analysisBy Dan Pawson
Hundreds of scientists, doctors and other experts from around the world launched the Scientific Declaration on Polio Eradication last week, declaring that an end to the paralysing disease is achievable, and endorsing a comprehensive new strategy to secure a lasting polio-free world by 2018. The declaration's launch coincides with the 58th anniversary of the announcement of Jonas Salk's revolutionary vaccine.
The polio endgame
The more than 400 signatories to the declaration urged governments, international organisations and civil society to do their part to seize the historic opportunity to end polio and protect the world's most vulnerable children and future generations from this debilitating but preventable disease.
The declaration calls for full funding and implementation of the Polio Eradication and Endgame Strategic Plan 2013-2018, developed by the Global Polio Eradication Initiative (GPEI). With polio cases at an all-time low and the disease remaining endemic in just three countries, the GPEI estimates that ending the disease entirely by 2018 can be achieved for a cost of approximately $5.5 billion.
"Eradicating polio is no longer a question of technical or scientific feasibility.
Rather, getting the most effective vaccines to children at risk requires stronger political and societal commitment", said David Heymann, head and senior fellow at the Chatham House Centre on Global Health Security and a signatory of the declaration. "Eliminating the last 1% of polio cases is an immense challenge, as is the eradication endgame after that. But by working together we can make history and leave the legacy of a polio-free world for future generations."
The declaration notes that polio vaccines have already protected hundreds of millions of children from the disease and eliminated one of the three types of wild polio virus, proving that eradication is scientifically feasible.
It calls on the international community to meet the goals in the GPEI plan for delivering polio vaccines to more children at risk, particularly in Afghanistan, Nigeria and Pakistan, where polio remains endemic and emergency action plans launched over the past year have resulted in significant improvements in vaccine coverage.
"Securing a lasting polio-free world goes hand in hand with strengthening routine immunisation. We need all countries to prioritise investments in routine immunisation," said Zulfiqar Bhutta, founding director of the Center of Excellence in Women and Child Health at Aga Khan University. Bhutta, one of the declaration's leaders, is a member of the Strategic Advisory Group of Experts (SAGE) on Immunisation, a technical advisory body to the GPEI.
The declaration emphasises that achieving polio eradication requires efforts interrelated with strengthening routine immunisation, a new focus of the GPEI plan.
As the last cases of polio are contained, high levels of routine immunisation will be critical. At the same time, resources and learning from polio eradication efforts can be used to strengthen coverage of other life-saving vaccines, including for children who have never been reached with any health interventions before.
The scientists and experts signing the declaration called on the international community to take steps outlined in the GPEI plan to address challenges that have posed obstacles to polio eradication in the past, including improving immunisation campaign quality to reach missed children and eliminating rare polio cases originated by the oral polio vaccine.
While previous polio efforts have sought to interrupt wild virus transmission and then address the vaccine-derived virus, the new GPEI plan addresses both simultaneously with a timetable to phase out use of oral polio vaccines and introduce inactivated polio vaccines.
The declaration urges vaccine manufacturers to provide an affordable supply of the different vaccines required for eradication, and calls on scientists to continue researching new and better tools.
"As long as it exists anywhere in the world, polio threatens children everywhere", said Helen Rees, executive director of the Wits Reproductive Health and HIV Institute at the University of the Witwatersrand in South Africa, who signed the declaration and chairs SAGE.
"By pursuing in parallel all of the steps needed to reach eradication, including the switch to inactivated vaccines, countries have a complete path to eliminate polio's threat."
In November 2012, SAGE recommended the introduction of at least one dose of inactivated polio vaccine into all routine immunisation programmes prior to the phase-out of oral polio vaccines.
In light of recent attacks on health workers in some endemic countries, the declaration also stresses the need to protect polio vaccination teams as they do their work. The GPEI plan includes a series of risk-mitigation strategies for insecure areas, including deepening engagement with community and religious leaders.
The scientists and experts signing the declaration hail from 80 countries and include Nobel laureates, vaccine and infectious disease experts, public health school deans, paediatricians and other health authorities.
"We have the tools we need and a time-limited opening to defeat polio. The GPEI plan is the comprehensive roadmap that, if followed, will get us there", said Walter Orenstein, professor and associate director of the Emory Vaccine Center at Emory University and former director of the US Centres for Disease Control and Prevention's National Immunisation Programme.
Orenstein is one of the scientists spearheading the declaration and among the signatories who were on the frontlines of ending smallpox, the only human disease to be successfully eradicated.
The declaration notes that the world has a unique window of opportunity to eradicate polio. Only 223 new cases due to wild poliovirus were recorded in 2012, an historic low and a more than 99% decrease from the estimated 350,000 cases in 1988.
Just 16 new cases have been reported so far in 2013 (as of 9 April). India, long-regarded as the most difficult place to eliminate polio, has not recorded a case in more than two years.
Dan Pawson works for Global Health Strategies.