WHO News

Polio eradication — the last and toughest 1%

Polio is clearly on its last legs. Figures released in mid-April by officials of the WHO-led global polio eradication initiative show an over 99% drop in estimated cases — from 350 000 in 1988, when the initiative was launched, to less than 3500 last year.

Trouble is, dealing with that residual 1% will be the initiative’s toughest task in its 13-year history. And it will be costly. The initiative, which is a coalition of international and national public- and private-sector entities, aims to stop polio transmission worldwide within the next 24 months. Then, by 2005, if no new cases have turned up, a global commission should be able to certify the world polio-free. Implementing that five-year plan will cost US$ 1 billion — 44% for operational expenses, such as transport, social mobilization and other logistic requirements for mass vaccination campaigns, 38% for the vaccine, 11% for disease surveillance and 7% for management, meetings, and the like.

The reason for the high cost is that of the 20 countries where wild polio is still endemic, 10 present formidable obstacles: large populations providing the virus with vast human reservoirs in which to circulate intensively and from which to spread to neighbouring countries (this is the case for Bangladesh, Ethiopia, India, Nigeria and Pakistan) or the presence of military conflict (Afghanistan, Angola, Somalia, and Sudan) or both (the Democratic Republic of the Congo). In addition, all are poor, with fragile or non-existent health infrastructures.

So far, of the needed US$ 1 billion, donors have promised US$ 600 million. Finding the rest is not going to be easy. Eradication initiative officials are concerned that the slew of new global health funds being set up or proposed — for AIDS, malaria, tuberculosis, children’s vaccines, and other worthy causes — is creating unprecedented demands on donors. Even without this new competition for resources, fundraising for polio faces an uphill struggle. ‘‘It’s an unfortunate paradox,’’ says Dr Bruce Aylward, who heads the team running the initiative. ‘‘The more successful eradication efforts are, the less visible polio becomes and the harder it is to generate the needed resources to finish the job.’’

Clearly the eradication initiative has been a success. In 1988, polio was present in 125 countries vs at most 20 countries at the beginning of this year. Over this period, an estimated 3 million people would have contracted polio had it not been for the initiative. This translates into an average cost of US$ 500 per case prevented.

But preventing each polio case is getting more expensive, as the virus retreats into increasingly inaccessible redoubts. Over the next five years, assuming that eradication activities will maintain their momentum, at most 10 000 cases would occur worldwide, eradication officials estimate. That means the cost of preventing each case will probably be about US$ 100 000.

But as Aylward points out, ‘‘We’re not just talking about preventing cases. We’re talking about wiping out an entire disabling disease forever — a disease that every year has been needlessly siphoning off from the world economy about $1.5 billion in vaccination and treatment costs.’’

Eradication officials are cautiously optimistic that donors and the initiative’s partners will come up with the US$ 400 million still needed. But will it come quickly enough to avoid a second postponement of the target eradication date, originally set for 2000? They hope so, as every year’s delay adds US$ 100 million to the total bill.

John Maurice, Bulletin