CD8A and Epstein-Barr virus infection: Although the total number of CD8+ T cells is not significantly raised in children with asymptomatic primary EBV infection, EBV-specific CD8+ T cells are highly activated and can control the infection without causing excessive expansion (14, 15), confirming that cytotoxic lymphocytes are the cornerstone of EBV-specific immune control, and that IM is an immunopathologic condition.