Description
Epstein-Barr Virus (EBV), a DNA virus, is a member of the Human Herpesvirus group and is pathogenic for humans.
EBV transmission takes place primarily via the saliva of infected individuals. Transfer of the virus via blood, blood products and bone marrow transplants have also been reported, but this mode of transmission is comparatively rare.
On primary infection, the cells of the salivary gland are infected first. At this stage of infection respiratory symptoms are very common. Due to the subsequent infection of B cells in the adjacent lymphoid tissue, the virus spreads throughout the body. Infection of B cells results in a polyclonal stimulation of lymphoproliferation which is normally controlled by the immune system. In the later course of infection, high fever, splenomegaly, lymphadenitis, thrombocytopenia and hepatitis may be observed. The disease resulting from primary infection is called infectious mononucleosis (IM) or glandular fever. Since viral transmission principally happens by oral contact, the primary infection has also been called "kissing disease". In rare cases acute mononucleosis may progress to a chronic disease, and reactivation of EBV has been observed in immunosuppressed patients.
EBV is closely associated with nasopharyngeal carcinoma, and Burkitt lymphoma (BL), is at least partly correlated with EBV. This B cell tumor of monoclonal origin is endemically clustered in tropical regions of Africa and Asia. The geographical distribution of BL correlates with that of malaria. Since it is believed that infections with Plasmodium have some influence on the immune system, it is suggested that malaria might be an important cofactor for the development of Burkitt lymphoma in these regions.
Due to the complex structure of the virus, the tight regulation of the viral life cycle, and the appearance of latent or productive infections, the antibody response seen after EBV infection may be quite complex and therefore difficult to interpret