Epstein-Barr virus (EBV), also known as human herpesvirus 4, is a member of the herpes virus family. It was the first oncogenic virus to be discovered. Infection by this virus can show signs of a slight viral infection or it can be present as Infectious Mononucleosis. The most common target cells for the Epstein-Barr virus are the B lymphocytes and the nasopharyngeal epithelial cells. The Epstein-Barr virus massively infects the human population and sero-epidemiological studies show that 90% of adults have been infected by this virus. There are numerous human tumors associated with EBV. These range from non-differentiated nasopharyngeal carcinoma to African Burkitt’s lymphoma, Hodgkin’s disease mixed cellularity, some B, T and NK lymphomas, as well as in lymphoproliferative processes associated with immunodeficiency. The EBV Probe is intended to be used for the qualitative detection of human Epstein-Barr virus (EBV) EBER RNA in formalin-fixed, paraffin-embedded specimens, by chromogenic in situ hybridization (CISH). A positive reactivity for Epstein-Barr-virus (EBV) EBER RNA in the target cells is indicated by a distinctly stained nucleus. Colored precipitates, which can be clearly distinguished from the background, will be dark brown when using DAB for detection.