Cytomegalovirus (CMV) is a common virus that can infect almost anyone. Most people don't know they have CMV because it rarely causes symptoms. However, if you're pregnant or have a weakened immune system, CMV is cause for concern. Once infected with CMV, your body retains the virus for life. However, CMV usually remains dormant if you're healthy. CMV spreads from person to person through body fluids, such as blood, saliva, urine, semen and breast milk. CMV spread through breast milk usually doesn't make the baby sick. However, if you are pregnant and develop an active infection, you can pass the virus to your baby.

There's no cure for CMV, but drugs can help treat newborns and people with weak immune systems.

Newborns infected with CMV in the womb (congenital CMV), babies who become infected during birth or shortly after birth (perinatal CMV) — such as through breast- feeding — and people with weakened immune systems are more at risk of developing signs and symptoms than are healthy adults.

CMV mononucleosis. This syndrome resembles infectious mononucleosis, but the Epstein-Barr virus (EBV) causes classic mononucleosis. The symptoms are sometimes very mild. In some cases, it can cause tiredness and weakness for few weeks. In most cases we don’t need to treat the CMV. It is important to take adequate rest and proper diet. Avoiding strenuous activity and participating in contact sports may be necessary until the weakness goes away.