Togaviruses

Categorization
Genome: RNA Virus, Positive ssRNA Virus Structure: Enveloped Virus
Overview
  • Togaviruses represent a family of nearly 30 structurally-related viruses which are transmitted via mosquito vector and tend to cause encephalitis. The entire family is discussed together although different togavirus species have different geographical ranges. Note that Rubella Virus is structurally similar to Togaviruses but because it is not transmitted by arthropod-vector, it is not considered here.
Transmission
  • Togaviruses are spread to humans via mosquitoes who have taken a previous blood meal from an infected mammal or bird. Because these viruses can cause similar pathologies in horses, their names often reflect their capacity for equine infection. Different viruses possess different geographic ranges and their names reflect this fact. For example, Western Equine Encephalitis tends to occur in the Western US, Eastern Equine Encephalitis tends to occur in the Eastern US, Venezuelan Equine Encephalitis tends to occur in Southern America.
Clinical Consequences
  • In general, togavirus infection results in encephalitis which is accompanied by constitutional symptoms indicative of an infection.