CD34 and disease arising from reactivation of latent virus: Taken as a whole, accumulating data on the immune-modulating proteins of HCMV and RhCMV highlight their central role during all phases of the infectious cycle within an infected host, beginning with the immediate virus-mediated modulation of host immune responses at the mucosal surface of a naïve host, to maintenance of an immune suppressive environment in latently infection CD34+ cells, to suppression of effector/memory responses during reinfection of an immune host.