In the early 20th century, polio was one of the most feared diseases in industrialized countries, paralysing thousands of children every year. Soon after the introduction of effective vaccines in the 1950s and 1960s however, polio was brought under control and practically eliminated as a public health problem in these countries.It took somewhat longer for polio to be recognized as a major problem in developing countries. Lameness surveys during the 1970s revealed that the disease was also prevalent in developing countries. As a result, during the 1970s routine immunization was introduced worldwide as part of national immunization programmes, helping to control the disease in many developing countries. In 1988, when the Global Polio Eradication Initiative began, polio paralysed more than 1000 children worldwide every day. Since then, 2.5 billion children have been immunized against polio thanks to the cooperation of more than 200 countries and 20 million volunteers, backed by an international investment of more than US$ 8 billion.Today, polio has been eliminated from most of the world and only four countries remain endemic. In 2009, fewer than 2000 cases were reported for the entire year. Use this interactive timeline to trace the history of polio from 1580 B.C. to the present.
An Egyptian stele portrays a priest with a withered leg, suggesting that polio has existed for thousands of years.
British physician Dr Michael Underwood attempts the first-known clinical description of polio, called “debility of the lower extremities”.
In Germany, Dr Jacob von Heine conducts the first systematic investigation of polio and develops the theory that the disease may be contagious.
The first significant outbreak of infantile paralysis – subsequently identified as polio – is documented in the United States of America.
Swedish paediatrician Dr Ivar Wickman categorizes the different clinical types of polio.
Austrian physicians Karl Landsteiner and Erwin Popper hypothesize that polio may be caused by a virus.
A polio epidemic in New York, USA, heightens concern on both sides of the Atlantic and accelerates research into how the disease is spread.
Sir Macfarlane Burnet and Dame Jean MacNamara identify several types of poliovirus, known as types 1, 2, and 3.
The United States of America establishes the National Foundation for Infantile Paralysis, which later becomes the March of Dimes – a fundraising organization focusing on polio research.
Thomas Weller and Frederick Robbins successfully grow poliovirus in live cells. Six years later they receive the Nobel Prize for their work.
Dr Jonas Salk develops the first vaccine against polio – an injectable, inactivated (killed) polio vaccine (IPV).
Dr Albert Sabin develops a "live" oral vaccine against polio (OPV), which rapidly becomes the vaccine of choice for most national immunization programmes in the world.
The World Health Assembly passes a resolution to create the Expanded Programme on Immunization (EPI) to bring vaccines to the world's children
Lameness surveys demonstrate that polio is widespread in many developing countries, leading to the introduction of routine immunization with OPV in almost all national immunization programmes.
Rotary International launches PolioPlus, the first and largest internationally coordinated private-sector support of a public health initiative, with an initial pledge of US$120 million.
The World Health Assembly passes a resolution to eradicate polio by the year 2000.
The Global Polio Eradication Initiative is launched.
The Global Polio Laboratory Network is formally established to detect the presence of wild and vaccine-derived polioviruses in countries.
The last case of wild polio occurs in the WHO Region of the Americas. He is a three-year old boy called Luis Fermin Tenorio living in Junin, Northern Peru.
The WHO Region of the Americas is certified polio-free.
In China, 80 million children are vaccinated.
More than 56 million children are vaccinated in 19 countries of the WHO European and Eastern Mediterranean Regions.
In India, 87 million children are vaccinated.
Nelson Mandela officially launches the Kick Polio Out of Africa campaign, and 420 million African children are vaccinated during National Immunization Days.
The last case of wild polio occurs in the WHO Western Pacific Region. She is a 15-month-old girl called Mum Chanty living near Phnom Penh, Cambodia.
In Turkey on 26 November, 1998, Melik Minas, a 33-month-old unvaccinated child, is the last child paralysed by indigenous wild poliovirus in the European Region.
The UN Secretary-General agrees to negotiate truces for immunization in the Democratic Republic of Congo.
National Immunization Days are conducted in war-torn Liberia.
The WHO Western Pacific Region is certified polio-free.
A record 550 million children – almost one-tenth of the world's population – receive the oral polio vaccine (OPV).
575 million children are vaccinated in 94 countries, including 35 million in Afghanistan and Pakistan, and 16 million in conflict-affected countries in central Africa.
The WHO European Region is certified polio-free.
500 million children are vaccinated in 100 countries.
In northern Nigeria, polio immunization campaigns are suspended following unfounded rumours regarding the safety of the polio vaccine. Subsequently, a new outbreak occurs.
In Africa, synchronized National Immunization Days in 23 countries target 80 million children – the largest coordinated polio immunization effort on the continent.
New monovalent oral polio vaccines (mOPV) become available to enhance the impact of supplementary immunization activities.
Four endemic countries remain: Afghanistan, India, Nigeria and Pakistan
Outbreaks in Yemen and Indonesia – which suffer the largest, single-country outbreaks in recent years – are successfully stopped.
More than 400 million children are immunized in 27 countries.
On International Peace Day, 80 000 previously inaccessible children are reached with polio vaccine in southern Afghanistan.
A new outbreak of polio spreads from Nigeria to West Africa.
Polio eradication becomes the World Health Organization’s "top operational priority".
The new bivalent oral poliovirus vaccine is used for the first time in Afghanistan.
The Global Polio Eradication Initiative © Copyright 2010