Evaluation of HIV antibody and antigen/antibody combination ELISAs for use in an alternative confirmatory HIV testing strategy in Dar es Salaam, Tanzania
Journal of Virological Methods
Department of Microbiology and Immunology, Muhimbili University College of Health Sciences, P.O. Box 65001, Dar es Salaam, Tanzania; Swedish Institute for Infectious Disease Control and Microbiology, Tumorbiology Centre, Karolinska Institute, Nobels väg 18, SE-171 82 Solna, Stockholm, Sweden
The aim of this study was to evaluate the performance of two antibody enzyme-linked immunosorbent assays (ELISAs) [Vironostika Uni-Form II plus O and Enzygnost® anti-HIV-1/2 Plus], and two antigen/antibody combination ELISAs [Murex and Vironostika HIV Uni-Form II] for use in an alternative confirmatory HIV diagnostic testing strategy in Dar es Salaam, Tanzania. Altogether, 1380 serum samples were included. All ELISA reactive samples were tested using the Inno-Lia antibody assay and discrepant samples were tested on the Innotest p24 antigen assay. Three hundred and one (21.8%) samples were confirmed HIV-1 antibody positive by Inno-Lia including 27/508 (5.3%) from blood donors, 65/511 (12.7%) from pregnant women and 209/361 (57.9%) from hospital patients. The sensitivity at initial testing was 100% (95% CI; 98.8-100%) for all assays except Vironostika Uni-Form II plus O (99.7%; 95% CI; 98.2-99.9%) which showed one false negative sample at initial testing but 100% sensitivity after repeat testing. The final specificity at repeat testing was 100% (95% CI; 99.7-100%) for Enzygnost® anti-HIV-1/2 Plus, 99.4% (95% CI; 98.8-99.8%) for each of the antigen/antibody combination ELISAs and 97.9% (95% CI; 96.8-98.6%) for Vironostika plus O ELISA. An alternative confirmatory HIV testing strategy based on initial testing on any of the two antigen/antibody assays followed by testing of reactive samples on the Enzygnost® anti-HIV-1/2 Plus assay gave 100% specificity (95% CI; 99.7-100%). © 2006 Elsevier B.V. All rights reserved.
antigen p24; Human immunodeficiency virus antibody; Human immunodeficiency virus antigen; antigen antibody complex; antigen binding; article; blood donor; blood sampling; clinical article; confidence interval; diagnostic test; enzyme linked immunosorbent assay; false negative result; female; hospital patient; human; Human immunodeficiency virus; Human immunodeficiency virus 1; Human immunodeficiency virus 2; Human immunodeficiency virus infection; immunoassay; pregnant woman; priority journal; sensitivity analysis; sensitivity and specificity; Tanzania; AIDS Serodiagnosis; Enzyme-Linked Immunosorbent Assay; HIV Antibodies; HIV Core Protein p24; HIV-1; HIV-2; Humans; Sensitivity and Specificity; Human immunodeficiency virus 1; Murex