eyach virus eyach virus eyach virus (eyav) is a viral infection (genus coltivirus) in the reoviridae family transmitted by a tick vector. it has been isolated from ixodes ricinus and i. ventalloi ticks in europe. eyach coltivirus virus classification (unranked): virus realm: riboviria kingdom: orthornavirae phylum: duplornaviricota class: resentoviricetes order: reovirales family: reoviridae genus: coltivirus species: eyach coltivirus transmission and clinical syndromes eyach virus is acquired by tick bite. the tick gets infected after a blood meal from a vertebrate host, which is suspected to be the european rabbit o. cunniculus. eyach virus has been linked to tick-borne encephalitis, as well as polyradiculoneuritis and meningopolyneuritis, based on serological samples of patients with these neurological disorders.