Severity of post polio syndrome symptoms depend upon the severity of initial infection. The more severe initial infection was the more severe post polio syndrome symptoms will be. Symptoms include muscle weakness, generalized and muscular fatigue, muscle atrophy, pain, sleep apnea and joint degeneration. Increased skeletal deformities such as scoliosis are also common. Aspiration pneumonia due to weakness in swallowing muscles and respiratory muscle weakness are usually fatal symptoms.