Evaluation of rapid HIV testing strategies in under equipped laboratories in the Central African Republic

Voluntary testing is described as being cornerstone to impact the spread of human immunodeficiency virus (HIV) infection if the person who tests positive is counseled. Therefore, simple, accurate and affordable diagnostic tests are required. The immunoblot test used in developed countries is too expensive for large-scale use in developing countries. Therefore, alternative strategies must be developed. A strategy based on two consecutive rapid tests was tested. This strategy used the Determine HIV-1/2 (Abbott Laboratories, Tokyo, Japan) rapid immunochromatographic test as a screening test and the Uni-Gold HIV test (Trinity Biotech, Dublin, Ireland), SDHO HIV 1/2 test (SDHO laboratories, Saint-Sauveur des Monts, Canada), HIV 1/2 Quick test (Cypress Diagnostics, Langdorp, Belgium) or Retrocheck HIV test (Qualpro Diagnostics, Goa, India) as a confirmatory test. Reference serum samples (HIV-positive and HIV-negative) were first used to evaluate the four confirmatory tests. Secondly, 159 serum samples were used to compare the "consecutive" testing strategy used in our laboratory with the two-test strategy. Thirdly, we tested the feasibility of using this two-test strategy in a under equipped laboratory. The sensitivity and negative predictive value of both test strategies were 100%. The specificity and positive predictive value of the four confirmatory tests were similar (>98%). The strategy used in our laboratory and the two-test strategy always gave identical results, regardless of where this strategy was performed (Institut Pasteur de Bangui or M'baïki hospital). This new strategy appears to be reliable, simple, feasible and rapid in under equipped laboratories. It allows counseling and results to be given on the same day, which should improve post-test counseling.