Poliomyelitis (polio) is a highly contagious disease, but in the majority of cases it causes no symptoms. Since the implementation of polio vaccines the number of cases has greatly reduced, and many countries are now thought to have eliminated the poliovirus. Infection is possible in the endemic regions of Asia and Africa if immunisation coverage is suboptimal. Rapidly developing flaccid paralysis is asymmetrical. Sensation is preserved in the paralysed limbs. Post-polio syndrome (e.g. fatigue, muscle weakness, myalgia and arthralgia) is a condition that affects patients several years after recovery from an initial acute attack. The treatment of these late effects is symptomatic (analgesia, exercises, rest, weight control, assistive devices).