When can post-polio syndrome develop after an earlier polio infection?

Post-polio syndrome is a condition that can develop in former polio patients long after their initial recovery from the disease. The development of this syndrome appears to be time-related, typically occurring between 25 and 40 years after the initial infection. It may also be described as manifesting years or even decades after the patient has stabilized following the original illness.123

The syndrome is characterized by the onset of new symptoms, including muscle weakness, fatigue, and joint or muscle pain, which may affect limbs that were originally impacted by the virus or previously unaffected muscle groups. While the exact cause is not definitively known, it is believed to result from the long-term strain on nerve cells that survived the initial infection, leading to their gradual deterioration as the individual ages. It is important to note that post-polio syndrome does not involve a reactivation of the poliovirus and is not contagious.123