Causes, symptoms and treatment

The infection is caused by the consumption of infected foods. The virus thus enters the mouth and pharynx and spreads from here to the intestinal tract, where it multiplies and is ultimately excreted with the stools.
The incubation period (time from infection to the onset of the disease) is about six to ten days. If the infection stops at this stage, this is known as asymptomatic or abortive polio. This is the case in about 4 to 8 per cent of those infected.

The early stage of the disease manifests itself in mild, non-specific symptoms that may also occur with other virus infections: malaise, headaches, fever and possibly diarrhoea. With about 1 per cent of all polio infections, the virus breaches the barrier of the intestinal tract and infects the spinal cord and brain via the bloodstream. This also leads to a non-paralytic form of polio that is manifested by headaches as well as neck and back pain. Only in about 0.1 per cent of all infections does the virus attack the nerve cells of the spinal cord and/or brain directly. This is the paralytic form because paralysis occurs in this case.
Symptoms of long-term consequences of polio/post-polio syndrome are:

• A general lack of strength and endurance

• Extreme fatigue

• Difficulty breathing and swallowing

• Intolerance to cold temperatures

• Pain in the muscles and/or joints

• Increased muscle weakness/muscle pain

• Muscle atrophy (amyotrophia)

• Progressively unstable joints/joint deformities

• Cramps

• Muscle convulsions (fasciculations)

• Changes in the gait pattern and/or increased tendency to fall

Since no specific antiviral therapy is available, treatment is limited to symptomatic measures. These include bed rest with careful nursing, correct positioning and physical therapy. Aftercare includes appropriate physiotherapy and treatment with orthopaedic devices such as orthoses. This can improve mobility after the acute stage of the disease.