CD4+ T-cell counting is usually performed on whole blood obtained from standard venipuncture. Venipuncture requires expertise, results in discomfort and generates biological waste. Capillary blood could be used to measure the levels of CD4+ T-cell in children, elderly and very ill patients. We studied the agreement between CD4+ T-cell counts and percent generated using venous blood with those obtained with capillary blood in HIV-infected adults and children in a resource-limited tropical setting...