If the current global campaign to eradicate polio succeeds, the virus will no longer be in circulation in a year's time. But this will also be the beginning of a highly risky final phase in eliminating the disease for good.
In this article, Leslie Roberts lays out the challenges that will face the campaign team once the disease is no longer being transmitted. The biggest threat is that the live virus used in the vaccine could itself create a pandemic. This will make it necessary both to collect virus stocks from laboratories and factories around the world, and stockpile enough of it to combat any future outbreaks.
The scale of these operations is only one difficulty ahead. Close international cooperation and coordination of control efforts will also be required — and this, say some, will be difficult to achieve in many of the world's poor and war-torn countries.
Reference: Science 303, 1969 (2004)