Have you ever heard of Ebola? Of course, you have… It’s one of the scariest diseases out there. And one of the deadliest. It kills between 44 and 90 percent of the people it infects. Why is there such a big range? What makes some Ebola infections deadlier than others? To answer these questions, we analyzed thousands of Ebola cases reported during the 2013-2016 Ebola outbreak in West Africa. We wanted to know what factors helped some of the patients survive. We found that age is a really important factor determining if the patient survived or not. That is because young adults are more likely to survive than others. We also analyzed the proportion of patients who survived by district and by hospital and found that these proportions did not always match our expectations: they were either a lot higher or a lot lower.