what is polio?
It is an infectious disease caused by the poliovirus.
Polio
Poliomyelitis, commonly shortened to polio, is an infectious disease caused by the poliovirus. 
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Polio [SEP] Introduction
Poliomyelitis, commonly shortened to polio, is an infectious disease caused by the poliovirus. In about 0.5 percent of cases, it moves from the gut to affect the central nervous system and there is muscle weakness resulting in a flaccid paralysis. This can occur over a few hours to a few days. The weakness most often involves the legs, but may less commonly involve the muscles of the head, neck and diaphragm. Many people fully recover. In those with muscle weakness, about 2 to 5 percent of children and 15 to 30 percent of adults die. For all those infected, in up to 70 percent of infections there are no symptoms.