Overview of immunopathology of chronic active herpesvirus infection.

Chronic latent infection with human herpesvirus is common; antibody prevalence in the general population varies from 40 to above 95%, for herpesvirus-6 at about 20%. Reactivation occurs in 5-20% of healthy persons. If reactivation coincides with impaired host response, chronic active infection may ensue. Chronic active infection by certain members of the Herpesviridae such as EBV, CMV and HHV-6 is prone to being complicated by autoimmune diseases and atypical lymphoproliferation. Its diagnosis is occasionally rendered difficult by a variety of immunologic interference factors, thus final evaluation must result from clinical, immunopathological and virological cooperation.