Genus: Pasivirus

Genus: Pasivirus

Distinguishing features

The genus is distinguished on the basis of genetic characters.



No details are available on the morphology of virions.

Nucleic acid

Genome (Sauvage et al., 2012, Yu et al., 2013Boros et al., 2015a): c. 6,938 nt (5′-UTR: c. 420 nt; ORF: c. 6,402 nt; 3′-UTR: 136 nt). The location of the cre has not been identified. 

Genome organization and replication

Genome layout:


The deduced polyprotein is of c. 2,133 aa. There is no L protein. The 1AB protein remains uncleaved. The 2A1 protein has an NPG↓P sequence motif; the function of 2A2 is unknown. The 3Dpol of all known pasiviruses has the motif ASG rather than PSG. 


The natural host is likely the domestic pig (Sus scrofa). No virus has been isolated. Viral RNA has been detected in faeces of pigs. Four types are distinguished by means of phylogenetic analysis.

Derivation of names

Pasivirus: from parecho sister-clade

Species demarcation criteria

There is only a single species in the genus.

Member species

Exemplar isolate of the species
SpeciesVirus nameIsolateAccession numberRefSeq numberAvailable sequenceVirus Abbrev.
Pasivirus Apasivirus A1; swine pasivirusswine/France/2011JQ316470NC_018226Complete genomePaV-A1
Pasivirus Apasivirus A2PVL-CHN (pig/China/2010)JX491648Complete genomePaV-A2
Pasivirus Apasivirus A3swine/Zsana1/2013/HUN (pig/Hungary/2013)KM259923Complete genomePaV-A3
Pasivirus Apasivirus A4Ger/L01061-K07/15-03/2015LT898422Complete genomePaV-A4

Virus names, the choice of exemplar isolates, and virus abbreviations, are not official ICTV designations.