There is an interesting article about where Ebola came in Life Science: "Where Did Ebola Come From? - Live Science"/Health Ebola

Scientists in this article think the Ebola virus lives in bats, but the bats don't get sick. They think maybe people first got Ebola virus when someone caught and killed some bats, maybe to make bat soup, which is a popular food.

Ebola virus attacks people's immune cells and damages their blood vessels. Our immune systems only work part of the time. One thing that helps the immune system is if our bodies have gotten a little bit of something that causes a disease. Then our bodies can make antibodies against whatever causes the disease, and the antibodies can fight the disease if it comes back, too.

The only outbreak of Ebola this year was in the Congo in Africa, and it ended on July 2, 2017. 6 or 8 people got the infection, and 4 died.

Ebola virus disease is a severe, often fatal illness. The virus was first identified in 1976 in Africa and scientists think it was spread to humans through contact with fruit bats. Humans can spread the virus by sharing bodily fluids, and outbreaks occur when sick people are in close contact with other uninfected people. Our immune system has a variety of ways to fight viral infections at different stages of infection. The problem is that Ebola interferes with the proper functioning of our immune system and so our bodies have a hard time fighting the infection. Luckily, scientists have been developing a vaccine for Ebola, and trials have shown it is highly effective.