| 1 | Why is it so important to end polio? | |
| 2 | But even India's urban environments have not seen an eradication of polio. | |
| 3 | Smallpox had a number of characteristics that made it easier to eradicate than polio. | |
| 4 | For example, because of donors' generosity, we are on the threshold of ending polio once and for all. | |
| 5 | We need to bring the cases down to zero, maintain careful surveillance to ensure the virus is truly gone, and keep defenses up with polio vaccines until we' ve confirmed success. |