In the absence of vitamin supplementation, such an individual would display trends similar to those observed in Figure 4: an initially healthy concentration of CD4+ T cells is followed, upon infection, by a sharp decline in the number of uninfected CD4+ T cells which eventually equilibrates at a significantly lower concentration of 317 cells/μL. In addition, the ROS concentration increases to an equilibrium value well beyond normal levels and the antioxidant concentration decreases. This evidence concerns the gene CD4 and infection.