The global campaign to wipe out polio is getting a $200 million donation from Rotary International and the Bill & Melinda Gates Foundation, at a time when some worry the effort will fail in the final stages.
Monday's announcement by both organizations came after nearly two decades of work against polio, an infectious disease that can paralyze and sometimes kill.
"This investment is precisely the catalyst we need as we intensify the push to finish polio," Dr. Margaret Chan, director-general of the World Health Organization, said in a statement.
Though polio incidence has been slashed by more than 99 percent worldwide since the eradication effort began in 1988, the virus remains entrenched in Afghanistan, India, Nigeria and Pakistan.
Two deadlines to eliminate polio have been missed: 2000 and 2005. More than $5 billion has been poured into the effort, and some experts worry that unless the job is finished soon, the world community's money and patience may run out.
"They're on a heroic task, but money is not the only problem," said Dr. Donald A. Henderson, who headed WHO's smallpox successful eradication campaign. "We've got to soldier on. We need more money. Look at all we've accomplished. But how do we get to the endpoint?"
Henderson and other experts worry that major obstacles to vaccinating children will be harder to overcome than filling a funding gap.
In countries like Pakistan, Afghanistan, Somalia and Congo, where there are armed conflicts and weak health services, it has been extremely difficult to reach the high vaccination levels needed to wipe out polio. And in India, the vaccine is less effective, due to poor sanitation and the fact that children are often infected with intestinal viruses.
Experts are also concerned about the use of the oral vaccine, which contains live polio virus. In rare instances, the virus can mutate into a dangerous form capable of causing the disease.
The donation from Rotary International and the Gates Foundation, to be paid over three years, will largely go to immunization campaigns, surveillance and public education.
"This amount of money can make quite a big difference," said Nicholas Grassly, of Imperial College, London, who advises WHO on polio issues. "We can build on the gains that have been made this year."
WHO reports significant progress against polio in India and Nigeria, where 85 percent of the world's polio cases occur. Last year at this time, Nigeria had 958 polio cases. This year, only 226 were reported.
Still, the $200 million falls short of the $650 million that WHO says will be needed by 2009. Eradicating polio will ultimately cost $1 billion more, said Dr. David Heymann, WHO's top polio official.