Ebola can incubate 1 to 3 weeks before any symptoms arise in which time someone could travel around the world

Ebola isn’t nearly as contagious as, say, measles or influenza. It is transmitted only through bodily fluids after the fever and other symptoms have occurred. But the incubation period, after infection and before the person becomes symptomatic, typically lasts about a week, or as long as three weeks. People who are infected can travel a great distance before they begin to shed the virus. Initial symptoms are similar to those caused by malaria and influenza, confounding a proper diagnosis.
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How the world let Ebola spread

This is the problem. Say, you get into a taxi in Liberia but never even saw or met a person with Ebola. But, someone had tried to get to the hospital and the driver hasn't cleaned the back seat from sweat or spittle or urine from them and you become infected. So, you board a plane never having ever met or seen an Ebola patient. But, you are infected by the back seat of a taxi just like the NBC cameraman, Ashoka. Then since you never saw or met anyone who had Ebola you have no clue you have been exposed. Let's say you are traveling around the world to the U.S. , India and China. You hop on the plane and fly to the U.S.  you spend a week there. Then you fly to India and spend a week there. Then you fly to China and spend a week there and notice you have a fever while you are in Beijing. So, you go to a hospital and are diagnosed with Ebola. How many people are going to need to be quarantined in the U.S. , India and China as a direct result? And since you are feeling sick in Beijing you can't deal with those you exposed in the U.S. , and India so you just lay there because you can't talk anymore. What happens to all the exposed people who don't know they were exposed?