Fig. 2.

Virus acquisition, progression of the infection and CD4 + T cell decline in vaccinated animals and controls. a–b, plasma viral load in blood samples from individual macaques in vaccinated (a) and PBS injected controls (b). Arrows indicate the timing of the rectal challenges. c, detection of infection in vaccinated and controls animals. Infections were assumed to occur the week before virus was first detectable in plasma. d, progression of infection following acquisition. Shown are plasma viral load in all animals synchronized to the day of infection. Aviremic vaccinees are shown at the detection limit of the assay. e–f, CD4 + T cells in blood synchronized to the day of the successful infection in vaccinated animals (e) and controls (f).