Group Group IV ((+)ssRNA) Family Roniviridae | Rank Genus | |
Similar Nidovirales, Tetraviridae, Mesoniviridae, Corticovirus, Ophioviridae | ||
Okavirus is a genus of viruses in the order Nidovirales, in the family Roniviridae. Okaviruses infect crustaceans, mostly prawns. There is currently only one species in this genus: the type species Gill-associated virus. Diseases associated with this genus include: GAV: reddening, biofouling with exoparasites, emaciation, massive mortality; YHV: yellow head, arrest of feeding. massive mortality. The name is derived from the 'Oka' or lymphoid organ in which the viruses are commonly detected and in which pathology occurs during acute infections. Lymphoid organs are anatomical structures common to penaeid shrimp.
Contents
Taxonomy
Group: ssRNA(+)
Two virus strains are recognized in this genus: Gill-associated virus and yellowhead virus. Both species were isolated from prawns.
Structure
Viruses in Okavirus are enveloped, with bacilliform geometries, and helical symmetry. The diameter is around 20-30 nm. Genomes are linear and non-segmented, around 26kb in length.
Life Cycle
Entry into the host cell is achieved by attachment to host receptors, which mediates endocytosis. Replication follows the positive stranded RNA virus replication model. Positive stranded RNA virus transcription is the method of transcription. Crustaceans and mostly prawns serve as the natural host. Transmission routes are ingestion.