WHO effort to eradicate polio in danger

WASHINGTON -- Global efforts to eradicate polio are in danger of failing because of problems in stopping transmission in India and Nigeria and of concern among donors that the job may take much longer than anticipated, international health specialists said yesterday.

The World Health Organization's technical advisory panel on polio eradication discussed the consequences of failure yesterday at the start of a two-day meeting in Geneva, officials said. But they decided there was no option but to push ahead toward eradication, Bruce Aylward , WHO's head of the polio-eradication program, said in a telephone interview last night.

``This is the venture capital of public health," he said of the program, which started 19 years ago and has cost $4 billion so far. ``If it succeeds, it's massive. If it fails, there will substantial indirect benefits, but it will be a great loss."

The last four remaining countries in which the disease is still spread -- Pakistan and Afghanistan, in addition to Nigeria and India -- ``are tough places," Aylward said. ``We have a political challenge in Nigeria, a technical challenge in India, and in Afghanistan and Pakistan we are up against the war on terrorism. The question now is, `How do you do it in those settings?' "

But for an increasing number of global health specialists the question is whether the goal of eradication is the right one.

``There is fatigue from donors of being promised over and over again that we are going to achieve eradication by a certain date, and then not achieving it," said Scott Barrett , director of the international policy program at Johns Hopkins University's School of Advanced International Studies. ``Getting close is a remarkable achievement , but it's not the same as eradication. And there are dangers of being close, because . . . if vaccination drops off and polio comes back, then people would be exposed to the virus."

In addition, many wealthy countries are likely to continue vaccinating children for polio even if the disease is eradicated, in part because of post-Sept. 11 fears of a bioterrorism attack or the chance of unintentional leak from thousands of laboratories that now have frozen samples of the polio virus, Barrett and others said.

If rich countries wouldn't save money from global eradication, they would have less financial incentive to back the effort. The United States now spends hundreds of millions of dollars annually on polio vaccinations, even though transmission of the virus was halted 15 years ago in the Americas.

Quietly, those in public health circles have been debating the wisdom of the goal of polio eradication for more than a decade, raising scientific, economic, and logistical concerns. In the past several months, that debate has started to go public. In May, in an article in the journal Science, three international health specialists argued against the current strategy and instead supported ``control" of the disease, saying that other serious health needs in sub-Saharan Africa were worthy of more attention.

The world has eradicated only one other disease -- smallpox in 1979 -- which is widely seen as an extraordinary health and economic accomplishment. The decade-long smallpox effort had one large advantage over the polio initiative: Those infected with smallpox were highly visible, with marks over their bodies, while the vast majority of those infected with polio show no outward signs of having the disease and yet can still transmit it. Transmission is through contaminated feces, often in waterways; children with unwashed hands can easily become infected.

Another complication in eradication is that the oral polio vaccine can transmit the virus itself, if in minuscule numbers. Some scientists, including D.A. Henderson , one of the leaders in global smallpox eradication, have long argued that organizers overseeing the endgame of polio would need to shift from the oral vaccine to the injectible polio vaccine used in wealthy countries in order to fully stop transmission.

The antipolio partners -- WHO, UNICEF, Rotary International, and the Centers for Disease Control and Prevention -- have missed eradication goals for 2000 and 2005, and last year announced a 2007 target.

``This is a challenge in terms of how long do you keep at it, and at what point does the cost of continuing exceed the benefit of the end point?" said Nils Daulaire , president and CEO of the Global Health Council, the world's largest alliance of health organizations. ``There isn't any correct answer to that."

Aylward and others now are trying to get leaders in Nigeria, India, Pakistan, and Afghanistan more focused on the need for much better immunization campaigns. One outside pressure point is Saudi Arabia's decision recently to require that all Nigerians present proof of polio vaccination before traveling for the Haj pilgrimage or for any other reason to their country.

As of Oct. 4, Nigeria has registered 847 cases of polio, more than any country since India recorded 1,600 cases in 2002. India, which had just 30 cases last year, has recorded 352 so far this year. Afghanistan has 28 cases and Pakistan 23 so far this year, both eclipsing last year's numbers.

Several health specialists said members of the WHO panel should set a more realistic goal for polio eradication and release more specific strategies for the final push.

``You don't want to declare failure even when things are failing," said Gerald T. Keusch , associate dean for global health at Boston University's School of Public Health. ``You need to regroup and modify the strategy."

John Donnelly can be reached at donnelly@globe.com