togavirus, any of three genera of arthropod-borne viruses (arboviruses) of the family Togaviridae. Flaviviruses, once considered to be of the Togaviridae, are now designated as members of a separate family, Flaviviridae.
The togavirus genera are Alphavirus, which is carried by mosquitoes, and Rubivirus, which contains rubella, or German measles, virus. Some Alphavirus species produce severe encephalitis in humans. Horses also may be severely or fatally infected, by equine encephalitis. Rubivirus is immunologically distinct from the other togaviruses.