The most mild strain of Ebola killed 40%, the nastiest 90%, and so far, with the best available numbers this one is killing about 70%.
We say our better medicine is capable of saving us, and it has done well, but it can only handle so many cases.
There are 23 level 4 beds in the country, and even with our ability to improvise, the mortality rate here would jump significantly in the event that the system is overwhelmed--which likely would only take a few hundred cases.