The EBV-VCA IgM ELISA tests system is an enzyme linked immunosorbent assay (ELISA) for the detection of IgG class antibodies to EBV in human serum or plasma. Epstein-Barr virus (EBV) is a herpes virus known to cause infectious mononucleosis (IM). EBV infection may demonstrate a wide spectrum of clinical symptoms. The majorities of primary EBV infections are transmitted via saliva, occur during childhood, and are sub-clinical. In the U.S., 50% of the population demonstrate EBV antibodies before the age of 5 years; 80% by adulthood.