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The first filovirus was recognized in 1967 when a number of laboratory workers in Germany and Yugoslavia, who were handling tissues from green monkeys, developed hemorrhagic fever. A total of 31 cases and seven deaths were associated with these outbreaks. The virus was named after Marburg, Germany, the site of one of the outbreaks.
After the initial outbreaks, the virus disappeared. It did not reemerge until 1975, when a traveler, most likely exposed in Zimbabwe, became ill in Johannesburg, South Africa. The virus was transmitted there to his traveling companion and a nurse. A few sporadic cases of Marburg hemorrhagic fever have been identified since that time.
Ebola virus was first identified in 1976 when two outbreaks of Ebola hemorrhagic fever (Ebola HF) occurred in northern Zaire (now the Democratic Republic of Congo) and southern Sudan. The outbreaks involved what eventually proved to be two different subtypes of Ebola virus; both were named after the nations in which they were discovered. Both viruses showed themselves to be highly lethal, as 90% of the Zairian cases and 50% of the Sudanese cases resulted in death.
In 1989, a new Ebola virus subtype was identified in imported cynomolgous macaques (an Asiatic monkey, Macacca fascicularis) during an outbreak in a primate quarantine facility in the United States. This subtype causes severe illness in primates, but it did not appear to cause illness in the few humans infected. Another subtype, named Ivory Coast, was identified in a patient infected in that country in 1994. This incident provided the first evidence of Ebola virus infection in West Africa.
Between 1976 and 1995, Ebola virus appeared sporadically in Africa, with small to mid-size outbreaks confirmed between 1976 and 1979. In 1995, a large epidemic of Ebola HF occurred in Kikwit, Zaire. Of the 316 people known to have contracted the disease, 80% died. Smaller outbreaks were identified in Gabon between 1994 and 1996(taken from the CDC Information site )