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I’m kinda like herpes, I just keep coming back.
George Carlin
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Overview
The Herpesviridae is composed of large, enveloped, double-stranded DNA viruses. There are eight known human herpesviruses (HHVs) and a very large number of animal herpesvirsues. The HHVs include: herpes simplex virus-1 (HSV-1) and HSV-2, which cause facial and genital lesions; varicella-zoster virus (VZV), which causes chickenpox and later in life can reactivate to cause shingles; Epstein-Barr virus (EBV), an infectious cause of mononucleosis as well as Burkitt lymphoma (BL) among other B-cell lymphomas; cytomegalovirus (CMV) can also cause mononucleosis symptoms in adults, and is a leading cause of congenital blindness; HHV types 6 and 7 (HHV-6 and HHV-7), which cause roseola in infants; and Kaposi Sarcoma (KS)-associated herpesvirus (KSHV), also known as HHV-8 (Table 14–1). In addition, the simian herpesvirus, herpes B virus, has occasionally caused lethal human disease in primate center workers. All herpesviruses establish lifelong latent infections in their hosts with periodic reactivation events.
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✺ Large, enveloped, double-stranded DNA viruses
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Eight HHVs cause a range of diseases
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HERPESVIRUSES: GROUP CHARACTERISTICS
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All herpesviruses are morphologically similar, with an overall size of 180 to 200 nm. An example of a HSV virion is shown in Figure 14–1 as a representative virion structure for herpesviruses. The linear, double-stranded DNA genome and core proteins are encapsidated by an icosahedral capsid. The capsid is surrounded by the tegument, a relatively amorphous protein-filled region unique to herpesviruses. The tegument contains viral proteins and enzymes that play a ...