The Yaba monkey tumor virus is a type of poxvirus.[1][2] The first case of the virus was obtained from a colony of rhesus monkeys in Yaba, Lagos, Nigeria.[3][4] The virus caused the formation of tumors on the bodies of the monkeys. From these tumors the virus was isolated and determined to be its own species of virus. It is a species of the Yatapoxvirus genus and is closely related to the tanapox. The virus gets its name from the suburb of Yaba, Lagos.