Polio is an infectious viral disease that in its most severe form can infect the brain and spinal cord, leading to paralysis and sometimes death. Most people infected with polio will not get sick or have any visible symptoms. For those who do show symptoms, it includes fever, sore throat, tiredness, and nausea. A smaller proportion of people develop serious symptoms such as paresthesia and paralysis.
It is highly contagious, and best treated through prevention using the very effective vaccines available. Children typically receives four doses of the vaccine from ages 2 months - 6 years. Adults can also receive the vaccine through three doses.