Definition of Acute cytomegalovirus (CMV) infection:

Acute cytomegalovirus (CMV) infection is a condition caused by a member of the herpesvirus family. In most people with a normal immune system, CMV infection does not cause any symptoms. But, some people with this infection develop a "mononucleosis syndrome."

See also: Mononucleosis

Causes, incidence, and risk factors:

Mononucleosis can be caused by several different viruses and a few types of bacteria. Unlike the more common form of mononucleosis, caused by the Epstein-Barr virus (EBV), acute CMV infection is caused by cytomegalovirus (CMV).

The symptoms of mononucleosis syndrome with CMV include fever and fatigue. Swollen lymph glands in the neck, sore throat, and swollen spleen are less common with CMV. Up to a third of patients may have a rash.

The infection is spread by saliva, urine, respiratory droplets, sexual contact, and blood transfusions. Some young children release the virus in their urine for a long period of time, even when they do not have symptoms. CMV infection may occur at any age. It most commonly develops between the ages of 10 and 35.

Most people are exposed to CMV early in life and do not realize it because they have no symptoms.