infectious diseases
Overview of Herpesvirus Infections
Introduction
Eight types of herpesviruses infect humans (see table). After initial infection, all herpesviruses remain latent within specific host cells and may subsequently reactivate. Clinical syndromes due to primary infection can vary significantly from those caused by reactivation of these viruses. Herpesviruses do not survive long outside a host; thus, transmission usually requires intimate contact. In people with latent infection, the virus can reactivate without causing symptoms; in such cases, asymptomatic shedding occurs and people can transmit infection. Despite the fact that the herpesviruses are genetically and structurally similar, they cause a wide array of generally non-overlapping clinical syndromes. In contrast to other herpesviruses that are not known to cause malignancy, Epstein-Barr virus (EBV) and human herpesvirus type 8 (HHV-8), also known as Kaposi sarcoma–associated herpesvirus (KSHV), can cause certain cancers. Roseola Infantum is a childhood disease caused by herpesvirus 6 (and sometimes 7). 