Family: Caliciviridae

Genus: Salovirus

Distinguishing features

The strains in this genus form a distinct clade within the family Caliciviridae (Figure 4. Caliciviridae).  Viruses in this genus have only been detected in Atlantic salmon and belong to a single species, Nordland virus.

Virion

See discussion under family description. 

Genome organization and replication

The genome is 7.4 kb and similar other calicivirus genera, predicted to contain two ORFs. ORF1 encode a polyprotein with a predicted molecular mass of 256.5 kDa which is posttranslationally cleaved into the non-structural proteins and VP1. ORF2 encodes VP2 with a predicted molecular mass of 13.1 kDa. ORF2 overlaps the stop codon of ORF1 by 178 nt with a -1 frameshift. 

Biology

Saloviruses are novel caliciviruses that were isolated from heart tissue homogenate from Atlantic salmon with heart and skeletal muscle inflammation (Mikalsen et al., 2014). The virus has a high prevalence in farmed salmon and is found in fish suffering from several diseases and conditions and also in presumed healthy fish. After approximately 8 months (> 15 passages), the virus showed CPE in a fish (GF-1) cell line, and showed characteristic calicivirus-like particles by electron microscopy. The virus replicates in experimentally challenged salmon and causes a systemic infection. 

Species demarcation criteria

Not defined as there is only one species in the genus.