The viruses of the family Togaviridae are an extremely diverse group. There are two genera in the family: Alphavirus and Rubivirus. Rubivirus contains a single member (rubella virus) while there are 31 distinct members in the genus Alphavirus. The alphaviruses are typically transmitted by arthropods, primarily mosquitoes, whereas rubella virus is transmitted via respiratory secretions. The togaviruses have a nearly global distribution, cause a wide range of illness in humans and other animals, and have multiple mechanisms of pathogenesis. Interestingly, while the viruses are genetically extremely simple, the disease they cause ranges from mild or asymptomatic illness to severe polyarthralgia to encephalitis. This work summarises the current understanding of togavirus epidemiology, transmission and pathogenesis and describes current and future options for control of these pathogens.

Key Concepts

  • Togaviruses are an exceptionally diverse group of viruses with global distribution, a wide array of clinical disease, and distinct modes of transmission.
  • While sharing genome functional elements and general virion structure, viruses of the genera Rubivirus and Alphavirus have few other common features.
  • Alphaviruses are continuing to emerge in new ecological and epidemiological patterns.
  • Despite a widely available and efficacious vaccine, rubella virus persists as a global health concern.
  • More investigations are required to understand the pathogenesis of the vast range of alphaviruses.

Keywords: alphavirus; rubivirus; rubella virus; togavirus; viral epidemiology

Figure 1. Conserved functional motifs and their relative positions in alphavirus and rubivirus genomes.


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Powers, Ann M(Jun 2015) Togaviruses. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1002/9780470015902.a0023612]