Post-Polio Syndrome


What Is It?

Post-polio syndrome is a set of symptoms, including muscle weakness and fatigue, that occur 15 to 30 years after recovery from polio (paralytic poliomyelitis). Symptoms generally involve the same muscle groups affected by earlier disease, but may extend to other muscle groups that were not involved initially. The syndrome is more frequent among older people and those who were more severely affected with polio.

Polio is an infection with the poliovirus that affects the motor system. However, post-polio syndrome is caused by poliovirus that remains in the body or is reactivated. Polio that affects the spinal cord usually destroys about half of the motor neurons that normally control the muscles of the body. The surviving neurons compensate for this loss by adopting orphaned muscle fibers. Post-polio syndrome occurs when these remaining motor neurons become disabled through illness, injury, bed rest, weight gain or aging.

People usually are affected during middle or late adult life after a long period of stability following polio. The new symptoms sometimes emerge after an illness or injury.


Major symptoms include muscle pain, weakness, fatigue and, in some cases, wasting (atrophy) of the muscles that were involved during the polio infection, typically the legs. Additional problems can include intolerance to heat or cold, and difficulty swallowing, breathing or sleeping. The syndrome also can cause abnormal muscle contractions, such as quivering or spasms, in small segments of a muscle. Worsening disability may cause social and psychological problems. Numbness or tingling can occur, but these sensory problems are uncommon.


Your doctor will ask about your medical history, especially your history of polio. A neurological exam can identify muscle weakness and atrophy. A test called an electromyelogram can help to diagnose this disease. In this procedure, small needles are inserted into several areas of muscle. Mild electric currents are used to stimulate muscle contraction so that their strength and function can be estimated even when nerves are not able to signal the muscles to work. When the diagnosis is uncertain, an electromyelogram can help to sort out whether weakness is caused by a muscle disease or by inadequate nerve signals.

Expected Duration

Post-polio syndrome is progressive, meaning it worsens over time. The progression occurs slowly, then usually stops after a period of one to 10 years.


In people who have a history of polio, there is no way to prevent post-polio syndrome. Vaccination against polio is recommended for children and for unvaccinated adults who are traveling to underdeveloped countries.


There is no specific treatment for post-polio syndrome. Physical therapy may be used to increase muscle strength and endurance, and to introduce lifestyle modifications including adjusting your pace of exercise to avoid rapid fatigue. Bracing, orthotics and other aids may support or substitute for affected muscles.

Complications that involve swallowing, or breathing disturbances (such as sleep apnea) require specific treatments. Examples might include using different positions during meals, or an air-pressure mask and machine that can be used during sleep to support breathing. Counseling with a psychologist, occupational therapist or vocational counselor should be considered for specific psychological or occupational adjustments. Support groups offer education, support and social opportunities.

When To Call A Professional

Call a medical professional if you notice changes in muscle strength, decreased endurance, muscle wasting or abnormal muscle twitching. Difficulties swallowing, breathing or sleeping also require medical attention.


The prognosis is good. Post-polio syndrome usually progresses slowly and stops progressing after one to 10 years. With a combination of physical therapy and lifestyle modifications, people can return to or approach their previous level of functioning.

Johns Hopkins patient information

Last revised:

Diseases and Conditions Center

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All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.