Togaviridae

A family of viruses that includes two genera : Alphavirus, which includes eastern equine encephalitis, western equine encephalitis, and Venezuelan equine encephalitis virus, and Rubivirus, the rubella virus. Virions are 70 nm in diameter, enveloped, and ether-sensitive; the capsid is of icosahedral symmetry, containing single-stranded positive sense RNA.

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To·ga·vi·ri·dae .to-gə-'vir-ə-.dē n pl a family of single-stranded RNA viruses that have a spherical virion about 70 nanometers in diameter and that include the causative agents of German measles and the three equine encephalomyelitides see alphavirus

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To·ga·vi·ri·dae (to″gə-virґĭ-de) the togaviruses, a family of RNA viruses having a spherical virion 60–70 nm in diameter consisting of a lipid-containing envelope, with five peplomers, surrounding an icosahedral nucleocapsid. The genome consists of a single molecule of polyadenylated positive-sense single-stranded RNA (MW 4 Ч 10⁶, size 9.7–11.8 kb). Viruses contain three or four major structural proteins and are sensitive to lipid solvents, detergents, and ultraviolet radiation. Replication occurs in the cytoplasm and assembly occurs by budding through the plasma membrane. There are two genera: Alphavirus and Rubivirus.