I do understand what a mortality rate is. And nobody knows what ebola's mortality rate is in the United States - at the moment, it's hovering at exactly 0%. It's certainly nowhere near 55%. Mortality rates in any event are just one piece of the puzzle - because influenza is so incredibly infectious it manages to kill far more people. In general, diseases with the highest mortality rates generally pose less of a risk to the public at large because they burn out quickly.
Mortality rate for the Zaire strain of Ebola is not zero anywhere in the world. Learn what statistics are, you are using lies and half truths/