Circovirus is a genus of viruses, in the family Circoviridae. Birds (such as pigeons[1] and ducks[2]) and pigs[3] serve as natural hosts, though dogs have been shown to be infected as well.[4] It is a single stranded DNA virus (ssDNA). There are 49 species in this genus. Some members of this genus cause disease: PCV-1 is non pathogenic, while PCV-2 causes postweaning multisystemic wasting syndrome (PMWS).[5][6]
The following species are recognized:
Viruses in Circovirus are non-enveloped, with icosahedral and round geometries, and T=1 symmetry. The diameter is around 17 nm. Genomes are circular and non-segmented.[5]
The virions of Circoviruses are surprisingly small, with diameters ranging from 17 up to 22 nm.[7]
Viral replication is nuclear. Entry into the host cell is achieved by penetration. Replication follows the ssDNA rolling circle model. DNA templated transcription, with some alternative splicing mechanism is the method of transcription. The virus exits the host cell by nuclear egress, and nuclear pore export. Birds and pigs serve as the natural host. Transmission routes are fecal-oral and parental.[5]
Circovirus is a genus of viruses, in the family Circoviridae. Birds (such as pigeons and ducks) and pigs serve as natural hosts, though dogs have been shown to be infected as well. It is a single stranded DNA virus (ssDNA). There are 49 species in this genus. Some members of this genus cause disease: PCV-1 is non pathogenic, while PCV-2 causes postweaning multisystemic wasting syndrome (PMWS).
