CD27 and infection: In both children and adults, a higher frequency of CD8+/CD38+/HLA-DR+ T cells within the TCM/TEM/T naïve (TN; CD45RO-, CD27+, CCR7+, CD95-) subsets were observed at T1 (4.1%/4.9%/0.33% (children) and 5.5%/3.1%/1.0% (adults)) that declined in time after infection (to 2.7%/2.1%/0.17% (children) and 2.7%/1.7%/0.30% (adults) at T2 and to 2.2%/0.81%/0.23% (adults) at T3 (Supplementary Figures 2A, B, lower panels).