Epstein-Barr virus (EBV), or human gammaherpesvirus 4, is in the herpes family of viruses and most people will become infected with EBV sometimes during their lives. In the United States, as many as 95 percent of adults between 35 and 40 years of age have been infected. The primary infection is acute infectious mononucleosis. Infectious mononucleosis, "mono," "kissing disease," and “glandular fever” are all terms popularly used for the very common illness caused by EBV. The Epstein-Barr virus is named after the scientists who first identified it in the mid-1960s.
"Mononucleosis" refers to an increase in one type of white blood cells (lymphocytes) in the bloodstream relative to the other blood components as a result of the Epstein-Barr virus infection. The virus enters the lymph nodes and attacks the the white blood cells (lymphocytes). As the white blood cells come into contact with the virus, they change shape and multiply. At first, there are no symptoms because it takes several weeks before enough of the altered cells can accumulate to generate infection.
The Epstein-Barr virus is also a human tumor virus, the first virus identified with human malignancy. The Epstein-Barr virus is associated with lymphoproliferative disorders, especially in immunocompromised people, and is linked to various tumors, including Burkitt lymphoma, Hodgkin lymphoma and nasopharyngeal carcinoma.
If the virus lasts more than six months, it is frequently called chronic EBV infection. Although it has not been definitively proven, some doctors believe EBV is the cause of a chronic condition called Chronic Fatigue Syndrome (CFS).
Infectious mononucleosis is a contagious viral illness that initially attacks the lymph nodes in the neck and throat. The majority of infections may produce no symptoms or develop slowly with such mild symptoms that it may initially resemble a cold or the flu. Classic symptoms include sore throat, fever, fatigue, malaise, and swollen/enlarged lymph nodes. These symptoms can be mild or so severe that throat pain impedes swallowing and the fever reaches 105 degrees F. Some people may get a rash, or experience eye pain, discomfort with bright light (photophobia), a swollen spleen or liver infection.
Mononucleosis is most often diagnosed in adolescents and young adults, with a peak incidence at 15-17 years of age. Infection with EBV in younger children is usually asymptomatic or mild and may mimic the symptoms of other common childhood illnesses, which may explain why it is less commonly diagnosed in this age group.
The incubation period for the disease is usually seven to 14 days in children and adolescents. The incubation period in adults is longer; at times it may be 30 to 50 days.
Although the symptoms of mono only lasts for one or two months, the EBV remains dormant in cells in the throat and blood for the rest of the person's life. The virus can reactivate and can be found in the saliva of infected persons. This reactivation usually occurs without symptoms. EBV also establishes a lifelong dormant infection in some cells of the body's immune system.
After a young person has the symptoms of fever, sore throat, swollen lymph glands, a physical examination may reveal an enlarged or tender liver or spleen. With a positive reaction to a "monospot blood test " an increased percentage of certain white blood cells can be detected. A monospot test works by detecting certain proteins called heterophile antibodies. Since it takes time for antibodies to develop after infected, it's possible for the first monospot test to be negative, even if EBV is present. The test may need to be repeated in a week or two.
Different laboratory tests can measure specific EBV antibodies. Testing can be done on a single sample of blood, or can compare different samples of blood over a period of time.
Epstein-Barr virus is most commonly transmitted through infectious saliva. It can occur as an epidemic or as a single case. Mono spreads by contact with moisture from the mouth and throat of a person who is infected. Thus, the nickname, “kissing disease”. Kissing, sharing eating utensils, drinking glasses, and toothbrushes, or touching anything that has been near the mouth of an infected person, may result in transmission of the disease.
Mono is usually self-limited and there is no specific treatment. Bed rest and plenty of fluids are recommended. Resume normal activities as strength rebounds and temperature returns to normal.
However, mono can be accompanied by a streptococcal infection of the throat, which can be treated with an antibiotic.
In severe cases, corticosteroid drugs can be prescribed to reduce swelling. It may be recommended to avoid strenuous activities such as lifting and pushing, as well as any contact sports, if the spleen is swollen and can rupture. If there is a serious complication, such as rupture of the spleen, hospitalization is necessary.