CD4 and malaria: Using CD45RO and CD45RA to distinguish memory and naive T cells, respectively, we found a high ratio of memory to naive CD4+ lymphocytes in cerebral and uncomplicated malaria (median ratios, 0.85 and 0.62, respectively) compared with controls and children with severe malarial anemia (both 0.40) (cerebral malaria or uncomplicated malaria compared to severe malarial anemia or controls, P < 0.001 for all pairwise comparisons, except uncomplicated malaria and severe malarial anemia, where P was 0.002) (Table 4; Fig. 4).