; D013647:Task Performance and Analysis
D015483:HIV Antibodies; D006514:Hepatitis B Surface Antigens; D018937:Hepatitis C Antibodies