Introduction

For centuries, some of the most dreaded words parents could hear from a child were, “I can’t move my legs.” Their child’s paralysis signaled polio, an infectious disease that has caused death, disability, and economic hardship throughout the world for centuries. Today, we are on the verge of polio eradication - a landmark conquest in the ongoing public health battle against disease epidemics. Not since the 1970s, with the successful eradication of smallpox, has the world undertaken a program of this magnitude.