Forty years ago, Ebola was just the name of a river. The first case of Ebola Appeared in 1976 in what is now the Democratic Republic of Congo (then Zaire). The virus got its name from the river which flowed not too far from the village hospital.
Ebola virus is a zoonosis, meaning an animal infection transmissible to humans. The animal in which a zoonosis lives its customary existence, discreetly, over the long term, and without causing symptoms, is called a reservoir host.
The reservoir host for Ebola are still unknown but fruit bats are one of the main suspects.