''Circovirus'' is a genus of
viruses
A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Viruses are found in almo ...
, in the family ''
Circoviridae
''Circoviridae'' is a family of DNA viruses. Birds and mammals serve as natural hosts. The family has two genera. Diseases associated with this family include: PCV-2: postweaning multisystemic wasting syndrome; CAV: chicken infectious anemia.
...
''. Birds (such as pigeons and ducks) and pigs serve as natural hosts, though dogs have been shown to be infected as well. Circoviruses are single stranded DNA (ssDNA) viruses. There are 70 species in this genus. Some members of this genus cause disease: PCV-1 is non pathogenic, while PCV-2 causes
postweaning multisystemic wasting syndrome
Porcine circoviral disease (PCVD), also known as porcine circovirus associated disease (PCVAD), is a disease seen in domestic pigs. This disease causes illness in Piglet (animal), piglets, with clinical signs including progressive loss of body co ...
(PMWS).
Structure
Viruses in ''Circovirus'' are non-enveloped, with icosahedrals capsids that have T=1 symmetry.
The diameter is around 17 nm. Genomes are circular and non-segmented.
The virions of Circoviruses are surprisingly small, with diameters ranging from 17 up to 22 nm.
Genome
Circovirus has a monopartite, circular, and ssDNA genome of between 1759 and 2319nt, making it possibly the virus of shortest genome size in mammal viruses. The virus replicates through an dsDNA intermediate initiated by the Rep protein. Two major genes are transcribed from open reading frame (ORF) 1 and 2. ORF1 encodes Rep and Rep' for initiation of rolling-circle replication; ORF2 encodes Cap, the only structural and most immunogenic protein forming the viral capsid.
Life cycle
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.
The virus is known to cause "immunosuppressive conditions" in animals that are infected; as well as having the ability to jump between species, creating difficulty in identifying the origin of infection.
Transmission routes are fecal-oral and parental.
Taxonomy
The genus contains the following species, listed by scientific name and followed by the exemplar virus of the species:
* ''Circovirus baizhenhe'',
White-naped crane circovirus 1
* ''Circovirus ban'',
Banfec circovirus 2
* ''Circovirus barbel'',
Barbel circovirus
* ''Circovirus bastao'',
Bat associated circovirus 4, also called
Tadarida brasiliensis circovirus 1
* ''Circovirus bear'',
Ursus americanus circovirus
* ''Circovirus bianfu'',
Bat associated circovirus 3, also called
Rhinolophus ferrumequinum circovirus 1
* ''Circovirus canary'',
Canary circovirus
* ''Circovirus canine'',
Canine circovirus
Canine circovirus (CaCV or DogCV), first isolated in 2012, is a small non-enveloped, icosahedral, single-stranded DNA virus that infects domestic dogs and wild canids exclusively. It is a member of the '' Circoviridae'' family and the genus ''Cir ...
* ''Circovirus catfish'',
European catfish circovirus, also called
Silurus glanis circovirus
* ''Circovirus chauvesouris'',
Bat associated circovirus 1
* ''Circovirus cia'',
Bat circovirus (BatACV12)
* ''Circovirus civet'',
Paguma larvata circovirus
The masked palm civet (''Paguma larvata''), also called the gem-faced civet or Himalayan palm civet, is a viverrid species native to the Indian subcontinent and Southeast Asia. It has been listed as least concern on the IUCN Red List since 2008 ...
* ''Circovirus daga'',
Rodent circovirus (RoACV6)
* ''Circovirus dever'',
Bream circovirus 1
* ''Circovirus duck'',
Duck circovirus
Duck circovirus (DuCV) is a type of virus found in ducks. Strains of the virus have predominantly been found in China, though strains have also been isolated from ducks in Germany and the United States.
Duck circovirus is a small nonenveloped vi ...
* ''Circovirus elk'',
Elk circovirus
The elk (: ''elk'' or ''elks''; ''Cervus canadensis'') or wapiti, is the second largest species within the deer family, Cervidae, and one of the largest terrestrial mammals in its native range of North America and Central and East Asia. T ...
* ''Circovirus eniyan'',
Human faeces associated circovirus
Humans (''Homo sapiens'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are Hominidae, great apes characterized by their Prehistory of nakedness and clothing ...
* ''Circovirus finch'',
Finch circovirus
The true finches are small to medium-sized passerine birds in the family Fringillidae. Finches generally have stout conical bills adapted for eating seeds and nuts and often have colourful plumage. They occupy a great range of habitats where the ...
* ''Circovirus gloton'',
Wolvfec circovius
* ''Circovirus gnaver'',
Rodent circovirus (RoACV5)
* ''Circovirus goose'',
Goose circovirus
A goose (: geese) is a bird of any of several waterfowl species in the family Anatidae. This group comprises the genera '' Anser'' (grey geese and white geese) and ''Branta'' (black geese). Some members of the Tadorninae subfamily (e.g., Egyp ...
* ''Circovirus gryzon'',
Bamboo rat circovirus
Bamboos are a diverse group of mostly evergreen perennial flowering plants making up the subfamily Bambusoideae of the grass family Poaceae. Giant bamboos are the largest members of the grass family, in the case of '' Dendrocalamus sinicus'' ...
* ''Circovirus gull'',
Gull circovirus
Gulls, or colloquially seagulls, are seabirds of the subfamily Larinae. They are most closely related to terns and Skimmer (bird), skimmers, distantly related to auks, and even more distantly related to waders. Until the 21st century, most gul ...
* ''Circovirus gyurgyalag'',
Bee-eater circovirus
* ''Circovirus hirat'',
Dipodfec virus UA04Rod_4537
* ''Circovirus human'',
Human circovirus 1
* ''Circovirus ialtag'',
Bat circovirus (BatACV10)
* ''Circovirus impundu'',
Chimpanzee faeces associated circovirus
* ''Circovirus kelawar'',
Bat associated circovirus 9
* ''Circovirus kiore'',
Rodent circovirus
* ''Circovirus kukwuria'',
Banfec circovirus 1
* ''Circovirus lepakko'',
Bat associated circovirus 7
* ''Circovirus lin'',
Equine circovirus 1
* ''Circovirus magu'',
Mongoose-associated circovirus Mon-1
* ''Circovirus mink'',
Mink circovirus
* ''Circovirus miztli'',
Sonfela circovirus 1
* ''Circovirus miztontli'',
Sonfela circovirus 2
* ''Circovirus morcego'',
Bat associated circovirus 8
* ''Circovirus mossi'',
Culex circovirus-like virus
* ''Circovirus naaleeli'',
Wigfec circovirus 1
* ''Circovirus parrot'',
Beak and feather disease virus
* ''Circovirus patkany'',
Brown rat circovirus 1
* ''Circovirus pato'',
Wigfec circovirus 2
* ''Circovirus penguin'',
Penguin circovirus
* ''Circovirus pichong'',
Tick circovirus
* ''Circovirus pigeon'',
Pigeon circovirus, also called
Columbid circovirus
* ''Circovirus pipistrello'',
Bat circovirus (BatACV13)
* ''Circovirus porcine1'',
Porcine circovirus 1
* ''Circovirus porcine2'',
Porcine circovirus 2
* ''Circovirus porcine3'',
Porcine circovirus 3
* ''Circovirus porcine4'',
Porcine circovirus 4
* ''Circovirus python'',
Black-headed python circovirus 1
* ''Circovirus ratpenat'',
Bat associated circovirus 6
* ''Circovirus raven'',
Raven circovirus
* ''Circovirus razbora'',
Pseudorasbora circovirus 1
* ''Circovirus roditore'',
Rodent circovirus (RoACV3)
* ''Circovirus rongeur'',
Rodent circovirus (RoACV1)
* ''Circovirus rosegador'',
Rodent circovirus (RoACV4)
* ''Circovirus saguzarra'',
Bat associated circovirus 5
* ''Circovirus siksparnis'',
Bat circovirus (BatACV11)
* ''Circovirus starling'',
Starling circovirus
* ''Circovirus swan'',
Swan circovirus
* ''Circovirus tetning'',
Werosea circovirus
* ''Circovirus torpegem'',
Little bittern circovirus
* ''Circovirus tzinaka'',
Eumops bonariensis associated circovirus 1
* ''Circovirus vleermuis'',
Bat associated circovirus 2
* ''Circovirus wesa'',
Calfel virus LSF45_cir359
* ''Circovirus whale'',
Beaked whale circovirus
* ''Circovirus yaa'',
Avian-like circovirus
* ''Circovirus zebrafinch'',
Zebra finch circovirus
References
External links
Viralzone: CircovirusICTVCircovirus – MicrobeWiki
{{Taxonbar, from=Q5121560
Circoviridae
Virus genera