Primary infection by EBV causes infectious mononucleosis, usually a self-limiting disease in children and young adults. Infection with EBV can cause lymphoproliferative disorders including tumors. VCA-IgM is typically detectable at clinical presentation, then declines to undetectable levels within a month in young children and within 3 months in other individuals. VCA-IgG is typically detectable at clinical presentation, and persists for life. EBNA IgG typically appears during convalescence (3-4 months after clinical presentation) and remains detectable for life.