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.
MILESTONE: The first significant outbreak of infantile paralysis – subsequently identified as polio – is documented in the United States of America.
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 know as types 1, 2 and 3
MILESTONE: Thomas Weller and Frederick Robbins successfully grow poliovirus in live cells. Six years later they receive the Nobel Prize for their work.
MILESTONE: Dr Jonas Salk develops the first vaccine against polio – an injectable, inactivated (killed) polio vaccine (IPV).
MILESTONE: 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.
MILESTONE: The World Health Assembly passes a resolution to eradicate polio by the year 2000. The Global Polio Eradication Initiative is launched
The WHO Western Pacific Region is certified polio-free. A record of 550 million children - almost one-tenth of the worlds population - receive oral polio vaccine (OPV)
In northern Nigeria, polio immunisation campaigns are suspended following unfounded rumours regarding the safety of the vaccine. Subsequently, a new outbreak occurs.
New monovalent oral polio vaccines (mOPV) become available to enhance the impact of supplementary immunisation activities.
A new outbreak of polio spreads from Nigeria to West Africa. Becomes WHO's "top operational priority".
Nigeria, Pakistan, Afghanistan remain to be the only countries where polio is endemic
On March 27, 2014 the WHO announced the eradication of poliomyelitis in the South-East Asia Region, in which the WHO includes eleven countries: Bangladesh, Bhutan, North Korea, India, Indonesia, Maldives, Myanmar, Nepal, Sri Lanka, Thailand and Timor-Leste. With the addition of this region, the proportion of world population living in polio-free regions has reached 80%. The last case of wild polio in the South-East Asia Region was reported in India on 13 January 2011.