Poxviruses
Humans, vertebrates, and arthropods serve as natural hosts.
Four genera of poxviruses may infect humans:
Orthopox: smallpox virus (variola), vaccinia virus, cowpox virus, monkeypox virus, rabbitpox virus;
Parapox: orf virus, pseudocowpox, bovine papular stomatitis virus; Yatapox: tanapox virus, yaba monkey tumor virus;
Molluscipox: molluscum contagiosum virus (MCV).
The most common are vaccinia and molluscum contagiosum, but monkeypox infections are rising (seen in west and central African rainforest countries). The similarly named disease chickenpox is not a true poxvirus and is actually caused by the herpesvirus varicella zoster.