Polio is an infectious disease caused by a virus. The virus lives in an infected person's throat and intestines. It is most often spread by contact with the stool of an infected person. You can also get it from droplets if an infected person sneezes or coughs. It can contaminate food and water if people do not wash their hands.

Most people have no symptoms. If you have symptoms, they may include fever, fatigue, nausea, headache, flu-like symptoms, stiff neck and back, and pain in the limbs. A few people will become paralyzed. There is no treatment to reverse the paralysis of polio.

Some people who've had polio develop post-polio syndrome (PPS) years later. Symptoms include tiredness, new muscle weakness, and muscle and joint pain. There is no way to prevent or cure PPS.

The polio vaccine has wiped out polio in the United States and most other countries.

Centers for Disease Control and Prevention