Coltiviruses and Seadornaviruses in North America, Europe, and Asia

Houssam Attoui; Fauziah Mohd Jaafar; Philippe de Micco; Xavier de Lamballerie


Emerging Infectious Diseases. 2005;11(11) 

In This Article

Abstract and Introduction

Coltiviruses are tickborne viruses of the genus Coltivirus. The type species, Colorado tick fever virus (from North America), has been isolated from patients with flulike syndromes, meningitis, encephalitis, and other severe complications. Another coltivirus, Eyach virus, has been isolated from ticks in France and Germany and incriminated in febrile illnesses and neurologic syndromes. Seadornaviruses are endemic in Southeast Asia, particularly Indonesia and China. The prototype virus of the genus, Banna virus (BAV), has been isolated from many mosquito species, humans with encephalitis, pigs, and cattle. Two other seadornaviruses, Kadipiro and Liao Ning, were isolated only from mosquitoes. The epidemiology of seadornaviruses remains poorly documented. Evidence suggests that BAV is responsible for encephalitis in humans. Infection with BAV may be underreported because it circulates in regions with a high incidence of Japanese encephalitis and could be misdiagnosed as this disease.

Vertebrate viruses belonging to the family Reoviridae and having 12-segmented dsRNA genomes at one time were classified in the genus Coltivirus (Colorado tick virus [CTFV]). At the time the genus was created, it included tickborne and mosquitoborne viruses. Presently, the genus Coltivirus contains only CTFV, California hare coltivirus (CTFV-Ca), which is considered a serotype of CTFV, Eyach virus (EYAV), which is distinct from CTFV, and Salmon River virus (SRV), which may be a serotype of both CTFV and CTFV-Ca. Alternatively, analysis of sequence data and antigenic properties of the mosquitoborne viruses led to their reassignment to a new genus designated Seadornavirus (Southeast Asian dodeca RNA virus).[1,2]