Family: Caliciviridae

Genus: Recovirus

Distinguishing features

The strains in this genus form a distinct clade within the family Caliciviridae (Figure 4. Caliciviridae). 

Virion

See discussion under family description. 

Genome organization and replication

The complete genome of recoviruses is 6.7 kb and like noroviruses is organized into three ORFs. ORF1 encodes a polyprotein that is post-translationally cleaved into six nonstructural proteins, ORF2 encodes the major capsid protein (VP1) with a calculated molecular mass of 57.9 kDa, and ORF3 encodes a minor capsid protein (VP2) with a calculated molecular mass of 22.8 kDa. Recoviruses can phylogenetically be grouped in at least 3 different genogroups, GI, GII and GIII, and GI strains can be further separated into three genotypes (GI.1–GI.3) with significant variation of the overlap of ORFs and frame shift among the genotypes. 

Biology 

The exemplar isolate of the type species Recovirus A, Tulane virus, was discovered in stool samples collected from juvenile macaques housed at the Tulane National Primate Research Center (TNPRC) (Farkas et al., 2008). Several strains have been detected in stools of young children which constitute a separate genotype (GIII) (Smits et al., 2012). 

Species demarcation criteria 

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

Related, unclassified viruses

Virus names and virus abbreviations are not official ICTV designations.