What is the Ebola virus, and can it be stopped?

A bat suspected of being a carrier of the Ebola virus is prepared for a blood sample extraction in Bouake, Ivory Coast, in 2014.

Two doctors perform necropsies on bats at a makeshift laboratory.

A large colony of fruit bats takes flight out of the trees where they live in the village of Attienkru, outside Bouake, Ivory Coast. There's evidence that fruit bats may play a role in spreading the Ebola virus to other animals, who in turn spread it to humans.

Medical staff at the Hastings Ebola Treatment Centre in Sierra Leone escort a man in the throes of an Ebola-induced delirium back to the isolation ward from which he escaped.