The legacies of polio eradication
C. de Guerra MacedoI; B. MelgaardII
IFormerly Director, World Health Organization Regional Office for the Americas/Pan American Sanitary Bureau, Washington, DC, USA. Member of the Global Commission for the Certification of the Eradication of Poliomyelitis
IIDirector, Vaccines and Biologicals, World Health Organization, 1211 Geneva 27, Switzerland
Mum Chanty, a three-year-old Cambodian girl, was diagnosed with polio in March 1997. She will probably never walk again without assistance. Mum is a poignant reminder of both the devastating effects of the disease and the success of current efforts to eradicate it. She is the last person to be diagnosed with polio in the Pacific Rim countries. Next year, these countries will be certified free of polio, leaving only two areas in the world, South Asia and sub-Saharan Africa, with poliovirus still circulating. The Americas were the first region to be certified polio-free in 1994, proving the technical feasibility of polio eradication.
It is clear that the polio virus is being herded into its very last hideouts and, even in countries riven by conflict or with only rudimentary health services, the eradication drive is on the way to a successful conclusion (1). In August 1999, the Democratic Republic of the Congo vaccinated over 80% of children under five in its first nationwide immunization campaign, overcoming the political and logistic obstacles of war in a country the size of western Europe. Worldwide, in the 11 years since the World Health Assembly passed a resolution to eradicate polio, estimated numbers of paralytic polio cases have fallen from over 400 000 to less than 20 000 a year.
Yet, not surprisingly, the huge effort and funds required to achieve eradication have raised fears in some quarters that equally essential routine health activities will be neglected.
These fears should not be ignored. While there is no evidence that there is any lasting damage, it is true that routine immunization often stops during National Immunization Days as health workers and resources are transferred to the intensive campaigns.
In a qualitative evaluation in six countries in the Americas which was mainly positive in its findings, strong negative effects were found related to the targeting strategy, and to a lesser degree to the involvement of leaders (2). Overall the negative effects were greatly outweighed by the benefits. Strong positive scores were seen in social mobilization, communication, management, and relations between communities and service providers; weaker positive scores were registered for community organization and interagency cooperation.
Another study in Nepal and the United Republic of Tanzania in June 1999 found the programmes high public focus had the potential to divert donor attention and resources, and distort established national policies and priorities for health development due to competing priorities (3).
But we believe, and the studies above have also shown, that any negative effects are surpassed by the tremendous legacies that the polio eradication initiative will leave.
A first legacy will be the removal of the suffering caused by this disease.
A second legacy will be the saving every year of the US$ 1.5 billion now being spent annually on the treatment and prevention of polio (4).
A third legacy for many developing countries will be a stronger infrastructure for routine immunization, disease surveillance, health management, and the delivery of other health interventions, including vitamin A supplementation. This is borne out by our experience in wiping out the disease in the Americas. A direct consequence of polio eradication in the region has been the establishment of measles surveillance systems and immunization.
A fourth legacy will be greater visibility of health services generally and immunization in particular. In Yemen for example, the public response to National Immunization Days has led to a tenfold increase in the national budget for the Expanded Programme on Immunization. For polio itself, that greater visibility is to a large degree the result of the mobilization of all strata of society, from political leaders to the general public: kings, presidents, prime ministers have launched polio immunization campaigns; charities have provided vast sums of money to fuel the eradication initiative; Rotary International will have contributed US$ 500 million by 2005; commercial companies have donated money and millions of doses of polio vaccine.
A fifth legacy stems from the way in which the polio initiative has prepared the ground for other disease control strategies, such as measles and malaria (5). These diseases differ in many respects from polio: they have different epidemiologies and therapeutic approaches. But they both require technically sound, well-organized, well-funded control programmes. The polio initiative has helped build consensus and confidence in public health in general and expand funding. As a vehicle for lasting health benefits, the Polio Eradication Initiative will be positioned at WHO as a platform for preventive health services (6).
We have no doubt that the eradication of polio will, as smallpox eradication did before it, revitalize disease prevention right across the public health spectrum. Nor have we any doubt that this collective human endeavour, that has harnessed the energies and resources of so many sectors of society, will take its rightful place as one of humanitys most significant achievements.
1. Tangermann R et al. Eradication of poliomyelitis in countries affected by conflict. Bulletin of the World Health Organization, 2000, 78: 330338.
2. The impact of the Expanded Programme on Immunization and the Polio Eradication Initiative on health systems in the Americas. Final report of the Taylor Commission. Washington, DC, Pan American Health Organization, 1995.
3. Mogedal S, Stenson B. Disease eradication: friend or foe to the health system? Synthesis report from field studies on the polio eradication initiative in Tanzania, Nepal and Lao PDR. Geneva, World Health Organization, 1999 (unpublished document of November 1999, available on request from the Department of Vaccines and Biologicals, World Health Organization, 1211 Geneva 27, Switzerland).
4. Bart KJ et al. Global eradication of poliomyelitis: benefitcost analysis. Bulletin of the World Health Organization, 1996, 74: 3546.
5. Aylward RB et al. Disease eradication as a public health strategy: a case study of poliomyelitis eradication. Bulletin of the World Health Organization, 2000, 78: 285297.
6. Goodman T et al. Polio as a platform: using national immunization days to deliver vitamin A supplements. Bulletin of the World Health Organization, 2000, 78: 305314.