- Creutzfeldt-Jakob Disease
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Polio is a highly infectious disease caused by a virus that affects the nervous system. The virus spreads by direct person-to-person contact, contact with infected mucus or phlegm from the nose or mouth, or contact with infected feces.
Between 1840 and the 1950s, polio was a worldwide epidemic. Since the development of polio vaccines, the incidence of the disease has been greatly reduced. Polio has been wiped out in a number of countries. There have been very few cases of polio in the Western Hemisphere since the late 1970s. Children in the United States are now routinely vaccinated against the disease.
Approximately 95 percent of persons infected with polio will have no symptoms. About 4 to 8 percent of infected persons have minor symptoms, such as fever, fatigue, nausea, headache, flu-like symptoms, stiffness in the neck and back, and pain in the limbs, which often resolve completely. Fewer than 1 percent of polio cases result in permanent paralysis of the limbs (usually the legs). Of those paralyzed, 5 to 10 percent die when the paralysis strikes the respiratory muscles.
For polio infections, the goal of treatment is to control symptoms while the infection runs its course. Antibiotics may be given for urinary tract infections. Moist heat may be applied to reduce muscle pain and spasms. Painkillers may be administered to reduce headache, muscle pain, and spasms. Sometimes individuals may undergo physical therapy or wear corrective braces or shoes to help recover muscle strength and function.
The best way to prevent polio is through vaccination. Thanks to a massive, global vaccination campaign during the past 20 years, polio exists in only a few countries in Africa and Asia. Although rare in the Western world, polio outbreaks still occasionally occur, usually in groups of people who have not been vaccinated. Polio often occurs after someone travels to a region where the disease is common.