(also called glandular fever, or kissing disease, or mono), infectious virus disease marked by fatigue, sore throat, fever, and swollen lymph glands, usually in the neck. The symptoms may include rash, enlarged spleen, and involvement of the liver and nervous system. It is caused by either the Epstein-Barr virus or cytomegalovirus, both members of the herpesvirus family. It is diagnosed by a blood test showing changes in the white blood cells (also called lymphocytes or mononuclear cells). Most common in the 10-to-35 age group, the virus is spread by contact with an infected person's saliva. Treatment includes drinking plenty of fluids, bed rest, and pain relievers. The infection usually lasts 4 to 6 weeks, and sometimes longer. It takes the body's immune system about a month to destroy the virus and patients can feel depressed and exhausted for several months after recovery. Second attacks are rare,