CD8A and infection: Of all R5-tropic infections, the baseline CD4+ T cell count (p < 0.0001, p < 0.0001) and baseline CD4+ T/CD8+ T ratio (p < 0.0001, p = 0.0075) were lower in CRF01_AE compared to CRF07_BC and CRF08_BC (Figures 4A,B).