Initially, arboviruses were given the name of the illness which they caused, e.g., bluetongue (a disease of sheep), yellow fever, dengue and Chikungunya (which breaks the bones); later, it became necessary to add a geographic connotation to differentiate the causative virus, e.g., eastern or western equine encephalitis virus. The vector/vertebrate interaction gives unique epidemiologic characteristics to the impact of arboviruses on human and domestic animal communities. This impact may be revealed by a review of the clinical importance of the diseases, the risks of infection, the impact on the community, the intervention of health services, and the future trends of these diseases. Certain arboviruses possess a marked neurotropism. A prodromal phase, marked by some of the systemic symptoms, may or may not precede the onset of neurologic signs. The full-blown encephalitic syndrome comprises a sudden rise of fever, vomiting, stiffness of the neck, dizziness, drowsiness, disorientation, confusion, and progression to stupor and coma.