Herpesviridae

A heterogeneous family of morphologically similar viruses, all of which contain double-stranded DNA and which infect man and a wide variety of other vertebrates. Infections produce type A inclusion bodies; in many instances, infection may remain latent for many years, even in the presence of specific circulating antibodies. Virions are enveloped, ether-sensitive, and vary up to 200 nm in diameter; the nucleocapsids are 100 nm in diameter and of icosahedral symmetry, with 162 capsomeres. The family is subdivided into 3 subfamilies Alphaherpesvirinae, Betaherpesvirinae, and Gammaherpesvirinae, and includes herpes simplex virus, varicella-zoster virus, cytomegalovirus, and EB virus (all of which infect humans), pseudorabies virus of swine, equine rhinopneumonitis virus, infectious bovine rhinotracheitis virus, canine herpesvirus, B virus of Old World monkeys, several viruses of New World monkeys, virus III of rabbits, infectious laryngotracheitis virus of fowl, Marek disease virus of chickens, Lucké tumor virus of frogs, and many others.

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Her·pes·vi·ri·dae -'vir-ə-.dē n pl a family of double-stranded DNA viruses that consist of a spherical virion having the DNA packaged in a liquid crystalline array in a central core surrounded by an icosahedral capsid, an amorphous layer of proteins, and an envelope consisting of a lipid bilayer closely associated with the amorphous protein layer and that include the cytomegalovirus and Epstein-Barr virus and the causative agents of chicken pox, equine coital exanthema, herpes simplex, infectious bovine rhinotracheitis, infectious laryngotracheitis, malignant catarrhal fever, Marek's disease, pseudorabies, rhinopneumonitis, roseola infantum, and shingles see simplexvirus, varicellovirus

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Her·pes·vi·ri·dae (hur″pēz-viґrĭ-de) the herpesviruses: a family of DNA viruses having a virion 102–200 nm in diameter consisting of four components: a lipid bilayer envelope with surface projections, a tegument of amorphous material, an icosahedral nucleocapsid with 162 prismatic capsomers, and a protein spool on which the DNA is wrapped. The genome consists of a single molecule of linear double-stranded DNA (MW 70–150 Ч 10⁶, size 124–235 kbp). Viruses contain at least 20 structural polypeptides and are sensitive to lipid solvents, heat, and extremes of pH. Replication occurs in the nucleus and the envelope is acquired by budding through the inner lamella of the nuclear membrane; virions are released by transport via the endoplasmic reticulum to the cell membrane. Persistence for the lifetime of the host is common and some herpesviruses induce neoplasia. There are three subfamilies: Alphaherpesvirinae, Betaherpesvirinae, and Gammaherpesvirinae. A large number of herpesviruses have not yet been assigned to a subfamily or genus.