Wantai BioPharm confirmation tests are intended for use as supplemental tests for human serum or plasma specimens found to be repeatedly active in HCV and HIV antibody screening procedures. Tests used for the diagnosis of HIV and HCV infection require a high degree of both sensitivity and specificity, which is achieved using an algorithm combining two tests. Once antibodies have been detected by an initial ELISA test, a second supplemental test using the immunoblot procedure is applied and confirms or excludes the results of the initial ELISA test.