This photograph depicted an individual who was holding a green monkey, Cercopithecus aethiops. The image was captured during a 1975 Centers for Disease Control and Prevention (CDC) Marburg investigation in what had been Rhodesia, now known as Zimbabwe. This species of monkey, which was also involved in the first, 1967 outbreak in Marburg, Germany, and in Zagreb, Yugoslavia, was being investigated as a possible vector for this Marburg outbreak. This CDC investigation occurred after two travelers were hospitalized with Marburg disease in Johannesburg. One of the travelers, referred to as Case #1, came into contact with an unknown vector while traveling through Zimbabwe, formerly Rhodesia. Case #1 then passed the Marburg virus to his traveling companion, referred to as Case #2, and a treatment nurse, Case #3.