BRUSSELS, Belgium — It's the classic airport scene: a man hugs his wife and two daughters at arrivals. But in this case, the traveler had just stepped off a plane from the Ebola-stricken Liberian capital of Monrovia —meaning that some might shy away from such embraces. "I've been screened before getting on the plane," he pointed out before heading for the exit.

The twice-weekly flight from Monrovia to Brussels is now the only air link from the city to the European continent — and is the route most Americans would likely travel on their way home. Thomas Eric Duncan, who died in a Dallas hospital last week, traveled to the U.S. from Liberia via Brussels.