Old data show<unk>  occurs in roughly 25 to 50% of people who survive a<unk>  infection. However newer data from countries that have contacted their<unk>  survivors have shown 85% of their<unk>  survivors to have symptoms of<unk> . Typically, it occurs 30–35 years afterwards, but delays between 8 and 71 years have been recorded. The disease occurs sooner in persons with more severe initial infections. Other factors that increase the risk of<unk>  include increasing length of time since acute<unk> virus infection, presence of permanent residual impairment after recovery from the acute illness, and being female.PPS is documented to occur in cases of nonparalytic<unk>  (NPP). One review states late-onset weakness and fatigue occur in 14–42% of NPP patients.
Post-polio syndrome
Leukomyelitis
Guillain–Barré syndrome
FACES syndrome
Acute disseminated encephalomyelitis
Eastern equine encephalitis
Tension myositis syndrome
Postvaccinal encephalitis