The IgM antibody test for Epstein-Barr virus (EBV) VCA detects acute EBV infection. EBV, a human herpesvirus 4, is exclusive to humans and belongs to the gamma herpesvirus family. IgM antibodies usually appear at the same time as IgG but disappear in 4-6 weeks or may sometimes persist for months. Healthcare providers utilize this test to differentiate between acute and non-specific infections.