A new campaign has been announced to eradicate polio. The six-year plan costing $5.5 billion was unveiled Thursday at the Global Vaccine Summit in Abu Dhabi.

The Global Polio Initiative says the plan is the first that aims to eradicate all types of polio ¨C the wild poliovirus and vaccine derived cases. Health officials say on rare occasions, the live, but weakened poliovirus in the oral vaccine may genetically alter in the immunized person¡¯s gut triggering the disease.

If all the funding comes through, more than one billion children could be vaccinated. UNICEF, the U.N. children¡¯s fund, describes ending polio as a historic feat for humanity.

¡°This is really the beginning of the end. We¡¯re tantalizingly close to eradicating polio and really making history. So it¡¯s an extraordinary opportunity,¡± said UNICEF spokesperson Sarah Crowe.

"Never before have there been fewer cases in fewer places,¡± she said.

There were 223 cases reported last year and just 19 so far this year.

¡°We must seize this opportunity because if we don¡¯t make history ¨C and we last made history, the grand we, was smallpox. The last time a disease was eradicated,¡± she said.

That was 1979. But the world was close to polio eradication before. It was nearly achieved in 2005, but immunization faltered in some countries, like Nigeria. So what¡¯s different now?

Crowed said, ¡°Because we¡¯ve never been as close. We¡¯re down now to three endemic countries in the world ¨C Afghanistan, Pakistan and Nigeria. And in those cases there are really just a handful of children who have been affected by polio this year. So we¡¯ve never seen that kind of a drop-off in history.¡±

At the Global Vaccine Summit, leaders and philanthropists have pledged nearly three-quarters of the funding. $1.5 billion in pledges is still needed.

The polio eradication plan is seen as part of an overall effort to provide vaccines to children around the world.