No randomized clinical trial to date has demonstrated a survival benefit of using regular HIV-1 ribonucleic acid (RNA) viral load (VL) testing to monitor patients' responses to antiretroviral therapy (ART) for HIV infection. The measurement of VL is recommended to monitor the response to ART in developed countries. In resource-constrained settings, the World Health Organization (WHO) does not recommend routine VL testing, in part due to the cost and complex infrastructure needed for reliable results. In these settings, WHO has proposed the use of clinical and CD4+ lymphocyte-based criteria to guide treatment decisions. However, multiple studies have demonstrated the poor performance of these criteria in sub-Saharan Africa and the frequent discordance between immunologic and virologic responses to ART.