What percentage of polio survivors are estimated to develop Post-Polio Syndrome?

• A. About 90%
• B. About 10%
• C. Approximately half of all polio survivors.
• D. About 25%

Answer: (C)

Post-Polio Syndrome is the appearance of new or worsening weakness, fatigue, and pain many years after the original polio illness. The proportion of polio survivors who develop PPS is substantial but not universal, with most studies placing it around half of those who had polio. In other words, roughly 50% of survivors may experience PPS, though estimates can vary from a quarter to about half depending on how PPS is defined and the length of time since the initial infection. PPS typically emerges decades after recovery and is thought to result from the long-term effects of motor neuron loss from the initial polio infection, rather than a reactivation of the virus.