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Fact Release No 114
Revised September 2000)

POLIOMYELITIS

Poliomyelitis and its Symptoms: Poliomyelitis (polio) is a highly infectious disease caused by a virus. It invades the nervous system and can cause total paralysis in a matter of hours. The virus enters the body through the mouth and multiplies in the intestine. Initial symptoms are fever, fatigue, headache, vomiting, stiffness in the neck and pain in the limbs. One in 200 infections leads to irreversible paralysis (usually in the legs). Between five and ten per cent of people infected with polio die when their breathing muscles are paralyzed.

Persons at risk of polio: Polio mainly affects children under three years of age.

Prevention of polio: As there is no cure for polio, the best treatment is preventive. A few drops of powerful vaccine will protect a child for life.

Polio caseload: At the end of 1999 there were 7 094 reported polio cases. Recognizing that not every case is reported, the World Health Organization (WHO) estimates that no more than 20 000 cases occurred in 1999. Tens of thousands more children are infected with the virus; while they do not suffer paralysis, they can infect other children.

The Global Polio Eradication Initiative

Launch: In 1988, the 41^st World Health Assembly, consisting then of delegates from 166 Member States, launched a global initiative to eradicate polio by the end of the year 2000. This followed the successful eradication of smallpox in 1979 and progress during the 1980s towards elimination of the poliovirus in the Americas, as well as Rotary International's commitment to raise funds for polio eradication.

Progress: In 12 years since the Global Polio Eradication Initiative was launched, the number of cases has fallen by more than 95 per cent from an estimated 350 000 cases; the number of polio infected countries has fallen from 125 to 30 at the end of 1999. In 1994, the Americas were certified polio-free. Polio is gone form the WHO Western Pacific region, which includes China, and the WHO Europearegion. Widely endemic on five continents in 1988, polio is now concentrated only in parts of sub-Saharan Africa and the Indian sub-continent.

Strategies: The eradication of polio requires a programme of work ranging from massive immunization activities to aggressive laboratory containment of poliovirus stocks. In order to realize the full humanitarian and economic benefits of polio eradication, the programme also extends to international consensus building of future immunization policy.

There are five main categories of activities necessary to realize polio's eradication, the global certification target of 2005, and eventual cessation of polio immunization.

1. Conduct effective and high-quality national immunization days (NIDs) and mop-up campaigns to interrupt wild poliovirus transmission
2. Develop and sustain certification-standard surveillance and laboratory systems that can rapidly identify polio-infected areas
3. Ensure laboratory containment of wild poliovirus stocks
4. Develop a consensus strategy to stop polio immunization after certification or eradication
5. Use polio eradication to strengthen and expand routine immunization services

Immunization and high quality surveillance need to continue for a number of years after the last polio case has been detected before a region can be certified polio-free. Laboratory stocks must be contained before the world can be certified polio-free.

The target date for certification of the world as polio-free is 2005.

Coalition: The Global Polio Eradication Initiative is spearheaded by WHO, Rotary International, the Centers for Disease Control and Prevention (CDC) and the United Nations Children's Fund (UNICEF).

This coalition also includes national governments; private foundations (e.g. United Nations Foundation, Bill & Melinda Gates Foundation); development banks (e.g. World Bank); donor governments (e.g. Australia, Belgium, Canada, Denmark, Finland, Germany, Italy, Japan, the Netherlands, Portugal, United Kingdom and United States of America); humanitarian organizations (e.g. the International Red Cross and Red Crescent movement) and corporate partners (e.g. Aventis Pasteur, De Beers). Volunteers in developing countries also play a key role; ten million have participated in mass immunization campaigns.

Countries at Risk of Polio

So long as a single child remains infected with poliovirus, children in all countries are at risk of contracting the disease. The poliovirus can be easily reimported into a country and spread rapidly.

At the end of 1999, there were 30 remaining polio-infected countries. Twenty three had confirmed wild poliovirus: Afghanistan, Angola, Bangladesh, Benin, Central African Republic, Cameroon, Chad, Cote d'lvoire, DR Congo, Egypt, Ghana, Guinea, India, Iraq, Liberia, Niger, Nigeria, Pakistan, Sudan, Mali, Nepal, Sierra Leone and Togo. Seven were likely to have wild virus circulating but surveillance was not necessarily detecting it: Burkina Faso, Congo, DPR Korea, Eritrea, Ethiopia, Guinea-Bissau, Somalia. In addition, three countries had importations: China, Iran and Myanmar.

There 10 ten highest priority countries, and they fall into two categories.

• 'Poliovirus reservoirs' where transmission is particularly intense. These countries are characterized by large populations with low routine immunization coverage and poor sanitation. They are Bangladesh, Ethiopia, India, Nigeria and Pakistan.
• Countries affected by conflict, where implementation of vaccination and surveillance activities is particularly challenging. They are Afghanistan, Angola, the Democratic Republic of the Congo, Somalia and Sudan.

Challenges Faced in Polio Eradication

Polio eradication faces three main challenges:

Access: Securing access to all children, especially those in conflict-affected countries, is crucial. The success in establishing access, cease-fires and "Days of Tranquillity" for countries such as Afghanistan and the Democratic Republic of the Congo demonstrates the feasibility of working successfully in conflict-affected areas. These efforts must be expanded, drawing upon the strengths of the UN Secretary-General's office, many UN agencies, the International Red Cross and Red Crescent movement, and other new and existing partners.

Funding: Necessary financial resources must be secured to purchase OPV, plan and implement national immunization days and mop-up campaigns, and cover surveillance and laboratory costs. The total external financial support needed through to 2005 - the target date for certification - is US $1 billion. The financial shortfall is US $450 million. A failure to interrupt transmission within the next 24 months will increase the cost of the programme by an estimated US $200 million.

Political Commitment: Sustaining political commitment from the highest levels of government is particularly challenging in the face of a disappearing disease. In polio-endemic countries, personal monitoring by the head of state of the progress towards eradication is key to improving the quality of activities. In polio-free countries, political commitment is needed for sustaining certification-standard surveillance and achieving laboratory containment of poliovirus.

In addition, priority reservoir countries require a special effort, including extra national immunization days (NIDs) and house-to-house mop-up campaigns in large geographic areas. Better surveillance is needed to find the last cases in every country and evaluate the status for certification.

Once polio is eradicated, the laboratories of the world will be the only remaining source of the virus. As an increasing number of countries become polio-free, the virus needs to be safely and securely stored in laboratories to ensure no inadvertent release occurs after eradication.

Impact of the Global Polio Eradication Initiative

• Since the global initiative began in 1988, three million people in the developing world, who would have been paralyzed, are walking because they have been immunized against polio. Nearly two billion children worldwide have been immunized during national immunization days in the last five years, including 147 million children in a single day in India.
• Tens of thousands of public health workers have been trained to investigate cases of paralysis and manage immunization programmes.
• On average, one out of 250 people in a country are involved in polio immunization campaigns. Tens of millions of volunteers have been trained to deliver oral polio vaccine and vitamin A.
• In 1999, over 50 countries gave vitamin A during polio national immunization days, preventing the deaths of an estimated 250,000 children.
• Cold chain, transport and communications systems for immunization have been strengthened.
• A polio laboratory network of 148 polio laboratories has been established.

Future Benefits of Polio Eradication

• The savings of polio eradication, once immunization stops, are estimated to be US$ 1.5 billion per year - funds that can be used to address other public health priorities.
• In many countries polio eradication is expanding the capacity to tackle other diseases by building effective disease reporting and surveillance systems, training epidemiologists and establishing a global laboratory network.
• No child, regardless of race, sex, ethnicity, economic status or religious belief, need ever fear and suffer from this crippling disease.