Poxviridae

A family of large complex viruses, with a marked affinity for skin tissue, that are pathogenic for humans and other animals. Virions are large, up to 250 × 400 nm, and enveloped (double membranes). Replication occurs entirely in the cytoplasm of infected cells. Capsids are of complex symmetry and contain double-stranded DNA (MW 160 × 10⁶), the nucleoprotein antigen being common to all members of the family. A number of genera are recognized, including: Orthopoxvirus, Avipoxvirus, Capripoxvirus, Leporipoxvirus, and Parapoxvirus.

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Pox·vi·ri·dae .päks-'vir-ə-.dē n pl a family of large brick-shaped or ovoid double-stranded DNA viruses that have a fluffy appearance caused by a covering of tubules and threads and that include the vaccinia virus and the causative agents of cowpox, fowl pox, molluscum contagiosum, monkeypox, mousepox, myxomatosis of rabbits, sheep pox, smallpox, sore mouth of sheep, and swine pox

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Pox·vi·ri·dae (poks″virґĭ-de) the poxviruses: a family of DNA viruses having a brick-shaped or ovoid virion 220–450 Ч 140–260 nm consisting of an envelope containing lipid and tubular or globular protein structures surrounding a DNA-containing core and one or two lateral bodies. The genome consists of a single molecule of double-stranded DNA (size 130–375 kbp). Viruses contain over 100 proteins; some are ether-resistant while others are ether-sensitive. Replication and assembly occur in the cytoplasm; virions are released by cell destruction or budding. Host range is narrow and transmission is by fomites, airborne particles, arthropod vectors, or contact. There are two subfamilies: Chordopoxvirinae (poxviruses of vertebrates) and Entomopoxvirinae (poxviruses of insects).