Cytomegalovirus (CMV) is a common virus that can infect almost anyone. CMV is a type of herpesvirus (herpesvirus type 5). Blood tests show that 60 to 90% of adults have had a CMV infection at some time.CMV may cause symptoms soon after infection. Also, it remains dormant (inactive) in various tissues for life. Various stimuli can reactivate the dormant CMV, resulting in disease. The lungs, gastrointestinal tract, brain, spinal cord, or eyes may be infected.There are two different types of Cytomegalovirus (CMV) Infection: primary CMV and recurrent CMV infection. Primary CMV infection can cause more serious problems in pregnancy than recurrent CMV infection can. CMV is a member of the herpes virus group that is characterized by the ability to remain dormant within the body over a long period.  Infectious CMV may be shed in bodily fluids (urine, saliva, blood, tears, semen, and breast milk) intermittently without any detectable signs or symptoms.