The course of untreated HIV infection and changes after antiretroviral therapy: In untreated HIV infection the blood CD4 T cell count progressively declines over the course of infection (A). After initiation of antiretroviral therapy the HIV RNA copy numbers significantly decrease below detection limit followed by recovery of CD4 T cells, which can vary notably between individuals (B). | Maartens G, Celum C, Lewin SR. HIV infection: epidemiology, pathogenesis, treatment, and prevention. Lancet. 2014;384(9939):258–271. doi: 10.1016/S0140-6736(14)60164-1.