Question: What caused the Ebola outbreak?

Robert Hampson answered on 21 Nov 2014:

Ebola is caused by a filovirus (a long virus that looks like a string). There are three known groups of filoviruses: the Ebola viruses, the Marburg viruses and the Cueva virus.

Ebola normally infects fruit bats. It can also infect primates, pigs and humans if they come into contact with the bats or other infected hosts. Normally, Ebola hot spots are in countries like Congo. In these countries, they often eat bushmeat (dead wild animals including bats and primates) so there is the occasional Ebola infection. However, in these countries they are used to this occurrence and they know what to do about it. So generally an infection might cause only 3 or 4 people to get sick because they respond well.

However, the current outbreak is located mostly in Sierra Leone, Guinea and Liberia. This is not normally a common place for Ebola infections. Therefore, the population was underprepared, they could not spot an Ebola infection, nor did they know how to respond to it. This allowed one or two initial infections to snowball into a massive problem. Furthermore, funeral practices in the area often involve close contact with dead relatives. This further spread the disease. Once there was a significant pool of infected individuals, it was much easier for the disease to spread.

We hope with education and better medical care, that the disease will slowly go away again.