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What is post-polio syndrome?

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Polio vaccine — polio A health care worker giving a polio vaccine to a child in Katsina state, Nigeria, 2014.

Post-polio syndrome (PPS) is a condition that can affect individuals years or even decades after their initial recovery from polio. It is characterized by the gradual return or onset of symptoms, including muscle weakness, fatigue, and joint or muscle pain. These symptoms may manifest in muscle groups that were originally affected by the disease or in previously unaffected limbs.123

The syndrome is not contagious and does not involve a reactivation of the poliovirus. While the exact cause remains uncertain, it is believed to arise from the long-term strain placed on nerve cells that survived the original infection. As patients reach middle age, these surviving nerve fibers may begin to deteriorate, leading to the observed decline in function.23

Although the condition can significantly impact mobility and quality of life, there is currently no cure for post-polio syndrome.32