CMV is a (hv) herpes virus
(there's 16 of wh/14 infect humans i.E: hsv
, vzv, mono
), hhv6, hhv8). Once infect'd virus stay latent w/in. CMV is an immune modulator turning off response to itself and less so to other herpes viruses. Reactiv'n of one means immune system not holding that virus ; others in check.