The genus is distinguished on the basis of genetic characters.
No details are available on the morphology of virions.
Genome (Holtz et al., 2008, Kapoor et al., 2008a, Blinkova et al., 2009, Cotten et al., 2014, Kapusinszky et al., 2012): 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
The deduced polyproteins are of 2,113–2,133 amino acids. There is no L protein. 2A is a short foot-and-mouth disease virus-like polypeptide (NPG↓P). Sequence data (e.g., JN867757, KM516909) suggest interspecies recombination (Kapusinszky et al., 2012).
Known natural hosts are humans and pigs. No virus has been isolated. Viral RNA was detected in faeces and pharyngeal swabs of diseased and clinically healthy humans and pigs. Sequence data of capsid protein-encoding gene regions indicate at least 35 types within the species (CoSV-A1 to -A25, CoS-V-B1, tentative CoSV-C1, CoSV-D1 to -D5, CoSV-E1, -E2, CoSV-F1).
Derivation of names
Cosavirus: from common stool-associated virus
Species demarcation criteria
Members of a species of the genus Cosavirus:
- are less than 35% divergent in P1 aa sequence
- are less than 10% divergent in 2C + 3CD aa sequence
- share a common genome organization
The divergence (number of differences per site between sequences) of different cosavirus species ranges from 0.4–0.53 for P1 and 0.22–0.37 for 3CD.
Related, unclassified viruses
cosavirus C [hu/5152]
Virus names and virus abbreviations are not official ICTV designations.
* partial genome
The virus cosavirus C likely belongs to an additional species, but remains unclassified because only an incomplete virus sequence is available.