What is "poliomyelitis"

Infantile paralysis \In"fan*tile pa*ral"y*sis\ (Med.) An acute viral disease, affecting almost exclusively infants and young adults, characterized by inflammation of the anterior horns of the gray substance of the spinal cord. It is attended with febrile symptoms, motor paralysis, and muscular atrophy, often producing permanent deformities. Called also acute anterior poliomyelitis, poliomyelitis and polio. It is caused by any one of three polioviruses, and by the end of the twentieth century had been almost completely eradicated in developed countries by a widespread campaign of immunization.

1874, also polio-myelitis, coined by German physician Adolph Kussmaul (1822-1902) from Greek polios "grey" (see fallow (adj.)) + myelos "marrow" + -itis "inflammation." So called because the gray matter in the spinal cord is inflamed, which causes paralysis. The earlier name was infantile paralysis (1843).\n\nIn many respects, also, this affection resembles the acute spinal paralysis of infancy, which, from the researches of Charcot, Joffroy, and others, have been shown pathologically to be an acute myelitis of the anterior cornua. Hence, for these forms of paralysis, Professor Kussmaul suggests the name of 'poliomyelitis anterior.'

["London Medical Record," Dec. 9, 1874]

n. (context pathology English) Acute infection by the poliovirus, especially of the motor neurons in the spinal cord and brainstem, leading to muscle weakness, paralysis and sometimes deformity.

n. an acute viral disease marked by inflammation of nerve cells of the brain stem and spinal cord [syn: polio, infantile paralysis, acute anterior poliomyelitis]

Poliomyelitis, often called polio or infantile paralysis, is an infectious disease caused by the poliovirus. In about 0.5% of cases there is muscle weakness resulting in an inability to move. This can occur over a few hours to few days. The weakness most often involves the legs but may less commonly involve the muscles of the head, neck and diaphragm. Many but not all people fully recover. In those with muscle weakness about 2% to 5% of children and 15% to 30% of adults die. Another 25% of people have minor symptoms such as fever and a sore throat and up to 5% have headache, neck stiffness and pains in the arms and legs. These people are usually back to normal within one or two weeks. In up to 70% of infections there are no symptoms. Years after recovery post-polio syndrome may occur, with a slow development of muscle weakness similar to that which the person had during the initial infection.

Poliovirus is usually spread from person to person through infected fecal matter entering the mouth. It may also be spread by food or water containing human feces and less commonly from infected saliva. Those who are infected may spread the disease for up to six weeks even if no symptoms are present. The disease may be diagnosed by finding the virus in the feces or detecting antibodies against it in the blood. The disease only occurs naturally in humans.

The disease is preventable with the polio vaccine; however, a number of doses are required for it to be effective. The US Centers for Disease Control and Prevention recommends polio vaccination boosters for travelers and those who live in countries where the disease is occurring. Once infected there is no specific treatment. In 2015 polio affected less than 100 people, down from 350,000 cases in 1988. In 2014 the disease was only spreading between people in Afghanistan, Nigeria, and Pakistan. In 2015 Nigeria had stopped the spread of wild poliovirus but it reoccured in 2016.

Poliomyelitis has existed for thousands of years, with depictions of the disease in ancient art. The disease was first recognized as a distinct condition by Michael Underwood in 1789 and the virus that causes it was first identified in 1908 by Karl Landsteiner. Major outbreaks started to occur in the late 19th century in Europe and the United States. In the 20th century it became one of the most worrying childhood diseases in these areas. The first polio vaccine was developed in the 1950s by Jonas Salk. It is hoped that vaccination efforts and early detection of cases will result in global eradication of the disease by 2018.