Transmission electron microscopic (TEM) image of Colorado tick fever virus

Colorado tick fever (CTF) virus is a member of the family Reoviridae, subfamily Spinareovirinae, genus Coltivirus. CTF virus contains 12 segments of double-stranded RNA. The virus genome is relatively large compared to other arthropod-borne viruses at ~29,000 base pairs. The virus has an icosahedral capsid structure and a diameter of 80 nm.