Epstine-Barr Virus (EBV)

The Epstein-Barr virus frequently referred to as EBV, is one
of the most common human viruses, and it occurs world-wide. The
virus is in the herpes family of viruses, and most people will become
with EBV sometime during their lives. In the United States, as many as
95% of adults between 35 and 40 years of age have been infected.
become susceptible to EBV as soon as the maternal protection present at
birth disappears. Many children are infected with EBV and these
infections usually cause no symptoms or are indistinguishable from the
other mild,
brief illnesses of childhood.

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.

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.