Naïve and effector memory CD4⁺T-cell reconstitution in context HHV6 viremia. LOESS curves of naïve (A) and effector memory (B) CD4⁺ T-cell counts in blood over time after HCT are depicted in patients with (n = 51; red lines) and without HHV6 viremia (n = 91; blue lines). Patients with steroid-treated severe aGVHD were excluded from these graphs. Gray areas depict 95% CIs of LOESS fit.