Quantitative HIV RNA viral load (QVL) assays (Roche Diagnostics) were sensitive and specific when used to diagnose HIV infection in (i) HIV-exposed infants (sensitivity of 100% [63.1 to 100%] and specificity of 100% [97.9 to 100%]) and (ii) suspected acute HIV infection patients with a negative/indeterminate Western blot (sensitivity of 97.6% [91.6 to 99.7%] and specificity of 100% [96.1 to 100%]). No false-positive QVL results were identified.