Coalition declares 'final push' to end polio

Jun 18, 2008 (CIDRAP News) – The international coalition of health agencies dedicated to ending polio yesterday declared a "final push" toward the long-delayed goal of eradicating the disease. But its members coupled the announcement with a plea for millions of dollars in donations to fill shortfalls, and with an admission that the 20-year-old campaign continues to face stubborn challenges.

Leaders of the organizations that make up the Global Polio Eradication Initiative (GPEI)—the World Health Organization (WHO), the US Centers for Disease Control and Prevention (CDC), UNICEF, and Rotary International—announced the effort and fundraising drive in Los Angeles at Rotary's annual convention. Members of Rotary International have been polio eradication's volunteer shock troops since the campaign was launched in 1988 and have donated about $700 million to the effort.

"The greatest danger we have now is the danger of stopping too soon," Dr. Robert Scott, chair of The Rotary Foundation, said at a press conference. "We have to keep after this virus and finally eradicate it."

Dr. Margaret Chan, the WHO director-general, said she is "committing the entire [WHO] to putting polio as our top operational priority," but declined to offer details of how staff or funds might be shifted to carry that out. She ruled out hiring additional personnel. "We have people who can be mobilized for a short time," she said.

Yesterday's event showcased the launch of a "$100 Million Challenge," an effort to raise matching funds for a 3-year $100 million challenge grant given to Rotary in November 2007 by the Bill and Melinda Gates Foundation. The challenge is aimed at Rotarians, but the organization is also seeking contributions from nonmembers.

"We cannot afford to not eradicate polio," Dr. Julie Gerberding, the director of the CDC, said at the press conference. "It's an economic imperative for us on a global basis. It's also a moral imperative."

Funding challenges
But in a sign of the challenges confronting the eradication campaign, the initiative will face a severe shortfall even if the fundraising drive succeeds. According to WHO figures, over the next 2 years the effort will need $490 million beyond what governments and private organizations have already given or committed.

Representatives of many of those governments will appear at July's G8 summit in Japan, as yesterday's speakers acknowledged. Previous G8 summits have included commitments to continue funding eradication.

"We just would like to encourage [the G8] to continue to support us to finish the job," Chan said during the press conference.

The known shortfall is in addition to the more than $5 billion—$1 billion over initial projections—given since 1985, when the eradication effort began informally in the Americas as a project of the Pan American Health Organization.

The gap between funds given and funds needed is one of many hurdles facing the long push toward eradication, which was supposed to have been achieved first in 2000 and then in 2005. Once the second deadline passed, the WHO ceased setting official targets, though its published documents project the campaign through the end of 2009.

Significant strides, but not complete success
When the campaign began in 1988, polio paralyzed about 350,000 children per year in 125 countries worldwide. For more than a decade, the effort went well; at its lowest, in 2001, global incidence dropped to 483 new cases of the disease.

But the initiative proved more costly—not only in funds, but in personnel needs and political will—than was forecast. Polio rebounded wherever attention lapsed, and it posed biological and cultural challenges that were never anticipated.

In India's Bihar and Uttar Pradesh states, for a complex set of reasons having to do with poor sanitation and chronic gastrointestinal diseases, polio has proved so stubborn that children remained vulnerable to it after many more doses of vaccine than the norm.

The WHO several years ago deployed a reformulated vaccine aimed at the most infectious and pathogenic form of polio, known as type 1, in hopes of shifting the balance. Uttar Pradesh remained free of type 1 for a year, but discovered an imported case from Bihar in May.

In Nigeria, polio vaccination became the subject of political and religious manipulation when clerics and local politicians seeking to upset a power-sharing agreement presented it as a Western plot against Muslim children. Vaccination essentially ceased in the country's northern provinces from mid-2003 into 2004.

Transmission has never been halted in four countries: Afghanistan and Pakistan as well as India and Nigeria. In addition, the virus spread from India and Nigeria to reinfect 27 countries where it had been eradicated, and it currently persists in nine: Angola, Benin, Chad, Niger, the Central African Republic, Ethiopia, the Democratic Republic of Congo, Sudan, and Nepal. As of Jun 10, there have been 558 new cases this year.

'Vaccine-derived' polio
The campaign has always been dogged by a rich-poor imbalance. Industrialized countries use a more expensive injectable killed-virus vaccine, but poor countries—and the eradication campaigns operating within them—use the much less expensive, live attenuated-virus vaccine.

That approach contains a known hazard. The attenuated virus multiplies in the gut and is shed by vaccinated children, a benefit that offers potential passive immunization to other children who pick up the virus. But the vaccine virus can also mutate in the gut into a virulent type that causes polio paralysis—and, when shed, can threaten anyone not yet protected by vaccine.

The risk of "vaccine-derived polio" was graphically demonstrated last autumn when the CDC disclosed vaccine-derived polio cases in 10 countries, including a 69-person outbreak in Nigeria that paralyzed unvaccinated children. And because some rare individuals can shed virus for years, that risk has always been a troublesome wild card in plans to stop vaccinating post-eradication.

International fatigue with the campaign's complexity and cost has led some scientists, including the leader of the WHO's successful effort to eradicate smallpox in the 1970s, to recommend abandoning eradication in pursuit of long-term control. In a news headline in May 2006, the journal Science asked: "Polio eradication: Is it time to give up?"

But others contend the effort must be pursued to the endgame. In a cost-benefit analysis published in The Lancet in April 2007, Kimberly Thompson and Radboud Tebbens of the Harvard School of Public Health argued that even an additional $3 billion in spending to achieve eradication would be less expensive in the long run than either the price of continued immunization for long-term control, or the human cost of paralysis if the disease escapes control.

See also:

Rotary International press release

Rotary fund-raising Web site

Polio case counts, Global Polio Eradication Initiative

CDC. Update on vaccine-derived polioviruses--worldwide, January 2006-August 2007. MMWR 2007 Sep; 56(38):996-1001 [Full text]

Arita I, Nakane M, Fenner F. Is polio eradication realistic? Science 2006 May 12;312(5775): 852-4 [Abstract]

Roberts L. Polio eradication: is it time to give up? Science 2006 May 12;312(5775):832-5 [Abstract]

Thompson KM, Tebbens RJD. Eradication versus control for poliomyelitis: an economic analysis. Lancet 2007 Apr 21;369(9570):1363-71 [Abstract]

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