Epstein-Barr Virus
There are several forms of Epstein–Barr virus infection. Infectious mononucleosis, nasopharyngeal carcinoma, and Burkitt's lymphoma can all be caused by the Epstein-Barr virus.
Pathology
Infectious mononucleosis
Epstein-Barr can cause infectious mononucleosis, also known as 'glandular fever', 'Mono' and 'Pfeiffer's disease'. Infectious mononucleosis is caused when a person is first exposed to the virus during or after adolescence. Though once deemed "The Kissing Disease," recent research has shown that transmission of Mono not only occurs from exchanging saliva, but also from contact with the airborne virus.[citation needed] It is predominantly found in the developing world, and most children in the developing world are found to have already been infected by around 18 months of age. EBV antibody tests turn up almost universally positive. In the United States roughly half of five-year-olds have been infected,[1].
EBV-associated malignancies
The strongest evidence linking EBV and cancer formation is found in Burkitt's lymphoma and nasopharyngeal carcinoma. Additionally, it has been postulated to be a trigger for a subset of chronic fatigue syndrome patients[2] as well as multiple sclerosis and other autoimmune diseases.[3]
Burkitt's lymphoma is a type of Non-Hodgkin's lymphoma and is most common in equatorial Africa and is co-existent with the presence of malaria.[4] Malaria infection causes reduced immune surveillance of B cells immortalized by EBV, resulting in an excessive number of B cells and an increased likelihood of an unchecked mutation. Repeated mutations can lead to loss of cell-cycle control, causing excessive proliferation observed as Burkitt's lymphoma. Burkitt's lymphoma commonly affects the jaw bone, forming a huge tumor mass. It responds quickly to chemotherapy treatment, namely cyclophosphamide, but recurrence is common.
Other B cell lymphomas arise in immunocompromised patients such as those with AIDS or who have undergone organ transplantation with associated immunosuppression (Post-Transplant Lymphoproliferative Disorder (PTLPD)). Smooth muscle tumors are also associated with the virus in malignant patients.[5]
Nasopharyngeal carcinoma is a cancer found in the upper respiratory tract, most commonly in the nasopharynx, and is linked to the EBV virus. It is found predominantly in Southern China and Africa, due to both genetic and environmental factors. It is much more common in people of Chinese ancestry (genetic), but is also linked to the Chinese diet of a high amount of smoked fish, which contain nitrosamines, well known carcinogens (environmental).[6]