Epstein-Barr Virus, or EBV, is the name given to a member of the herpesvirus family that is associated with a variety of illnesses—from infectious mononucleosis (IM), to nasal-pharyngeal cancer, and Burkitt's lymphoma .
Herpesviruses have long been known. The name actually comes from the Greek adjective herpestes, which means creeping. Many herpesvirus species appear to establish a life-long presence in the human body, remaining dormant for long periods and becoming active for some, often inexplicable, reason. EBV is only one of several members of the Herpesvirus family that have similar traits. Others include varicella zoster virus—the cause of both chickenpox and shingles—, and the herpes simplex virus responsible for both cold sores and genital herpes. EBV is usually transmitted through saliva but not blood, and is not normally an airborne infection.
EBV occurs in nearly all regions of the world, and is considered among the most common infectious viruses known to humankind. In the United States, the Center for Disease Control (CDC) estimates that 95% of adult Americans between the ages of 35 and 40 years have been infected, but it is less prevalent in children and teenagers. This pattern of infecting adults more than children persists throughout other prosperous western countries, but does not hold true in underdeveloped regions such as Africa and Asia. In Africa, most children have been infected by EBV by the age of three years
Individuals with EBV infections typically show some elevation in the white blood cell count and a noticeable increase in lymphocytes—white blood cells associated with the immune response of the body. IM is a time-limited infection that usually lasts from one to two months. Symptoms include fever , malaise, sore throat, swollen glands and (sometimes) swollen spleen and/or liver. EBV infections that lead to Burkitt's lymphoma in Africa typically affect the jaw and mouth area, while the (very rare) incidences of Burkitt's lymphoma found in developed countries are more apt to manifest tumors in the abdominal region. Nasopharyngeal cancer is uncommon in the West but more prevalent in the Far East. It affects more men than women, and usually occurs between the ages of 40 and 50 years.
EBV has been linked to IM in the Western world for decades. It has also become associated consistently with nasopharyngeal cancers in Asia (especially China) and Burkitt's lymphoma in Africa and Papua New Guinea. According to the CDC, EBV is not the sole cause of these two malignancies, but does play an important role in the development of both cancers. The mechanism that allows Epstein-Barr Virus to at least help in producing such diverse illnesses in diverse regions of the world has been the subject of increasing research and scrutiny.
It is known that, once it infects a person, EBV is one of the herpesviruses that remain in the human body for life. Under certain, still not-understood conditions, it alters white blood cells normally associated with the immune system, changing B lymphocytes (those normally associated with making antibodies), and causing them to reproduce rampantly. EBV can bind to these white blood cells to produce a solid mass made up of B lymphocytes— called Burkitt's lymphoma—or to the mucous membranes of the mouth and nose and cause nasopharyngeal cancer. Since Burkitt's lymphoma typically occurs in people living in moist, tropical climates, the same regions where people usually contract malaria, it has been speculated that the immune system is altered by its response to malaria. When EBV infection occurs, the altered immune system's reaction is the production of a tumor.
Though studies about the hereditary tendency of abnormal cell development after EBV infection are incomplete, some studies have shown it to be a hereditary trait based upon the X chromosome.
Because EBV infections are viral in origin, antibiotics are ineffective against them. Much research is geared toward the development of a vaccines effective against both the virus and cancer.
Anticancer drugs, such as cyclophosphamide , or radiation therapy have been shown to be effective against Burkitt's lymphoma in four out of five cases.
Alternative and complementary therapies
The goal of alternative treatment is to lower the white blood cell count to normal levels. Treatment often includes nutritional supplements such as flaxseed oil or shark cartilage, vitamins—including vitamins C and K, and mineral supplements containing magnesium and potassium. Well-conducted randomized clinical trials have not yet been conducted to prove efficacy of these therapies.
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Queensland Institute of Medical Research <http:firstname.lastname@example.org> 12/7/99
Center for Disease Control, National Center for Infectious Diseases Epstein-Barr Virus and Infectious Mononucleosis <http://www.cdc.gov.org> 3/26/01
Joan Schonbeck, R.N.
—Any of a group of white blood cells of crucial importance to the immune system's production of a tailor-made defense against specific invading organisms.
—A group of cancers in which the cells of tissue usually found in the lymph nodes or spleen multiply abnormally.
—A serious disease prevalent in the tropics. It is caused by parasites and produces severe fever and sometimes complications affecting the kidneys, liver, brain, and blood. It is spread by the Anopheles mosquito and can be fatal.
—Affecting the passage connecting the nasal cavity behind the nose to the top of the throat behind the soft palate.
QUESTIONS TO ASK THE DOCTOR
- What tests can be done if Epstein-Barr Virus infection is suspected?
- Have any vaccines against Epstein-Barr Virus been developed?
"Epstein-Barr Virus." Gale Encyclopedia of Cancer. . Encyclopedia.com. (February 25, 2017). http://www.encyclopedia.com/medicine/encyclopedias-almanacs-transcripts-and-maps/epstein-barr-virus
"Epstein-Barr Virus." Gale Encyclopedia of Cancer. . Retrieved February 25, 2017 from Encyclopedia.com: http://www.encyclopedia.com/medicine/encyclopedias-almanacs-transcripts-and-maps/epstein-barr-virus
Epstein-Barr virus (EBV) is part of the family of human herpes viruses . Infectious mononucleosis (IM) is the most common disease manifestation of this virus, which once established in the host, can never be completely eradicated. Very little can be done to treat EBV; most methods can only alleviate resultant symptoms.
In addition to infectious mononucleosis, EBV has also been identified in association with—although not necessarily believed to cause—as many as 50 different illnesses and diseases, including chronic fatigue syndrome, rheumatoid arthritis, arthralgia (joint pain without inflammation ), and myalgia (muscle pain). While studying aplastic anemia (failure of bone marrow to produce sufficient red blood cells), researchers identified EBV in bone marrow cells of some patients, suggesting the virus may be one causative agent in the disease. Also, several types of cancer can be linked to presence of EBV, particularly in those with suppressed immune systems, for example, suffering from AIDS or having recently undergone kidney or liver transplantation. The diseases include hairy cell leukemia, Hodgkin's and non-Hodgkin lymphoma, Burkitt's lymphoma (cancer of the lymphatic system endemic to populations in Africa), and nasopharyngeal carcinoma (cancers of the nose, throat, and thymus gland, particularly prevalent in East Asia). Recently, EBV has been associated with malignant smooth-muscle tissue tumors in immunocompromised children. Such tumors were found in several children with AIDS and some who had received liver transplants. Conversely, it appears that immunosuppressed adults show no elevated rates of these tumors.
Epstein-Barr virus was first discovered in 1964 by three researchers—Epstein, Achong, and Barr—while studying a form of cancer prevalent in Africa called Burkitt's lymphoma. Later, its role in IM was identified. A surge of interest in the virus has now determined that up to 95% of all adults have been infected with EBV at some stage of their lives. In seriously immunocompromised individuals and those with inherited immune system deficiencies, the virus can become chronic, resulting in "chronic Epstein-Barr virus" which can be fatal.
EBV is restricted to a very few cells in the host. Initially, the infection begins with its occupation and replication in the thin layer of tissue lining the mouth, throat, and cervix, which allow viral replication. The virus then invades the B cells , which do not facilitate the virus's replication but do permit its occupation. Infected B cells may lie dormant for long periods or start rapidly producing new cells. Once activated in this way, the B cells often produce antibodies against the virus residing in them. EBV is controlled and contained by killer cells and suppressor cells known as CD4 T lymphocytes in the immune system. Later, certain cytotoxic (destructive) CD8 T lymphocytes with specific action against EBV also come into play. These cells normally defend the host against the spread of EBV for the life of the host.
A healthy body usually provides effective immunity to EBV in the form of several different antibodies, but when this natural defense mechanism is weakened by factors that suppress its normal functioning—factors such as AIDS, organ transplantation, bone marrow failure, chemotherapy and other drugs used to treat malignancies, or even extended periods of lack of sleep and overexertion—EBV escape from their homes in the B cells, disseminate to other bodily tissue, and manifest in disease.
Infection is determined by testing for the antibodies produced by the immune system to fight the virus. The level of a particular antibody—the heterophile antibody—in the blood stream is a good indicator of the intensity and stage of EBV infection. Even though EBV proliferates in the mouth and throat, cultures taken from that area to determine infection are time-consuming, cumbersome, and usually not accurate.
Spread of the virus from one person to another requires close contact. Because of viral proliferation and replication in the lining of the mouth, infectious mononucleosis is often dubbed "the kissing disease." Also, because it inhabits cervical cells, researchers now suspect EBV may be sexually transmitted. Rarely is EBV transmitted via blood transfusion.
EBV is one of the latent viruses, which means it may be present in the body, lying dormant often for many years and manifesting no symptoms of disease. The percentage of shedding (transmission) of the virus from the mouth is highest in people with active IM or who have become immunocompromised for other reasons. A person with active IM can prevent transmission of the disease by avoiding direct contact—such as kissing—with uninfected people. However, shedding has been found to occur in 15% of adults who test positive for antibodies but who show no other signs of infection, thus allowing the virus to be transmitted. Research efforts are directed at finding a suitable vaccine .
The prevalence of antibodies against EBV in the general population is high in developing countries and lower socioeconomic groups where individuals become exposed to the virus at a very young age. In developed countries, such as the United States, only 50% of the population shows traces of antibody by the age of five years, with an additional 12% in college-aged adolescents, half of whom will actually develop IM. This situation indicates that children and young persons between the ages of 10 and 21 years are highly susceptible to IM in developed countries, making it a significant health problem among students.
See also Latent viruses and diseases; Mononucleosis, infectious; Viruses and responses to viral infection
"Epstein-Barr Virus." World of Microbiology and Immunology. . Encyclopedia.com. (February 25, 2017). http://www.encyclopedia.com/science/encyclopedias-almanacs-transcripts-and-maps/epstein-barr-virus
"Epstein-Barr Virus." World of Microbiology and Immunology. . Retrieved February 25, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/encyclopedias-almanacs-transcripts-and-maps/epstein-barr-virus
Epstein-Barr virus (EBV), herpesvirus that is the major cause of infectious mononucleosis and is associated with a number of cancers, particularly lymphomas in immunosuppressed persons, including persons with AIDS. Epstein-Barr is a ubiquitous virus, so common that it has been difficult to determine whether it is the cause of certain diseases or whether it is simply there as an artifact. In Third World nations, most children are infected with EBV; in most industrialized nations, about 50% of the people are infected. Research has found that all of the lymphomas associated with AIDS and most lymphomas in other immunocompromised persons are connected with latent EBV infection. EBV has been found in biopsy tissue of patients with Hodgkin's disease, breast cancer, and some smooth muscle tumors. EBV also was formerly suspected as the cause of chronic fatigue syndrome (originally named chronic EBV syndrome).
"Epstein-Barr virus." The Columbia Encyclopedia, 6th ed.. . Encyclopedia.com. (February 25, 2017). http://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/epstein-barr-virus
"Epstein-Barr virus." The Columbia Encyclopedia, 6th ed.. . Retrieved February 25, 2017 from Encyclopedia.com: http://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/epstein-barr-virus
"Epstein-Barr virus." A Dictionary of Nursing. . Encyclopedia.com. (February 25, 2017). http://www.encyclopedia.com/caregiving/dictionaries-thesauruses-pictures-and-press-releases/epstein-barr-virus
"Epstein-Barr virus." A Dictionary of Nursing. . Retrieved February 25, 2017 from Encyclopedia.com: http://www.encyclopedia.com/caregiving/dictionaries-thesauruses-pictures-and-press-releases/epstein-barr-virus