[3] TAHV is maintained in an enzootic life cycle involving several species of mosquito vectors, with hares, rabbits, hedgehogs, and rodents serving as amplifying hosts.

[1] Human TAHV infections generally occur in summer and early fall, with symptoms of fever, headache, malaise, conjunctivitis, pharyngitis, and nausea.

Human infections are common in endemic areas, with neutralizing antibodies present in 60 to 80% of the elderly population.

RT-PCR methods are under development to detect viral RNA in cerebrospinal fluid samples of patients with encephalitis.

The three segments are designated by their size, small (S), medium (M), and large (L) and are complexed with nucleoprotein to form three separate nucleocapsids.