Epstein-Barr virus. Coloured transmission electron micrograph (TEM) of Epstein-barr viruses (blue) being shed from a B cell, a type of lymphocyte (white blood cell). The Epstein?arr virus (EBV), also called human herpesvirus 4 (HHV-4), is one of eight viruses in the herpes family, and is one of the most common viruses in humans. It is best known as the cause of infectious mononucleosis (glandular fever). It is also associated with particular forms of cancer, such as Hodgkin's lymphoma, Burkitt's lymphoma, nasopharyngeal carcinoma, and conditions associated with human immunodeficiency virus (HIV). Some 200, 000 cancer cases per year are thought to be attributable to EBV. Magnification: x 20, 000 when printed at 10 centimetres wide.