(CNN) The estimated 22,000 attendees of the Rotary International Convention were quick to their feet Monday morning in Atlanta.
Inspiration for the many standing ovations came not only from the encouraging words of Atlanta Mayor Kasim Reed, professional wrestling star John Cena, Rotary President John Germ and famed Microsoft founder Bill Gates. It was also the sight of observers in wheelchairs lining the middle rows of the Georgia World Congress Center auditorium that moved the crowd to rise from their seats again and again.
The Rotarians, wearing glowing LED bracelets, came to Atlanta to commit once again to the elusive goal they first outlined in 1985: a world free of polio, the highly infectious disease that invades the nervous system and can cause total paralysis in a matter of hours. The disease can be prevented by a safe vaccine, which can protect a child for life when given multiple times.
"Your involvement started over 30 years ago, and since then, (you have) faced challenges that no one would have predicted," said Gates, who was speaking on behalf of the Bill & Melinda Gates Foundation. Though he praised the Rotarians' hard-won achievements, he also addressed the hard question on the minds of most attendees.
The original plan was to end polio by the year 2000, come and gone: Why is it taking so long?
When first deciding to rid the world of polio, Rotarians knew that it would have to be a team effort, explained Germ, whose fundraising efforts earned him White House honors in 2013.
"That's how the Global Polio Eradication Initiative came into being, as a tremendous partnership between Rotary, the World Health Organization, the US Centers for Disease Control and Prevention and UNICEF," Germ said. In 2007, he said, the initiative gained a fifth partner: the Bill & Melinda Gates Foundation.
Germ described the original "deal" proposed by the Gates Foundation: "If we could raise $100 million for polio, they'd match it.
"We surpassed it."
After the initial match, the Gates Foundation next pledged an additional $250 million in 2009 if Rotary could raise another $100 million. Once again, Rotary rose to the occasion.
Though money may be "very critical," Gates said, it's "only one piece of the story. This is harder than any of us expected."
To eradicate polio, he explained, all 7.5 billion people on the planet must be free of the disease.
"That includes places where there is war. That includes countries where public health systems are virtually nonexistent," Gates said. It means reaching children in the "most difficult places on Earth, not just once" but as many times as necessary to ensure that they are protected.
Persistence also includes innovation, new ideas and adapting to unforeseen circumstances, Gates said. He lauded the volunteers and health workers who sacrificed their lives in conflict areas of political, religious and social division to get children vaccinated.
"I'm thinking of people like Marie-Irène Richmond Ahoua, who lives in Ivory Coast," he said.
After a coup years ago, Ahoua, a member of the Rotary Club of Abidjan-Biétry and president of the Commission Nationale Polio Plus, appealed to the new military ruler, who canceled a national immunization day. She told the general, "children should not suffer because of conflict created by adults," Gates recounted. Days later, the general himself presided over a rescheduled immunization day.
In Pakistan, where distrust of health providers ran high, Gates said, Rotarians worked with Islamic scholars and other religious leaders to gain endorsement and encourage vaccination programs among their followers.
"These efforts have helped reduced polio in Pakistan from 306 cases in 2014 to just two cases so far this year," Gates said, praising Nigeria's religious leaders, including the Emir of Kano, who publicly drank an entire vial of vaccine to assure people that it was safe.
The Atlanta audience cheered as a snapshot of the Emir knocking back a vial loomed on the monitors behind Gates.
Another reason the polio eradication goal has not been met is down to the challenge of "knowing where the children are who need to be vaccinated," Gates said. Lack of a simple item we take for granted in the West -- detailed maps -- has stalled progress in the effort to find "the last vestiges of the virus."
"We need to know where it is hiding," Gates said, explaining that one innovative idea is finding paralyzed children and testing their feces to see whether polio caused their impairments.
The 200,000 yearly stool samples from paralyzed children test negative for polio "99.9% of the time," Gates said, yet the mere fraction of positive results tells health care providers where to focus their efforts to stop polio from spreading.
Similarly, researchers in high-risk areas analyze sewage system waste to identify whether polio exists in the environment before it paralyzes a single child -- an innovation that "will get us to the goal of eradication," Gates said. In Nigeria, Afghanistan and Pakistan, more than 125 environmental detection sites are in operation.
Though the world is not yet polio-free, great progress has been made.
In 1985, when eradication of polio became Rotary's top philanthropic goal, Germ said, the disease paralyzed more than 350,000 children in 125 countries where the disease was endemic, or common, every year.
Today, the partnership has immunized 2.5 billion children worldwide. More than 16 million people are walking today who otherwise would have been paralyzed by polio, according to Germ.
Gates said, "In 1994, the Americas were certified as polio-free. In 2000, the Western Pacific region was certified as polio-free. In 2002, Europe was certified as polio-free. In 2014, Southeast Asia including India was certified as polio-free. This year. we're down to a handful of cases in just three countries: Pakistan, Nigeria and Afghanistan."
Fewer than 40 cases were reported for all of 2016, Gates said, largely because over 10 billion doses of oral polio vaccine have been administered by an "army of global volunteers" and "thousands of health care workers" since 2000.
"Not only are you eradicating one of the worst diseases in history, you're also helping the poorest countries provide their citizens with better health and a better future," he said, explaining that the infrastructure developed throughout the world has helped nations confront other deadly diseases, such as Ebola, and will help with others, including yellow fever and malaria.
Yet, Gates explained, all the hard-won successes could easily be lost if polio is not eradicated.
"Even when we get to zero, we have to go three years without a new case," he said. "We don't have any other option, because if we fail, polio will return to countries where it has been eliminated."
Losing the battle could mean up to 200,000 new cases in the next decade.
An additional $1.5 billion in funding will be necessary to complete the job of ridding the world of polio, Germ said. The good news is that Canada, Japan, Germany, Australia, the European Union and the United Arab Emirates have all stepped up with new pledges, while the US continues as the largest government funder of global polio eradication. All told, an additional $1.2 billion in funding was pledged at Monday's event.
The polio eradication effort has been a "great reminder to people we can accomplish great things when we're bold, determined and when we work together," Gates said. "People are living longer lives, healthier lives. When we have ended polio, it will be another triumph for mankind."