Globalization has made international disease transmission easier, but it is unlikely to lead to large-scale global propagation in this case. For Ebola, the barriers to global spread are high. Highly infectious people are desperately sick; they will not be boarding airplanes. Travelers entering this stage after reaching their destinations will be identified and isolated by properly functioning health systems.

Nigeria provides an edifying example. The collapse of Liberian-American Patrick Sawyer in Lagos’s busy international airport on July 20 was the nightmare scenario—Ebola unleashed in a crowded venue, in a teeming megacity of the developing world. But rapid, well-coordinated action on the part of the Nigerian government averted disaster, and that West African nation’s incipient outbreak has been contained, despite a health system below developed-world standards.

Misjudgments are possible, as when Ebola patient Thomas Eric Duncan was turned away from a Dallas hospital, and subsequently died on Oct. 8. Protective protocols can be insufficient or break down, as was the case for health-care workers who cared for Duncan and for a nurse’s assistant who contracted Ebola in Spain. But as the threat of Ebola importation becomes more widely understood, health-care professionals and facilities are better prepared with each passing day. What the public should understand is this: Vigilance and decisive action can halt Ebola’s spread even under adverse circumstances.