After acute infection, CMV titers (red line) fall below the limit of detection. However, stochastic reactivation events stimulate proliferative memory-phenotype T cells (blue line) to divide and differentiate, producing effector T-cell progeny (green line) that are poorly proliferative and have a relatively short half-life.
CMV: Cytomegalovirus; TEFF: Effector T cell; TM: Memory T cell.