Multisite Laboratory Evaluation of a Dual Human Immunodeficiency Virus (HIV)/Syphilis Point-of-Care Rapid Test for Simultaneous Detection of HIV and Syphilis Infection

Background. Recently, test developers have created rapid point-of-care tests that can simultaneously detect multiple infections within the same specimen using a single device. The SD BIOLINE Duo HIV/Syphilis rapid point-of-care test uses a solid-phase immunochromatographic assay to detect immunoglobulin (Ig) G, IgM, and IgA antibodies to human immunodeficiency virus (HIV)-specific antigens (HIV-1 gp41, sub O, HIV-2 gp36) and recombinant Treponema pallidum antigen (17 kDa) in human serum. This study was a multisite laboratory-based evaluation of the performance of SD BIOLINE HIV/Syphilis Duo test using previously characterized sera in 6 countries. Methods. Laboratories in Ghana, Mexico, Laos, Togo, Kenya, and Myanmar participated in the evaluation during 2012-2013. Each site characterized sera using T pallidum particle agglutination assay or T pallidum hemagglutination assay and HIV enzyme immunoassay, Western blot, and/or HIV antibody rapid tests. Those gold standard test results were compared with SD BIOLINE Duo test results. We calculated the sensitivity and specificity of test performance and used the exact binomial method to calculate 95% confidence intervals (CIs). Results. The sensitivity and specificity for the HIV antibody test component (n = 2336) were estimated at 99.91% (95% CI, 99.51% and 100%) and 99.67% (95% CI, 99.16% and 99.91%), respectively. For the T pallidum test component (n = 2059), the sensitivity and specificity were estimated at 99.67% (95% CI, 98.82% and 99.96%) and 99.72% (95% CI, 99.29% and 99.92%), respectively. Conclusions. The sensitivity and specificity of the SD BIOLINE HIV/Syphilis Duo test were consistently high across sera specimens from 6 countries around the world. Dual rapid tests should be considered for improved HIV and syphilis screening coverage.