Diversity and divergence of the viral quasi-species. (A) From each patient pair-wise nucleotide distances before (-) and after (+) initiation of therapy were calculated for each cell subset and serum. Nucleotide distance is presented as percentage and the red bar represents the median value. Pair-wise distances between both time-points were calculated (d) and when this value was higher than the diversity of either time-point it was identified as viral divergence, indicated by an asterisk. Statistical significance was calculated for the difference in diversity before and after therapy start; *** = p < 0.0001. Data from the effector memory subset of M16394 was not available.