See also the WHO page on the Polio eradication initiative.
Polio is a contagious disease affecting the nervous system. It primarily affects children under five years of age. About one per cent of all infections lead to paralysis of limbs. The virus survives only for a short time outside the human body. It is spread through respiratory droplets and through faecal matter. The symptoms are high fever and pain in the limbs, followed by acute flaccid paralysis. Immunisation by oral Polio vaccine is widespread.