Orthopoxvirus is a genus of poxviruses that includes many species isolated from mammals, such as Camelpox virus, Cowpox virus, Ectromelia virus(mousepox), Monkeypox virus, and Volepox virus. The most famous member of the genus is Variola virus, which causes smallpox. It was eradicated using another orthopoxvirus, Vaccinia virus, as a vaccine.