Fear and suspicion have prevented thousands of children like Fahad from being protected against the infectious and incurable disease. Now more than ever, it's time that stopped, Gates says.

Rumors that polio immunization campaigns are "Western plots to sterilize Muslims" or that the vaccine is "George Bush's urine" underline the need to take politics out of the fight to eradicate polio, he says.

If Gates, the most influential of global health advocates, gets his wish - and in an interview he's pretty sure he will - the world won't stop at the 99 percent reduction in cases so far, but will rid itself of polio completely by 2018.

Yet evidence from Pakistan and Afghanistan, two of only three countries where polio is still endemic, suggests a battle lies ahead to overcome Taliban opposition, vaccine refusals, security and funding gaps to beat out that last one percent.

"We are working hard to depoliticize the whole thing," said Gates, whose $35 billion Gates Foundation is spearheading international efforts to eradicate the disease.

He noted what he called "episodes of lack of communication" between those who want to rid the world of polio and some Taliban leaders, but was optimistic that working with new donors and using local knowledge would secure eventual success. He is eager to involve more donors from Muslim countries.

"In no way should this campaign be associated with just the West," he said. "This is the whole world working together to eradicate a disease."

PARALYSED FOR LIFE

Polio attacks the central nervous system and can cause permanent paralysis within hours of infection. Two-year-old Fahad is one of 35 children struck down with it in Pakistan so far this year.

"Fahd's left leg went completely limp, and slowly, in a day or so, his right leg was gone too," his father says.

There is no cure for polio, but it can be prevented. A polio vaccine given in several doses can protect a child for life.

The most recent case in Pakistan was recorded on August 30, and because polio spreads from person to person, the World Health Organization says as long as any child remains infected, children everywhere are at risk.

Afghanistan and Nigeria have recorded 17 and 88 cases so far this year respectively, while Chad, a non-endemic country which borders Nigeria, has had five.

Immunizing the last children on earth is an expensive, business - not because the vaccine is costly (most are made by generic manufacturers and cost between 12 and 14 U.S. cents a dose), but because reaching people displaced by war and poverty requires vast operational logistics, time and human resources.

Gates and experts at the Global Polio Eradication Initiative insist the $2 billion a year needed now will be well worth it. They say if the campaign succeeds, the world would not only declare its second eradicated disease - smallpox was wiped out in 1979 - it would also be billions of dollars richer.

A 2010 study found that if polio transmission were to be stopped by 2015 the net benefit from reduced treatment costs and productivity gains would be $40 billion to $50 billion by 2035.

Yet getting the pink drops of protective vaccine into every child - over 90 percent coverage is needed to succeed in wiping out this highly infectious disease - is complex.

Immunization campaigns have been disrupted by fighting along the Afghan-Pakistan border where villages are home to many of the children missed so far.

And fear is being spread by local Taliban leaders such as Maulana Fazlullah, nicknamed Mullah Radio for his broadcasts from the Swat Valley northwest of Islamabad, who denounces polio vaccinations as Western plots and threatens those who argue.

Senior Taliban commanders, Maulvi Raza Shah and Sirajuddin Ahmad, say they oppose polio vaccines because they don't know what is in them and believe they are part of a plot by the West to sterilise Muslims.

"Every drug has a known formula but polio vaccine has no formula. And then the United States and its allies are giving us this vaccine free of cost when they don't even give free water to their own people," said Raza Shah.

Accusations that immunization campaigns are cover for spies were given credence when it emerged that the United States had used a Pakistani vaccination team to gather intelligence about Osama bin Laden.

RISKS AND CONSEQUENCES

At his temporary home in Jalozai, a sea of refugee tents where the family now lives with others displaced by violence, Fahad's father Mohammed Usman talks of the tragic consequences of such cultural and religious clashes. He says it breaks his heart every time he sees his son struggle to stand.

"It's very painful for me to hold him, to know that he will not be able to walk. Every time his mother looks at him she has pain in her eyes," he says.

It was fighting, not fear, that prevented Fahad from being immunized. Teams could not reach his home near the border with Afghanistan. "We have a lot of pockets we have not reached for years," said Elias Durry, who coordinates the WHO's polio eradication drive in Pakistan.

Health workers fear that as families like the Usmans flee into safer, more populated areas, they may bring the disease with them, reinfecting areas that were previously polio-free. Last year, a strain from Pakistan was found to have spread northeast and caused the first outbreak in China since 1999.

Experts estimate that in the three endemic countries, plus other high-risk neighbors such as Chad, Angola and the Democratic Republic of Congo, there are 2.7 million children who have never received even a single dose of polio vaccine.

VACCINES REFUSED

Mohammed Usman says that when he learned his son had been paralyzed for life, he knew children had to be vaccinated whatever the risks. He braved fighting and the wrath of religious leaders to travel back to his village.

"I didn't want any other children to suffer, so I took a batch of vaccines to my village and gave them to over 50 children," he said.

Even in Peshawar, capital of Pakistan's northwest province, families often refuse vaccinations.

"They send these teams to every house. They want to know what we are up to, what we are thinking. It is all part of their plan to watch over us," said 45-year-old Nurdad Khan, who runs a clothes shop in Peshawar.

"The West wants to control our population and it's doing that through these vaccines that sterilise our children".

With tales like these, it's easy to see why in a February 2012 report, an independent monitoring board which scrutinizes the campaign to end polio, concluded that Pakistan represents one of the gravest risks to global eradication.

Yet it's also easy to lose sight of the bigger picture - one of progress against a disease that until the 1950s crippled thousands every year in wealthy nations, and tens of thousands more in poor ones. In under three decades, the number of polio cases worldwide has fallen by 99 percent from 350,000 cases in 1985 to 650 cases in 2011. So far in 2012 there have been 145.

One of the biggest victories has been India - expected by many to be the last place to beat polio due to its high levels of poverty and cramped urban populations. In January, the country marked a year free of the disease.

ISLAMIC INVESTMENT IN A POLIO-FREE WORLD

Experts say if the eradication effort fails and polio rebounds, the virus could cause up to 10 million cases in the next 40 years. The human and economic costs of that would go way beyond the $9 billion invested so far in trying to wipe it out.

At this point, though, there is an almost $1 billion shortfall in funding for the fight against polio, according to the independent monitoring board's report.

At the United Nations General Assembly in New York this week, Gates held talks with the presidents of Pakistan, Nigeria and Afghanistan, as well as senior government officials from Australia, the United States, Britain, Japan and Canada.

At the same meeting, the president of the Islamic Development Bank announced a loan agreement for $227 million to cover Pakistan's polio eradication costs. The bank also gave a $3 million dollar grant to Afghanistan.

Gates describes this meeting of so many key players in the bid to end polio as a "great evolution".

"We've got the Islamic Development Bank coming in, we've got ongoing commitment from Abu Dhabi, and we'll have people from both those donors going out to Pakistan to talk about how committed they are and how important this is," he said.

This high level support, he says, will be combined with detailed house by house or tent by tent plans which document which families are refusing the vaccine, why they are, and whether follow-up with a religious, social or medical official is likely to be most successful in changing their minds.

"Getting people to be comfortable with giving medicines to young children has always required really good social marketing, good outreach and good followup," said Gates. "Every piece you tighten up moves you closer towards getting the 90 percent of the kids to have the drops. And once you achieve that, you can succeed."

(Writing by Kate Kelland, additional reporting by Jibran Ahmad and Rebecca Conway in PESHAWAR, Shinwad Ibrahim in KHYBER, editing by Michael Georgy and Janet McBride)

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