Genus: Cosavirus

Distinguishing features

Virion

Morphology

Virus has not yet been isolated.

Nucleic acid

Length of genome [{Holtz et al., 2008:19102772RJOHTXHoltz et al., 2008, Identification of a novel picornavirus related to cosaviruses in a child with acute diarrhea, Virol J, 5, 159RJOMREFKapoor et al., 2008:19033469RJOHTXKapoor et al., 2008, A highly prevalent and genetically diversified Picornaviridae genus in South Asian children, Proceedings of the National Academy of Sciences, USA 105, 51, 20482-7RJOMREFBlinkova et al., 2009:19794058RJOHTXBlinkova et al., 2009, Frequent detection of highly diverse variants of cardiovirus, cosavirus, bocavirus, and circovirus in sewage samples collected in the United States, J Clin Microbiol, 47, 11, 3507-13RJOMREFCotten et al., 2014:24695106RJOHTXCotten et al., 2014, Full genome virus detection in fecal samples using sensitive nucleic acid preparation, deep sequencing, and a novel iterative sequence classification algorithm, PLoS One, 9, 4, e93269RJOMREFKapusinszky et al., 2012:22615791RJOHTXKapusinszky et al., 2012, Genetic diversity of the genus Cosavirus in the family Picornaviridae: a new species, recombination, and 26 new genotypes, PLoS One, 7, 5, e36685}]: c. 7,632-7,802 nt (5'-UTR: up to 1,361 nt; ORF: 6,366-6,402 nt; 3'-UTR: 75-93 nt). The location of the cre has not been identified. 

Genome organization and replication

Genome layout:

VPg+5'UTR^IRES-II[1A-1B-1C-1D-2A1^npgp/2B-2C/3A-3B-3C-3D]3'UTR-poly(A)

The deduced polyproteins have lengths of 2,113-2,133 amino acids. There is no L protein. 2A is a short FMDV-like polypeptide (NPG¯P). Sequence data (e.g., JN867757, KM516909) suggest interspecies recombination [{Kapusinszky et al., 2012:22615791RJOHTXKapusinszky et al., 2012, Genetic diversity of the genus Cosavirus in the family Picornaviridae: a new species, recombination, and 26 new genotypes, PLoS One, 7, 5, e36685}]. 

Biology

Known natural hosts are humans and pigs. Viral RNA was detected in faeces and pharyngeal swabs of diseased and clinically healthy humans and pigs.

Species demarcation criteria

Members of a species of the genus Cosavirus:

• share greater than 65% aa identity in P1,
• share greater than 90% aa identity in 2C + 3CD,
• share a common genome organization.

The divergence (number of differences per site between sequences) of known cosaviruses ranges from 0.4-0.53 for P1 and 0.22-0.37 for 3CD.

Sequence data of capsid protein-encoding gene regions indicate at least 35 types within these species (CoSV-A1 to -A25, CoS-V-B1, tentative CoSV-C1, CoSV-D1 to -D5, CoSV-E1, -E2, CoSV-F1).

Member Species

Virus names, the choice of exemplar isolates, and virus abbreviations, are not official ICTV designations.
Download GenBank/EMBL query for sequences listed in the table here.

Establishment of Cosavirus C is pending due to incomplete virus sequences.

Derivation of names

Cosa-: from common stool-associated