Monkeypox is a relatively rare disease that was first detected in monkeys in Africa in 1958 and resembles smallpox in terms of the skin lesions (pox) seen in humans as part of the physical findings and also because the cause is a virus that is closely related to the smallpox (variola) virus. Monkeypox, smallpox, cowpox, and vaccinia viruses all belong to the same family of viruses, the Poxviridae. Monkeypox belongs to same genus (Orthopoxvirus) as smallpox. The disease is different from smallpox. Monkeypox may be transferred from animals to people (or person to person) and has far less mortality (death rate) than smallpox had. Monkeypox virus is endemic in rodent populations in Africa. Smallpox did not infect any endemic animal population. The press and bloggers have occasionally tried to link monkeypox to other diseases such as mad cow disease, Ebola, leprosy, yellow fever, and other viral and immunological diseases, but there is no scientific evidence for this.