Dr. Margaret Chan, director-general of the World Health Organization, said despite the dramatic drop in polio cases in the last year, the threat of continued transmission due to immunization gaps drove the Global Polio Eradication Initiative to begin an emergency action plan.
The plan aims to boost vaccination coverage in the three remaining polio endemic countries -- Nigeria, Pakistan and Afghanistan -- to levels needed to stop polio transmission.
In addition, health ministers meeting at the World Health Assembly this week in Switzerland, are considering a resolution to declare "the completion of polio eradication to be a programmatic emergency for global public health."
India, long-regarded as the nation facing the greatest challenges to polio eradication, was removed from the list of polio-endemic countries in February.
But cases continue to occur in Nigeria, Pakistan, Afghanistan and Chad. Outbreaks in recent years in China and West Africa due to importations from Pakistan and Nigeria highlight the continued threat of resurgence.
"Polio eradication is at a tipping point between success and failure," Chan said in a statement. "We are in emergency mode to tip it towards success -- working faster and better, focusing on the areas where children are most vulnerable."
By some estimates, failure to eradicate polio could lead within a decade to as many as 200,000 paralyzed children a year worldwide, Chan added.