Polio is a viral illness that, in about 95% of cases, actually produces no symptoms at all (called asymptomatic polio). In the 4% to 8% of cases in which there are symptoms (called symptomatic polio), the illness appears in three forms :
- a mild form called abortive polio (most people with this form of polio may not even suspect they have it because their sickness is limited to mild flu like symptoms such as mild upper respiratory infection, diarrhea, fever, sore throat, and a general feeling of being ill)
- a more serious form associated with aseptic meningitis called non paralytic polio (1% to 5% show neurological symptoms such as sensitivity to light and neck stiffness)
- a severe, debilitating form called paralytic polio (this occurs in 0.1% to 2% of cases)
People who have abortive polio or non paralytic polio usually make a full recovery. However, paralytic polio, as its name implies, causes muscle paralysis and can even result in death. In paralytic polio, the virus leaves the intestinal tract and enters the bloodstream, attacking the nerves (in abortive or asymptomatic polio, the virus usually doesn't get past the intestinal tract). The virus may affect the nerves governing the muscles in the limbs and the muscles necessary for breathing, causing respiratory difficulty and paralysis of the arms and legs.
By Steven Dowshen, MD
The above information thankfully comes from the Steven Dowshen, MD at the following link.