Figure 5

Viral rebound after stopping deferred HAART. The drug control effect of HAART on plasma viremia is shown for treated subjects and compared with the viral production in absence of therapy. In the upper panel, from left to right, the viral load, CD4⁺ and CD8⁺ T cell count are plotted as function of years from primary HIV-1 infection. In the lower panel, the histogram of the viral rebound after the first interruption of HAART is shown for three different stages (from top to bottom: 1 month, 6 months and 1 year after therapy termination, respectively) and for in silico patients receiving either immediate (green histogram) or deferred therapy (red histogram). The shadowed area (low viremia <50 RNA copies/ml) corresponds to the successful cases of immune control in drug-free period. We find that in delayed treatment 45% of in silico patients manage to spontaneously control viremia after the first month of therapy interruption and the virus has yet completely rebound one year after discontinuation, approaching the value at which it would level off in the absence of treatment (blue open rectangle).