Comparison in sensitivity of 10 HIV antibody detection tests by serial dilutions of Western blot-confirmed samples

Nine ELISA tests and one particle agglutination test for the detection of HIV antibodies were analysed using serial dilutions of Western blot-confirmed positive serum samples. These samples were diluted in HIV antibody negative human serum in a range of 1:10 to 1:10,000 or 1:100,000. Remarkable differences in sensitivity were observed. Some tests were 10- to 100-fold more sensitive than others, and even differences of 1000-fold were detected.