infections
Overview of Herpesvirus Infections
Introduction
Some common viral infections are caused by a group of viruses called herpesviruses. Eight different types of herpesviruses infect people: Three herpesviruses— Herpes Simplex Virus (HSV) Infections type 1, herpes simplex virus type 2, and varicella-zoster virus (herpesvirus type 3, which causes Epstein-Barr virus (herpesvirus type 4) causes Infectious Mononucleosis and may be involved in certain cancers (such as Cytomegalovirus (CMV) Infection (herpesvirus type 5) is a cause of serious infections in newborns and in people with a weakened Human herpesviruses 6 and 7 cause a childhood infection called Roseola Infantum . Human herpesvirus 8 causes certain cancers ( Kaposi Sarcoma and some types of lymphoma), in people with a weakened immune system such as people with All of the herpesviruses cause lifelong infection because the virus remains dormant in some of the cells it infects. All of the herpesviruses cause lifelong infection because the virus remains within its host cell in an inactive (dormant or latent) state. Sometimes the virus reactivates and produces further episodes of disease. Symptoms from reactivation can be different than the symptoms of the initial infection. Reactivation may occur rapidly or many years after the initial infection. (See also Overview of Viral Infections .) 