Poxviridae are family of large complex DNA viruses, including the vaccinia and variola viruses, that are pathogenic to humans and animals and have an affinity for skin tissue. Smallpox is in the family Poxviridae.
Group I (dsDNA)
Four genera of poxviruses may infect humans: orthopox, parapox, yatapox, molluscipox. Orthopox: variola virus, vaccinia virus, cowpox virus, monkeypox virus, smallpox (eradicated); Parapox: orf virus, pseudocowpox, bovine papular stomatitis virus; Yatapox: tanapox virus, yaba monkey tumor virus; Molluscipox: molluscum contagiosum virus (MCV).