RAPID AND SIMPLE HEPATITIS ASSAYS - ENCOURAGING RESULTS FROM A BLOOD-DONOR POPULATION IN ZIMBABWE

A rapid assay to detect antibodies to hepatitis C virus (HCV) in serum and two rapid/simple assays to detect hepatitis B surface antigen (HB sAg) in whole blood/serum were evaluated for their accuracy and suitab ility al the National Blood Transfusion Service, Harare, Zimbabwe. For this purpose, a total of 206 sera (196 routinely collected and 10 fro zen) were tested using the HCV-SPOT(Genelabs Diagnostics), the SimpliR ED HBsAg test (AGEN), and the Dipstick-HBsAg (PATH/Immuno-Chemical Lab oratories). The results were compared with those obtained using a rout ine HBsAg enzyme immunoassay (EIA) (Auszyme, Abbott) and an HCV IgG se cond-generation EIA (Abbott). An HCV IgM test (Abbott) was used for sa mples that produced discordant results, and all HCV-reactive samples w ere confirmed using the INNO-LIA HCV Ab III synthetic peptide assay (I nnogenetics). Overall, the concordance between the HCV-SPOT and the HC V EIA was 97.6% (201/206). For the 193 sera that were true HCV negativ es, the number of false positives was six with the HCV-SPOT test, whil e the HCV EIA produced three (specificity = 97, 0% and 98.5%, resp.). Of these false positives, two were so in both tests. None of the false positives contained IgM antibodies to HCV, and there were no false ne gatives in the two HCV tests. The concordance between the two rapid HB sAg tests and the HBsAg EIA was 99.5% (205/206). All the rapid/simple tests were easy to perform and interpret, required no (or minimal) lab oratory equipment, and could be taught easily to local laboratory pers onnel. The cost of these tests is equivalent to or less than that of r outine EIA methods.