In the United States and in other developed countries, many persons are not infected with EBV in their childhood years. In these people, infection with Epstein-Barr virus during adolescence or young adulthood commonly causes infectious mononucleosis.

Symptoms of infectious mononucleosis are fever, sore throat, and swollen lymph glands. Sometimes there is also a swollen spleen or liver infection. Heart problems or involvement of the central nervous system occur only rarely, and infectious mononucleosis is almost never fatal. There are no known associations between active Epstein-Barr virus infection and problems during pregnancy, such as miscarriages or birth defects. Although the symptoms of infectious mononucleosis usually resolve in one or two months, the Epstein-Barr virus remains dormant in cells in the throat and blood for the rest of the person's life. Periodically, the virus can reactivate and can be found in the saliva of infected persons. This reactivation usually occurs without symptoms of illness.

EBV also establishes a lifelong dormant infection in some cells of the body's immune system. A late event in a very few viral carriers is the emergence of Burkitt's lymphoma and nasopharyngeal carcinoma, two rare cancers that are not normally found in the United States. EBV appears to play an important role in these malignancies, but is probably not the sole cause of disease.

Most individuals exposed to people with infectious mononucleosis have previously been infected with EBV and are not at risk of developing infectious mononucleosis. In addition, transmission of EBV requires contact with the saliva (found in the mouth) of an infected person. Transmission of this virus through the air or blood does not normally occur. The incubation period, or the time from infection to appearance of symptoms, ranges from 4 to 6 weeks. Thus persons with infectious mononucleosis may be able to spread the infection to others for a period of time. However, no special precautions or isolation procedures are recommended since the virus is also found frequently in the saliva of healthy people. In fact, many healthy people can carry and spread the virus intermittently for life. These people are usually the primary reservoir for person-to-person transmission. For this reason, transmission of the virus is almost impossible to prevent.

The diagnosis of infectious mononucleosis is suggested on the basis of the clinical symptoms of fever, sore throat, swollen lymph glands, and the age of the patient. Usually, laboratory tests are needed for confirmation.

Blood findings with infectious mononucleosis include an elevated white blood cell count, an increased percentage of certain white blood cells, and a positive reaction to a "mono spot test."

There is no specific treatment for infectious mononucleosis, other than treating the symptoms. No antiviral drugs or vaccines are available. Some physicians have prescribed a five day course of steroids to control the swelling of the tonsils. The use of steroids has also been reported to decrease the overall length and severity of illness, but these reports have not been published.

*** Please note: Symptoms related to infectious mononucleosis due to EBV, as confirmed in the laboratory seldom last for more than 3 or 4 months. When such an illness lasts more than 6 months, it is frequently called chronic EBV infection. However, valid evidence for continued active EBV infection is found very seldom in these patients, and their illness is usually more appropriately described as chronic fatigue syndrome, or CFS.

NEW EPSTEIN-BARR TEST KIT AVAILABLE SOON? Monday, August 24, 1998 Gull Laboratories and Quest Diagnostics jointly announced today that Quest's new test kit for the Epstein-Barr virus will be supplied by Gull on a three-year contract to begin on September 1, 1998. EBV has been associated with some cases of chronic fatigue syndrome. The new test not only detects the presence of antibodies to the virus, but is also capable of detecting whether the infection is in the acute, convalescent or reactivated stage. The press release did not give an exact date when the kits would be available to the public, but Quest says it expects to perform over half a million tests the first year, and 20 percent more each year after that. Source of information: PRNewswire release by Gull Laboratories, Inc.