Circovirus

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. 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 (PMWS).