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Background:  Access to HIV testing is a critical component of HIV prevention and care services. Because of their ease of use, rapid HIV tests are being widely used to provide HIV testing services in resource-poor countries, and in-country evaluations and quality assurance of point-of-service testing are important steps in establishing high-quality testing. To date there is limited information concerning the outcomes of these evaluations and of the performance of rapid tests in clinical settings.

Methods:  A questionnaire regarding evaluation and implementation of rapid HIV tests was administered to personnel in ministries of health and reference laboratories in 11 African countries where CDC has assisted in improving laboratory capacity. Existing HIV testing algorithms in each country served as the gold standard for measuring rapid test performance.

Results:  Results are available from rapid HIV test evaluations conducted between 2001 and 2003 in reference laboratories in 10 of the 11 countries. In all, 18 different rapid tests were evaluated. Median sensitivity for each test ranged from 92.5% to 100% and exceeded 99% for 12 tests. Median specificity ranged from 95.3% to 100% and exceeded 99% for 14 tests. Subsequent evaluations at point-of-service sites in 5 countries yielded results comparable with those of reference laboratory evaluations. To date, a standard rapid testing algorithm has been implemented in 9 countries in more than 600 sites including voluntary counseling and testing centers, antenatal clinics, blood donation centers, hospitals, and clinics. A median of 96,000 (range 15,000 to 315,000) people were tested in each country in 2003:  6 countries used a serial (consecutive) testing algorithm and 3 countries used a parallel algorithm. Quality assurance in 4 countries involved retesting a sample of positive and negative specimens. Median concordance between on-site rapid testing and reference laboratory retesting was 98.7% (range 95.7% to 99.5%).

Conclusions:  In-country evaluations of rapid HIV tests throughout sub-Saharan Africa yield results comparable to those obtained in more controlled evaluations. Furthermore, quality assurance data show the accuracy of point-of-service testing conducted by persons with varying levels of technical skill. As rapid testing is widely implemented in many countries, ongoing quality assurance is essential for maintaining high-quality HIV testing services.

Keywords: Rapid HIV testing; Field evaluation of rapid HIV tests; Implementation of HIV testing